idnits 2.17.1 draft-ietf-sigtran-sua-16.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- ** Looks like you're using RFC 2026 boilerplate. This must be updated to follow RFC 3978/3979, as updated by RFC 4748. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- ** The document seems to lack a 1id_guidelines paragraph about 6 months document validity -- however, there's a paragraph with a matching beginning. Boilerplate error? == No 'Intended status' indicated for this document; assuming Proposed Standard Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- == There are 2 instances of lines with non-RFC6890-compliant IPv4 addresses in the document. If these are example addresses, they should be changed. ** The document seems to lack a both a reference to RFC 2119 and the recommended RFC 2119 boilerplate, even if it appears to use RFC 2119 keywords. RFC 2119 keyword, line 203: '...procedures. Routing keys MUST NOT span...' RFC 2119 keyword, line 221: '...ired endpoint. The AMF MAY use routing...' RFC 2119 keyword, line 529: '...efault treatment MAY be specified. Po...' RFC 2119 keyword, line 537: '...he SS7 network, the ASP MAY perform an...' RFC 2119 keyword, line 588: '...agement messages. It is OPTIONAL that...' (156 more instances...) Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the RFC 3978 Section 5.4 Copyright Line does not match the current year == Line 4686 has weird spacing: '...essages until...' == Using lowercase 'not' together with uppercase 'MUST', 'SHALL', 'SHOULD', or 'RECOMMENDED' is not an accepted usage according to RFC 2119. Please use uppercase 'NOT' together with RFC 2119 keywords (if that is what you mean). Found 'MUST not' in this paragraph: The SCTP Payload Protocol Identifier value "4" SHOULD be included in each SCTP DATA chunk, to indicate that the SCTP is carrying the SUA protocol. The value "0" (unspecified) is also allowed but any other values MUST not be used. This Payload Protocol Identifier is not directly used by SCTP but MAY be used by certain network entities to identify the type of information being carried in a DATA chunk. -- The document seems to lack a disclaimer for pre-RFC5378 work, but may have content which was first submitted before 10 November 2008. If you have contacted all the original authors and they are all willing to grant the BCP78 rights to the IETF Trust, then this is fine, and you can ignore this comment. If not, you may need to add the pre-RFC5378 disclaimer. (See the Legal Provisions document at https://trustee.ietf.org/license-info for more information.) -- Couldn't find a document date in the document -- date freshness check skipped. Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Missing Reference: '2719' is mentioned on line 5493, but not defined == Missing Reference: 'ANSI TCAP' is mentioned on line 5502, but not defined == Missing Reference: 'ITU TCAP' is mentioned on line 5508, but not defined == Missing Reference: 'RANAP' is mentioned on line 5514, but not defined == Missing Reference: 'ITU-T Q.714' is mentioned on line 484, but not defined == Missing Reference: '2916' is mentioned on line 5496, but not defined == Missing Reference: 'SCTP' is mentioned on line 691, but not defined == Missing Reference: 'RFC2119' is mentioned on line 881, but not defined == Missing Reference: 'ASPAC-Ack' is mentioned on line 4187, but not defined == Missing Reference: 'ASPIA-Ack' is mentioned on line 4187, but not defined == Missing Reference: 'ASPUP-Ack' is mentioned on line 4197, but not defined == Missing Reference: 'RFC2434' is mentioned on line 5345, but not defined ** Obsolete undefined reference: RFC 2434 (Obsoleted by RFC 5226) == Missing Reference: '2434' is mentioned on line 5489, but not defined == Missing Reference: 'ANSI-MTP' is mentioned on line 5499, but not defined == Missing Reference: 'ITU-MTP' is mentioned on line 5505, but not defined == Missing Reference: 'M3UA' is mentioned on line 5511, but not defined == Missing Reference: 'UTRAN IUR' is mentioned on line 5519, but not defined ** Obsolete normative reference: RFC 2279 (Obsoleted by RFC 3629) ** Obsolete normative reference: RFC 2960 (Obsoleted by RFC 4960) -- Possible downref: Non-RFC (?) normative reference: ref. 'ANSI SCCP' -- Possible downref: Non-RFC (?) normative reference: ref. 'ITU SCCP' -- Possible downref: Non-RFC (?) normative reference: ref. 'SIGSEC' Summary: 6 errors (**), 0 flaws (~~), 22 warnings (==), 5 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 1 INTERNET-DRAFT J. Loughney (Editor) 2 Internet Engineering Task Force Nokia 3 G. Sidebottom 4 gregside Consulting 5 Issued: December 11, 2003 L. Coene, G. Verwimp 6 Expires: June 10, 2003 Siemens 7 J. Keller 8 Tekelec 9 B. Bidulock 10 OpenSS7 Corporation 12 Signalling Connection Control Part User Adaptation Layer (SUA) 13 15 Status of This Memo 17 This document is an Internet-Draft and is in full conformance with 18 all provisions of Section 10 of RFC 2026. 20 Internet-Drafts are working documents of the Internet Engineering 21 Task Force (IETF), its areas, and its working groups. Note that 22 other groups may also distribute working documents as Internet- 23 Drafts. 25 Internet-Drafts are draft documents valid for a maximum of six 26 months and may be updated, replaced, or obsoleted by other documents 27 at any time. It is inappropriate to use Internet-Drafts as 28 reference material or to cite them other than as 'work in progress.' 30 The list of current Internet-Drafts can be accessed at 31 http://www.ietf.org/ietf/1id-abstracts.txt 33 The list of Internet-Draft Shadow Directories can be accessed at 34 http://www.ietf.org/shadow.html. 36 This draft expires on April 5, 2003. 38 Abstract 40 This Internet Draft defines a protocol for the transport of any 41 Signalling Connection Control Part-User signalling over IP using the 42 Stream Control Transmission 43 Protocol. The protocol is designed to be modular and symmetric, to 44 allow it to work in diverse architectures, such as a Signalling 45 Gateway to IP Signalling Endpoint architecture as well as a peer-to- 46 peer IP Signalling Endpoint architecture. 48 Abstract..............................................................1 49 1. Introduction.......................................................3 50 1.1 Scope.............................................................3 51 1.2 Terminology and Abbreviations.....................................3 52 1.3 Signalling Transport Architecture.................................6 53 1.4 Services Provided by the SUA Layer................................8 54 1.5 Internal Functions Provided in the SUA Layer.....................10 55 1.6 Definition of SUA Boundaries.....................................13 56 2 Conventions........................................................18 57 3 Protocol Elements..................................................18 58 3.1 Common Message Header............................................18 59 3.2 SUA Connectionless Messages......................................22 60 3.3 Connection Oriented Messages.....................................26 61 3.4 Signalling Network Management (SNM) Messages.....................37 62 3.5 Application Server Process State Maintenance Messages............43 63 3.6 ASP Traffic Maintenance Messages.................................46 64 3.7 SUA Management Messages..........................................49 65 3.8 Routing Key Management (RKM) Messages............................51 66 3.9 Common Parameters................................................54 67 3.10 SUA-Specific parameters.........................................66 68 4. Procedures........................................................82 69 4.1 Procedures to Support the SUA-User Layer.........................82 70 4.2 Receipt of Primitives from the Layer Management..................83 71 4.3 AS and ASP State Maintenance.....................................85 72 4.4 Routing Key Management Procedures................................98 73 4.5 Availability and/or Congestion Status of SS7 Destination Support101 74 4.6 MTP3 Restart....................................................103 75 4.7 SCCP - SUA Interworking at the SG...............................104 76 4.8 NIF Not Available on SGP...............Error! Bookmark not defined. 77 5 Examples of SUA Procedures........................................106 78 5.1 SG Architecture.................................................106 79 5.2 IPSP Examples...................................................107 80 6 Security Considerations...........................................109 81 7 IANA Considerations...............................................110 82 7.1 SCTP Payload Protocol ID........................................110 83 7.2 Port Number.....................................................110 84 7.3 Protocol Extensions.............................................110 85 8 Timer Values......................................................111 86 9 Acknowledgements..................................................111 87 10 Authors' Addresses...............................................112 88 11 References.......................................................113 89 11.1 Normative......................................................113 90 11.2 Non-Normative..................................................113 91 Appendix A Signalling Network Architecture..........................114 92 A.1 Generalized Peer-to-Peer Network Architecture...................114 93 A.2 Signalling Gateway Network Architecture.........................115 94 A.3 Signalling Gateway Message Distribution Recommendations.........116 95 1. Introduction 97 There is on-going integration of switched circuit networks and IP 98 networks. Network service providers are designing IP-based 99 signalling architectures that need support for SS7 and SS7-like 100 signalling protocols. IP provides an effective way to transport user 101 data and for operators to expand their networks and build new 102 services. In these networks, there is need for interworking between 103 the SS7 and IP domains [2719]. 105 This draft defines a protocol for the transport SS7 SCCP user- 106 protocols [ANSI SCCP] [ITU SCCP], such as TCAP and RANAP, over IP 107 using the Stream Control Transmission Protocol (SCTP) [2960]. 109 1.1 Scope 111 This document details the delivery of SCCP-user messages (MAP & CAP 112 over TCAP [ANSI TCAP] [ITU TCAP], RANAP [RANAP], etc.) messages over 113 IP between two signalling endpoints. Consideration is given for the 114 transport from a signalling gateway to an IP signalling node (such 115 as an IP-resident Database) as described in the Framework 116 Architecture for Signalling Transport [2719]. This protocol can also 117 support transport of SCCP-user messages between two endpoints wholly 118 contained within an IP network. 120 The delivery mechanism addresses the following criteria: 122 * Support for transfer of SCCP-User Part messages 123 * Support for SCCP connectionless service. 124 * Support for SCCP connection oriented service. 125 * Support for the operation of SCCP-User protocol peers. 126 * Support for the management of SCTP transport associations 127 between signalling gateways and IP-based signalling nodes. 128 * Support for distributed IP-based signalling nodes. 129 * Support for the asynchronous reporting of status changes to 130 management functions. 132 1.2 Terminology and Abbreviations 134 1.2.1 Appreviations 136 CAP - CAMEL Application Protocol. 138 GTT - Global Title Translation. 140 MAP - Mobile Application Protocol. 142 PC - Signalling System no. 7 Point Code. 144 RANAP - Radio Access Network Application Protocol. 146 SCTP - Stream Control Transmission Protocol. 148 SS7 - Signalling System no. 7. 150 TCAP - Transaction Capabilities Application Protocol. 152 1.2.2 Terminology 154 Signalling Gateway (SG) - Network element that terminates switched 155 circuit networks and transports SCCP-User signalling over IP to an 156 IP signalling endpoint. A Signalling Gateway could be modeled as 157 one or more Signalling Gateway Processes, which are located at the 158 border of the SS7 and IP networks. Where an SG contains more than 159 one SGP, the SG is a logical entity and the contained SGPs are 160 assumed to be coordinated into a single management view to the SS7 161 network and to the supported Application Servers. 163 Application Server (AS) - A logical entity serving a specific 164 Routing Key. An example of an Application Server is a virtual IP 165 database element handling all requests for an SCCP-user. The AS 166 contains a set of one or more unique Application Server Processes, 167 of which one or more is normally actively processing traffic. 169 Application Server Process (ASP) - An Application Server Process 170 serves as an active or backup process of an Application Server 171 (e.g., part of a distributed signalling node or database element). 172 Examples of ASPs are MGCs, IP SCPs, or IP-based HLRs. An ASP 173 contains an SCTP end-point and may be configured to process traffic 174 within more than one Application Server. 176 IP Server Process (IPSP) - A process instance of an IP-based 177 application. An IPSP is essentially the same as an ASP, except that 178 it uses SUA in a peer-to-peer fashion. Conceptually, an IPSP does 179 not use the services of a Signalling Gateway. 181 Signalling Gateway Process (SGP) - A process instance of a 182 Signalling Gateway. It serves as an active, load-sharing or 183 broadcast process of a Signalling Gateway. 185 Signalling Process - A process instance that uses SUA to communicate 186 with other signalling process. An ASP, a SGP and an IPSP are all 187 signalling processes. 189 Association - An association refers to an SCTP association. The 190 association provides the transport for the delivery of SCCP-User 191 protocol data units and SUA layer peer messages. 193 Routing Key - The Routing Key describes a set of SS7 parameters 194 and/or parameter-ranges that uniquely defines the range of 195 signalling traffic configured to be handled by a particular 196 Application Server. An example would be where a Routing Key consists 197 of a particular SS7 SCCP SSN plus an identifier to uniquely mark the 198 network that the SSN belongs to, for which all traffic would be 199 directed to a particular Application Server. Routing Keys are 200 mutually exclusive in the sense that a received SS7 signalling 201 message cannot be directed to more than one Routing Key. Routing 202 Keys can be provisioned, for example, by a MIB or registered using 203 SUA's dynamic registration procedures. Routing keys MUST NOT span 204 multiple network appearances. 206 Routing Context - An Application Server Process may be configured to 207 process traffic within more than one Application Server. In this 208 case, the Routing Context parameter is exchanged between the SGP and 209 the ASP (or between two ASPs), identifying the relevant Application 210 Server. From the perspective of an SGP/ASP, the Routing Context 211 uniquely identifies the range of traffic associated with a 212 particular Application Server, which the ASP is configured to 213 receive. There is a 1:1 relationship between a Routing Context value 214 and a Routing Key within an AS. Therefore the Routing Context can 215 be viewed as an index into an AS Table containing the AS Routing 216 Keys. 218 Address Mapping Function (AMF) - The AMF is an implementation 219 dependent function that is responsible for resolving the address 220 presented in the incoming SCCP/SUA message to correct SCTP 221 association for the desired endpoint. The AMF MAY use routing 222 context / rouging key information as selection criteria for the 223 appropriate SCTP association. 225 Fail-over - The capability to re-route signalling traffic as 226 required to an alternate Application Server Process, or group of 227 ASPs, within an Application Server in the event of failure or 228 unavailability of a currently used Application Server Process. 229 Fail-over may apply upon the return to service of a previously 230 unavailable Application Server Process. 232 Host - The computing platform that the SGP or ASP process is running 233 on. 235 Layer Management - Layer Management is a nodal function that handles 236 the inputs and outputs between the SUA layer and a local management 237 entity. 239 Network Appearance - The Network Appearance is an SUA local 240 reference (typically an integer) shared by SG and AS that together 241 with a Signalling Point Code uniquely identifies an SS7 node by 242 indicating the specific SS7 network it belongs to. 244 Network Byte Order - Most significant byte first, a.k.a. Big Endian. 246 Stream - A stream refers to an SCTP stream; a uni-directional 247 logical channel established from one SCTP endpoint to another 248 associated SCTP endpoint, within which all user messages are 249 delivered in-sequence except for those submitted to the un-ordered 250 delivery service. 252 Transport address - an address that serves as a source or 253 destination for the unreliable packet transport service used by 254 SCTP. In IP networks, a transport address is defined by the 255 combination of an IP address and an SCTP port number. Note, only 256 one SCTP port may be defined for each endpoint, but each SCTP 257 endpoint may have multiple IP addresses. 259 1.3 Signalling Transport Architecture 261 The framework architecture that has been defined for switched 262 circuit networks signalling transport over IP [2719] uses multiple 263 components, including an IP transport protocol, a signalling common 264 transport protocol and an adaptation module to support the services 265 expected by a particular switched circuit networks signalling 266 protocol from its underlying protocol layer. 268 In general terms, the SUA architecture can be modeled as a peer-to- 269 peer architecture. The first section considers the SS7 to IP 270 interworking architectures for connectionless and connection- 271 oriented transport. For this case, it is assumed that the ASP 272 initiates the establishment of the SCTP association with SG. 274 1.3.1 Protocol Architecture for Connectionless Transport 276 In this architecture, the SCCP and SUA layers interface in the SG. 277 Interworking between the SCCP and SUA layers is needed to provide 278 for the transfer of the user messages as well as the management 279 messages. 281 ******** SS7 *************** IP ******** 282 * SEP *---------* *--------* * 283 * or * * SG * * ASP * 284 * STP * * * * * 285 ******** *************** ******** 287 +------ +------+ 288 | SUAP | | SUAP | 289 +------+ +------+------+ +------+ 290 | SCCP | | SCCP | SUA | | SUA | 291 +------+ +------+------+ +------+ 292 | MTP3 | | MTP3 | | | | 293 +------+ +------+ SCTP | | SCTP | 294 | MTP2 | | MTP2 | | | | 295 +------+ +------+------+ +------+ 296 | L1 | | L1 | IP | | IP | 297 +------+ +------+------+ +------+ 298 | | | | 299 +---------------+ +------------+ 301 SUAP - SCCP/SUA User Protocol (TCAP, for example) 302 STP - SS7 Signalling Transfer Point 304 See Appendix A.3.1 for operation recommendations. 306 1.3.1.1 SG as endpoint 308 In this case, the connectionless SCCP messages are routed on point 309 code (PC) and subsystem number (SSN). The subsystem identified by 310 SSN and Routing Context is regarded as local to the SG. This means 311 from SS7 point of view, the SCCP-user is located at the SG. 313 1.3.1.2 Signalling Gateway as relay-point 315 A Global Title translation is executed at the signalling gateway, 316 before the destination of the message can be determined. The actual 317 location of the SCCP-user is irrelevant to the SS7 network. GT 318 Translation yields an "SCCP entity set", from which an Application 319 Server can be derived. Selection of the Application Server is based 320 on the SCCP called party address (and possibly other SS7 parameters 321 depending on the implementation). 323 1.3.2 Protocol Architecture for Connection-Oriented Transport 325 In this architecture, the SCCP and SUA layers share an interface in 326 the signalling gateway process to associate the two connection 327 sections needed for the connection-oriented data transfer between 328 SEP and ASP. Both connection sections are setup when routing the 329 Connect Request messages from the signalling end point via 330 signalling gateway process to ASP and visa-versa. The routing of 331 the Connect Request message is performed in the same way as 332 described in 1.3.1. 334 ******** SS7 *************** IP ******** 335 * SEP/ *---------* SG *--------* ASP * 336 * STP * * * * * 337 ******** *************** ******** 339 +------+ +------+ 340 | SUAP | | SUAP | 341 +------+ +------+------+ +------+ 342 | SCCP | | SCCP | SUA | | SUA | 343 +------+ +------+------+ +------+ 344 | MTP3 | | MTP3 | | | | 345 +------| +------+ SCTP | | SCTP | 346 | MTP2 | | MTP2 | | | | 347 +------+ +------+------+ +------+ 348 | L1 | | L1 | IP | | IP | 349 +------+ +------+------+ +------+ 350 | | | | 351 +---------------+ +------------+ 353 SUAP - SCCP/SUA Application Protocol (e.g. - RANAP/RNSAP) 354 STP - SS7 Signalling Transfer Point 356 See Appendix A.3.2 for operation recommendations. 358 1.3.3 All IP Architecture 360 This architecture can be used to carry a protocol that uses the 361 transport services of SCCP within an IP network. This allows 362 flexibility in developing networks, especially when interaction 363 between legacy signalling is not needed. The architecture removes 364 the need for signalling gateway functionality. 366 ******** IP ******** 367 * IPSP *--------* IPSP * 368 ******** ******** 370 +------+ +------+ 371 | SUAP | | SUAP | 372 +------+ +------+ 373 | SUA | | SUA | 374 +------+ +------+ 375 | SCTP | | SCTP | 376 +------+ +------+ 377 | IP | | IP | 378 +------+ +------+ 379 | | 380 +----------------+ 382 SUAP - SCCP/SUA Application Protocol (e.g. - RANAP/RNSAP) 384 1.3.4 ASP Fail-over Model and Terminology 386 The SUA protocol supports ASP fail-over functions to support a high 387 availability of transaction processing capability. 389 An Application Server can be considered as a list of all ASPs 390 configured/registered to handle SCCP-user messages within a certain 391 range of routing information, known as a Routing Key. One or more 392 ASPs in the list may normally be active to handle traffic, while 393 others may be inactive but available in the event of failure or 394 unavailability of the active ASP(s). 396 For operation recommendations, see Appendix A. 398 1.4 Services Provided by the SUA Layer 400 1.4.1 Support for the transport of SCCP-User Messages 402 The SUA supports the transfer of SCCP-user messages. The SUA layer 403 at the signalling gateway and at the ASP support the seamless 404 transport of user messages between the signalling gateway and the 405 ASP. 407 1.4.2 SCCP Protocol Class Support 409 Depending upon the SCCP-users supported, the SUA supports the 4 410 possible SCCP protocol classes transparently. The SCCP protocol 411 classes are defined as follows: 413 * Protocol class 0 provides unordered transfer of SCCP-user 414 messages in a connectionless manner. 416 * Protocol class 1 allows the SCCP-user to select the in- 417 sequence delivery of SCCP-user messages in a connectionless 418 manner. 420 * Protocol class 2 allows the bi-directional transfer of SCCP- 421 user messages by setting up a temporary or permanent 422 signalling connection. 424 * Protocol class 3 allows the features of protocol class 2 with 425 the inclusion of flow control. Detection of message loss or 426 mis-sequencing is included. 428 Protocol classes 0 and 1 make up the SCCP connectionless service. 429 Protocol classes 2 and 3 make up the SCCP connection-oriented 430 service. 432 1.4.3 Native Management Functions 434 The SUA layer provides the capability to indicate errors associated 435 with the SUA-protocol messages and to provide notification to local 436 management and the remote peer as is necessary. 438 1.4.4 Interworking with SCCP Network Management Functions 440 SUA uses the existing ASP management messages for ASP status 441 handling. The interworking with SCCP management messages consists 442 of DUNA, DAVA, DAUD, DRST, DUPU or SCON messages (defined in section 443 3) on receipt of SSP, SSA, SST or SSC (defined by SCCP) to the 444 appropriate ASPs. See also chapter 1.4.5. The primitives below are 445 sent between the SCCP and SUA management functions in the SG to 446 trigger events in the IP and SS7 domain. 448 Generic |Specific | 449 Name |Name |ANSI/ITU Reference 450 ----------+-----------+--------------------------------------------- 451 N-State |Request |ITU-Q.711 Chap 6.3.2.3.2 (Tab 16/Q.711) 452 |Indication |ANSI-T1.112 Chap 2.3.2.3.2 (Tab 8E/T1.112.1) 453 ----------+-----------+--------------------------------------------- 454 N-Pcstate |Indication |ITU-Q.711 Chap 6.3.2.3.3 (Tab 1/Q.711) 455 | |ANSI-T1.112 Chap 2.3.2.3.4 (Tab 8G/T1.112.1) 456 ----------+-----------+--------------------------------------------- 457 N-Coord |Request |ITU-Q.711 Chap 6.3.2.3.1 (Tab 15/Q.711) 458 |Indication |ANSI-T1.112 Chap 2.3.2.3.3 (Tab 8F/T1.112.1) 459 |Response | 460 |Confirm | 462 1.4.5 Support for the management between the SGP and ASP. 464 The SUA layer provides interworking with SCCP management functions 465 at the SG for interoperation between the switched circuit networks 466 and the IP network. It should: 468 * Provide an indication to the SCCP-user at an ASP that a SS7 469 endpoint/peer is unreachable. 470 * Provide an indication to the SCCP-user at an ASP that a SS7 471 endpoint/peer is reachable. 472 * Provide congestion indication to SCCP-user at an ASP. 473 * Provide the initiation of an audit of SS7 endpoints at the 474 SG. 476 1.4.6 Relay function 478 For network scalability purposes, the SUA may be enhanced with a 479 relay functionality to determine the next hop SCTP association 480 towards the destination SUA endpoint. 482 The determination of the next hop may be based on Global Title 483 information (e.g. E.164 number), in analogy with SCCP GTT in SS7 484 networks, modeled in [ITU-T Q.714]. It may also be based on Hostname 485 information, IP address or pointcode contained in the called party 486 address. 488 This allows for greater scalability, reliability and flexibility in 489 wide-scale deployments of SUA. The usage of a relay function is a 490 deployment decision. 492 1.5 Internal Functions Provided in the SUA Layer 494 To perform its addressing and relaying capabilities, the SUA makes 495 use of an Address Mapping Function (AMF). This function is 496 considered part of SUA, but the way it is realized is left 497 implementation / deployment dependent (local tables, DNS [2916], 498 LDAP, etc.) 499 The AMF is invoked when a message is received at the incoming 500 interface. The AMF is responsible for resolving the address 501 presented in the incoming SCCP/SUA message to SCTP associations to 502 destinations within the IP network. The AMF will select the 503 appropriate SCTP association based upon routing context / routing 504 key information available. The destination might be the end SUA node 505 or a SUA relay node. The Routing Keys reference an Application 506 Server, which will have one or more ASPs processing traffic for the 507 AS. The availability and status of the ASPs is handled by SUA ASP 508 management messages. 510 Possible SS7 address/routing information that comprise a Routing Key 511 entry includes, for example, OPC, DPC, SIO found in the MTP3 routing 512 label, SCCP subsystem number, or Transaction ID. IP addresses and 513 hostnames can also be used as Routing Key Information. 515 It is expected that the routing keys be provisioned via a MIB, 516 dynamic registration or external process, such as a database. 518 1.5.1 Address Mapping at the SG 520 Normally, one or more ASPs are active in the AS (i.e., currently 521 processing traffic) but in certain failure and transition cases it 522 is possible that there may not be an active ASP available. The SGP 523 will buffer the message destined for this AS for a time T(r) or 524 until an ASP becomes available. When no ASP becomes available before 525 expiry of T(r), the SGP will flush the buffered messages and 526 initiate the appropriate return or refusal procedures. 528 If there is no address mapping match for an incoming message, a 529 default treatment MAY be specified. Possible solutions are to 530 provide a default Application Server to direct all unallocated 531 traffic to a (set of) default ASP(s), or to drop the messages and 532 provide a notification to management. The treatment of unallocated 533 traffic is implementation dependent. 535 1.5.2 Address Mapping at the ASP 537 To direct messages to the SS7 network, the ASP MAY perform an 538 address mapping to choose the proper SGP for a given message. This 539 is accomplished by observing the Destination Point Code and other 540 elements of the outgoing message, SS7 network status, SGP 541 availability, and Routing Context configuration tables. 543 A Signalling Gateway may be composed of one or more SGPs. There is, 544 however, no SUA messaging to manage the status of an SGP. Whenever 545 an SCTP association to an SGP exists, it is assumed to be available. 546 Also, every SGP of one SG communicating with one ASP regarding one 547 AS provides identical SS7 connectivity to this ASP. 549 An ASP routes responses to the SGP that it received messages from; 550 within the routing context which it is currently active and 551 receiving traffic. 553 1.5.3 Address Mapping Function at a Relay Node 555 The relay function is invoked when: 557 - Routing is on Global Title 558 - Routing is on Hostname 559 - Routing is on SSN and PC or SSN and IP Address and the 560 address presented is not the one of the relay node 562 Translation/resolution of the above address information yields one 563 of the following: 565 - Route on SSN: SCTP association ID towards the destination 566 node, SSN and optionally Routing Context and/or IP address. 567 - Route on GT: SCTP association ID towards next relay node, 568 (new) GT and optionally SSN and/or Routing Context. 569 - Routing on Hostname: SCTP association ID towards next relay 570 node, (new) Hostname and optionally SSN and/or Routing 571 Context. 572 - A local SUA-user (combined relay/end node) 574 To prevent looping, an SS7 hop counter is used. The originating end 575 node (be it an SS7 or an IP node) sets the value of the SS7 hop 576 counter to the maximum value (15 or less). Each time the relay 577 function is invoked within an intermediate (relay) node, the SS7 hop 578 counter is decremented. When the value reaches zero, the return or 579 refusal procedures are invoked with reason "Hop counter violation". 581 1.5.4 SCTP Stream Mapping 583 The SUA supports SCTP streams. Signalling Gateway SG and Application 584 Servers need to maintain a list of SCTP and SUA-users for mapping 585 purposes. SCCP-users requiring sequenced message transfer need to 586 be sent over a stream with sequenced delivery. 588 SUA uses stream 0 for SUA management messages. It is OPTIONAL that 589 sequenced delivery be used to preserve the order of management 590 message delivery. 592 Stream selection based on protocol class: 594 - Protocol class 0: SUA MAY select unordered delivery. The 595 stream selected is based on traffic information available 596 to the SGP or ASP. 597 - Protocol class 1: SUA MUST select ordered delivery. The 598 stream selected is based upon the sequence parameter given by 599 the upper layer over the primitive interface and other 600 traffic information available to the SGP or ASP 602 - Protocol classes 2 and 3: SUA MUST select ordered delivery. 603 The stream selected is based upon the source local reference 604 of the connection and other traffic information available to 605 the SGP or ASP. 607 1.5.5 Flow Control 609 Local Management at an ASP may wish to stop traffic across an SCTP 610 association to temporarily remove the association from service or to 611 perform testing and maintenance activity. The function could 612 optionally be used to control the start of traffic on to a newly 613 available SCTP association. 615 1.5.6 Congestion Management 617 The SUA layer is informed of local and IP network congestion by 618 means of an implementation-dependent function (e.g., an 619 implementation-dependent indication from the SCTP of IP network 620 congestion). 622 At an ASP or IPSP, the SUA layer indicates congestion to local SCCP- 623 Users by means of an appropriate SCCP primitive (e.g. N-INFORM, N- 624 NOTICE), as per current SCCP procedures, to invoke appropriate upper 625 layer responses. When an SG determines that the transport of SS7 626 messages is encountering congestion, the SG MAY trigger SS7 SCCP 627 Congestion messages to originating SS7 nodes, per the congestion 628 procedures of the relevant SCCP standard. The triggering of SS7 SCCP 629 Management messages from an SG is an implementation-dependent 630 function. 632 The SUA layer at an ASP or IPSP MAY indicate local congestion to an 633 SUA peer with an SCON message. When an SG receives a congestion 634 message (SCON) from an ASP, and the SG determines that an endpoint 635 is now encountering congestion, it MAY trigger congestion procedures 636 of the relevant SCCP standard. 638 1.6 Definition of SUA Boundaries 640 1.6.1 Definition of the upper boundary 642 The following primitives are supported between the SUA and an SCCP- 643 user (a reference to ITU and ANSI sections where these primitives 644 and corresponding parameters are described, is also given): 646 Generic |Specific | 647 Name |Name |ANSI/ITU Reference 648 ------------+----------+------------------------------------------- 649 N-CONNECT |Request |ITU-Q.711 Chap 6.1.1.2.2 (Tab 2/Q.711) 650 |Indication|ANSI-T1.112 Chap 2.1.1.2.2 (Tab 2/T1.112.1) 651 |Response | 652 |Confirm | 653 ------------+----------+------------------------------------------- 654 N-DATA |Request |ITU-Q.711 Chap 6.1.1.2.3 (Tab 3/Q.711) 655 |Indication|ANSI-T1.112 Chap 2.1.1.2.3 (Tab 3/T1.112.1) 656 ------------+----------+------------------------------------------- 657 N-EXPEDITED |Request |ITU-Q.711 Chap 6.1.1.2.3 (Tab 4/Q.711) 658 DATA |Indication|ANSI-T1.112 Chap 2.1.1.2.3 (Tab 4/T1.112.1) 659 ------------+----------+------------------------------------------- 660 N-RESET |Request |ITU-Q.711 Chap 6.1.1.2.3 (Tab 5/Q.711) 661 |Indication|ANSI-T1.112 Chap 2.1.1.2.3 (Tab 5/T1.112.1) 662 |Response | 663 |Confirm | 664 ------------+----------+------------------------------------------- 665 N-DISCONNECT|Request |ITU-Q.711 Chap 6.1.1.2.4 (Tab 6/Q.711) 666 |Indication|ANSI-T1.112 Chap 2.1.1.2.4 (Tab 6/T1.112.1) 667 ------------+----------+------------------------------------------- 668 N-INFORM |Request |ITU-Q.711 Chap 6.1.1.3.2 (Tab 8/Q.711) 669 |Indication|ANSI-T1.112 Chap 2.1.1.2.5 (Tab 6A/T1.112.1) 670 ------------+----------+------------------------------------------- 671 N-UNITDATA |Request |ITU-Q.711 Chap 6.2.2.3.1 (Tab 12/Q.711) 672 |Indication|ANSI-T1.112 Chap 2.2.2.3.1 (Tab 8A/T1.112.1) 673 ------------+----------+------------------------------------------- 674 N-NOTICE |Indication|ITU-Q.711 Chap 6.2.2.3.2 (Tab 13/Q.711) 675 | |ANSI-T1.112 Chap 2.2.2.3.2 (Tab 8B/T1.112.1) 676 ------------+----------+-------------------------------------------- 677 N-STATE |Request |ITU-Q.711 Chap 6.3.2.3.2 (Tab 16/Q.711) 678 |Indication|ANSI-T1.112 Chap 2.3.2.3.2 (Tab 8E/T1.112.1) 679 ------------+----------+-------------------------------------------- 680 N-PCSTATE |Indication|ITU-Q.711 Chap 6.3.2.3.3 (Tab 17/Q.711) 681 | |ANSI-T1.112 Chap 2.3.2.3.4 (Tab 8G/T1.112.1) 682 ------------+----------+-------------------------------------------- 683 N-COORD |Request |ITU-Q.711 Chap 6.3.2.3.1 (Tab 15/Q.711) 684 |Indication|ANSI-T1.112 Chap 2.3.2.3.3 (Tab 8F/T1.112.1) 685 |Response | 686 |Confirm | 688 1.6.2 Definition of the lower boundary 690 The upper layer primitives provided by the SCTP are provided in 691 [SCTP]. 693 1.6.3 Definition of the Boundary between SUA and Layer Management 695 M-SCTP_ESTABLISH request 696 Direction: LM -> SUA 697 Purpose: LM requests ASP to establish an SCTP association with its 698 peer. 700 M-STCP_ESTABLISH confirm 701 Direction: SUA -> LM 702 Purpose: ASP confirms to LM that it has established an SCTP 703 association with its peer. 705 M-SCTP_ESTABLISH indication 706 Direction: SUA -> LM 707 Purpose: SUA informs LM that a remote ASP has established an SCTP 708 association. 710 M-SCTP_RELEASE request 711 Direction: LM -> SUA 712 Purpose: LM requests ASP to release an SCTP association with its 713 peer. 715 M-SCTP_RELEASE confirm 716 Direction: SUA -> LM 717 Purpose: ASP confirms to LM that it has released SCTP association 718 with its peer. 720 M-SCTP_RELEASE indication 721 Direction: SUA -> LM 722 Purpose: SUA informs LM that a remote ASP has released an SCTP 723 Association or the SCTP association has failed. 725 M-SCTP RESTART indication 726 Direction: SUA -> LM 727 Purpose: SUA informs LM that an SCTP restart indication has been 728 received. 730 M-SCTP_STATUS request 731 Direction: LM -> SUA 732 Purpose: LM requests SUA to report the status of an SCTP 733 association. 735 M-SCTP_STATUS confirm 736 Direction: SUA -> LM 737 Purpose: SUA responds with the status of an SCTP association. 739 M-SCTP STATUS indication 740 Direction: SUA -> LM 741 Purpose: SUA reports the status of an SCTP association. 743 M-ASP_STATUS request 744 Direction: LM -> SUA 745 Purpose: LM requests SUA to report the status of a local or remote 746 ASP. 748 M-ASP_STATUS confirm 749 Direction: SUA -> LM 750 Purpose: SUA reports status of local or remote ASP. 752 M-AS_STATUS request 753 Direction: LM -> SUA 754 Purpose: LM requests SUA to report the status of an AS. 756 M-AS_STATUS confirm 757 Direction: SUA -> LM 758 Purpose: SUA reports the status of an AS. 760 M-NOTIFY indication 761 Direction: SUA -> LM 762 Purpose: SUA reports that it has received a Notify message from its 763 peer. 765 M-ERROR indication 766 Direction: SUA -> LM 767 Purpose: SUA reports that it has received an Error message from its 768 peer or that a local operation has been unsuccessful. 770 M-ASP_UP request 771 Direction: LM -> SUA 772 Purpose: LM requests ASP to start its operation and send an ASP Up 773 message to its peer. 775 M-ASP_UP confirm 776 Direction: SUA -> LM 777 Purpose: ASP reports that is has received an ASP UP Ack message 778 from its peer. 780 M-ASP_UP indication 781 Direction: SUA -> LM 782 Purpose: SUA reports it has successfully processed an incoming ASP 783 Up message from its peer. 785 M-ASP_DOWN request 786 Direction: LM -> SUA 787 Purpose: LM requests ASP to stop its operation and send an ASP Down 788 message to its peer. 790 M-ASP_DOWN confirm 791 Direction: SUA -> LM 792 Purpose: ASP reports that is has received an ASP Down Ack message 793 from its peer. 795 M-ASP_DOWN indication 796 Direction: SUA -> LM 797 Purpose: SUA reports it has successfully processed an incoming ASP 798 Down message from its peer, or the SCTP association has 799 been lost/reset. 801 M-ASP_ACTIVE request 802 Direction: LM -> SUA 803 Purpose: LM requests ASP to send an ASP Active message to its peer. 805 M-ASP_ACTIVE confirm 806 Direction: SUA -> LM 807 Purpose: ASP reports that is has received an ASP Active Ack message 808 from its peer. 810 M-ASP_ACTIVE indication 811 Direction: SUA -> LM 812 Purpose: SUA reports it has successfully processed an incoming ASP 813 Active message from its peer. 815 M-ASP_INACTIVE request 816 Direction: LM -> SUA 817 Purpose: LM requests ASP to send an ASP Inactive message to its 818 peer. 820 M-ASP_INACTIVE confirm 821 Direction: LM -> SUA 822 Purpose: ASP reports that is has received an ASP Inactive 823 Ack message from its peer. 825 M-ASP_INACTIVE indication 826 Direction: SUA -> LM 827 Purpose: SUA reports it has successfully processed an incoming ASP 828 Inactive message from its peer. 830 M-AS_ACTIVE indication 831 Direction: SUA -> LM 832 Purpose: SUA reports that an AS has moved to the AS-ACTIVE state. 834 M-AS_INACTIVE indication 835 Direction: SUA -> LM 836 Purpose: SUA reports that an AS has moved to the AS-INACTIVE state. 838 M-AS_DOWN indication 839 Direction: SUA -> LM 840 Purpose: SUA reports that an AS has moved to the AS-DOWN state. 842 If the SUA layer supports dynamic registration of Routing Key, the 843 layer MAY support the following additional primitives: 845 M-RK_REG request 846 Direction: LM -> SUA 847 Purpose: LM requests ASP to register RK(s) with its peer by sending 848 REG REQ message 850 M-RK_REG confirm 851 Direction: SUA -> LM 852 Purpose: ASP reports that it has received REG RSP message with 853 registration status as successful from its peer. 855 M-RK_REG indication 856 Direction: SUA -> LM 857 Purpose: SUA informs LM that it has successfully processed an 858 incoming REG REQ message. 860 M-RK_DEREG request 861 Direction: LM -> SUA 862 Purpose: LM requests ASP to deregister RK(s) with its peer by 863 sending DEREG REQ message. 865 M-RK_DEREG confirm 866 Direction: SUA -> LM 867 Purpose: ASP reports that it has received DEREG RESP message with 868 deregistration status as successful from its peer. 870 M-RK_DEREG indication 871 Direction: SUA -> LM 872 Purpose: SUA informs LM that it has successfully processed an 873 incoming DEREG REQ from its peer. 875 2 Conventions 877 The keywords MUST, MUST NOT, REQUIRED, SHALL, SHALL NOT, SHOULD, 878 SHOULD NOT, RECOMMENDED, NOT RECOMMENDED, MAY, and OPTIONAL, when 879 they appear in this document, are to be interpreted as described in 880 [RFC2119]. 882 3 Protocol Elements 884 The general message format includes a Common Message Header together 885 with a list of zero or more parameters as defined by the Message 886 Type. 888 For forward compatibility, all Message Types may have attached 889 parameters even if none are specified in this version. 891 The Reserved field is set to 0 in messages sent and is not to be 892 examined in messages received. 894 3.1 Common Message Header 896 The protocol messages for the SCCP-User Adaptation Protocol requires 897 a message structure which contains a version, message class, message 898 type, message length and message contents. This message header is 899 common among all signalling protocol adaptation layers: 901 0 1 2 3 902 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 903 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 904 | Version | Reserved | Message Class | Message Type | 905 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 906 | Message Length | 907 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 908 | Message Data | 910 Note that the 'data' portion of SUA messages SHALL contain SCCP-User 911 data, not the encapsulated SCCP message. 913 Optional parameters can only occur at most once in an SUA message. 915 3.1.1 SUA Protocol Version 917 The version field (ver) contains the version of the SUA adaptation 918 layer. The supported versions are: 920 1 SUA version 1.0 922 3.1.2 Message Classes 924 Message Classes 926 0 SUA Management (MGMT) Message 927 1 Reserved 928 2 Signalling Network Management (SNM) Messages 929 3 ASP State Maintenance (ASPSM) Messages 930 4 ASP Traffic Maintenance (ASPTM) Messages 931 5 Reserved 932 6 Reserved 933 7 Connectionless Messages 934 8 Connection-Oriented Messages 935 9 Routing Key Management (RKM) Messages. 936 10 - 127 Reserved by the IETF 937 128 - 255 Reserved for IETF-Defined Message Class Extensions 939 3.1.3 Message Types 941 SUA Management Messages 943 0 Error (ERR) 944 1 Notify (NTFY) 945 2 - 127 Reserved by the IETF 946 128- 255 Reserved for IETF-Defined Message Class Extensions 948 Signalling Network Management (SNM) Messages 950 0 Reserved 951 1 Destination Unavailable (DUNA) 952 2 Destination Available (DAVA) 953 3 Destination State Audit (DAUD) 954 4 Network Congestion (SCON) 955 5 Destination User Part Unavailable (DUPU) 956 6 Destination Restricted (DRST) 957 7 - 127 Reserved by the IETF 958 128 - 255 Reserved for IETF-Defined Message Class Extensions 960 Application Server Process State Maintenance (ASPSM) Messages 962 0 Reserved 963 1 ASP Up (UP) 964 2 ASP Down (DOWN) 965 3 Heartbeat (BEAT) 966 4 ASP Up Ack (UP ACK) 967 5 ASP Down Ack (DOWN ACK) 968 6 Heartbeat Ack (BEAT ACK) 969 7 - 127 Reserved by the IETF 970 128 - 255 Reserved for IETF-Defined Message Class Extensions 972 ASP Traffic Maintenance (ASPTM) Messages 974 0 Reserved 975 1 ASP Active (ACTIVE) 976 2 ASP Inactive (INACTIVE) 977 3 ASP Active Ack (ACTIVE ACK) 978 4 ASP Inactive Ack (INACTIVE ACK) 979 5 - 127 Reserved by the IETF 980 128 - 255 Reserved for IETF-Defined Message Class Extensions 982 Routing Key Management (RKM) Messages 984 0 Reserved 985 1 Registration Request (REG REQ) 986 2 Registration Response (REG RSP) 987 3 Deregistration Request (DEREG REQ) 988 4 Deregistration Response (DEREG RSP) 989 5 - 127 Reserved by the IETF 990 128 - 255 Reserved for IETF-Defined Message Class Extensions 992 Connectionless (CL) Messages 994 0 Reserved 995 1 Connectionless Data Transfer (CLDT) 996 2 Connectionless Data Response (CLDR) 997 3 - 127 Reserved by the IETF 998 128 - 255 Reserved for IETF-Defined Message Class Extensions 1000 Connection-Oriented (CO) Messages 1002 0 Reserved 1003 1 Connection Request (CORE) 1004 2 Connection Acknowledge (COAK) 1005 3 Connection Refused (COREF) 1006 4 Release Request (RELRE) 1007 5 Release Complete (RELCO) 1008 6 Reset Confirm (RESCO) 1009 7 Reset Request (RESRE) 1010 8 Connection Oriented Data Transfer (CODT) 1011 9 Connection Oriented Data Acknowledge (CODA) 1012 10 Connection Oriented Error (COERR) 1013 11 Inactivity Test (COIT) 1014 12 - 127 Reserved by the IETF 1015 128 - 255 Reserved for IETF-Defined Message Class Extensions 1017 3.1.4 Message Length 1019 The Message Length defines the length of the message in octets, 1020 including the header and including all padding bytes. Message Length 1021 is a 32-bit identifier. 1023 3.1.5 Tag-Length-Value Format 1025 SUA messages consist of a Common Header followed by zero or more 1026 parameters, as defined by the message type. The Tag-Length-Value 1027 (TLV) parameters contained in a message are defined in a Tag-Length- 1028 Value format as shown below. 1030 0 1 2 3 1031 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1032 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1033 | Parameter Tag | Parameter Length | 1034 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1035 \ \ 1036 / Parameter Value / 1037 \ \ 1038 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1040 Parameter Tag: 16 bits (unsigned integer) 1042 Tag field is a 16-bit identifier of the type of parameter. It 1043 takes a value of 0 to 65535. 1045 Parameter Length: 16 bits (unsigned integer) 1047 The Parameter Length field contains the size of the parameter in 1048 bytes, including the Parameter Tag, Parameter Length, and 1049 Parameter Value fields. The Parameter Length does not include any 1050 padding bytes. However, composite parameters will contain all 1051 padding bytes, since all parameters contained within this 1052 composite parameter will be considered multiples of 4 bytes. 1054 Parameter Value: variable-length. 1056 The Parameter Value field contains the actual information to be 1057 trasnfered in the parameter. 1059 The total length of a parameter (including Tag, Parameter Length 1060 and Value fields) MUST be a multiple of 4 bytes. If the length of 1061 the parameter is not a multiple of 4 bytes, the sender pads the 1062 parameter at the end (i.e., after the Parameter Value field) with 1063 all zero bytes. The length of the padding is NOT included in the 1064 parameter length field. A sender should NEVER pad with more than 3 1065 bytes. The receiver MUST ignore the padding bytes. 1067 Implementation note: the use of TLV in principle allows the 1068 parameters to be placed in a random order in the message. However, 1069 some guidelines should be considered for easy processing in the 1070 following order: 1072 - Parameters needed to correctly process other message 1073 parameters, preferably should precede these parameters (such 1074 as Routing Context). 1075 - Mandatory parameters preferably SHOULD precede any optional 1076 parameters. 1077 - The data parameter will normally be the final one in the 1078 message. 1079 - The receiver SHOULD accept parameters in any order, except 1080 where explicitly mandated. 1082 3.2 SUA Connectionless Messages 1084 The following section describes the SUA Connectionless transfer 1085 messages and parameter contents. The general message format 1086 includes a Common Message Header together with a list of zero or 1087 more parameters as defined by the Message Type. All Message Types 1088 can have attached parameters. 1090 3.2.1 Connectionless Data Transfer (CLDT) 1092 This message transfers data between one SUA to another. 1094 0 1 2 3 1095 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1096 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1097 | Tag = 0x0006 | Length | 1098 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1099 / Routing Context / 1100 \ \ 1101 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1102 | Tag = 0x0115 | Length | 1103 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1104 | Protocol Class | 1105 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1106 | Tag = 0x0102 | Length | 1107 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1108 / Source Address / 1109 \ \ 1110 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1111 | Tag = 0x0103 | Length | 1112 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1113 / Destination Address / 1114 \ \ 1115 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1116 | Tag = 0x0116 | Length | 1117 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1118 | Sequence Control | 1119 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1120 | Tag = 0x0101 | Length | 1121 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1122 | SS7 Hop Count | 1123 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1124 | Tag = 0x0113 | Length | 1125 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1126 | Importance | 1127 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1128 | Tag = 0x0114 | Length | 1129 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1130 | Message Priority | 1131 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1132 | Tag = 0x0013 | Length | 1133 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1134 | Correlation ID | 1135 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1136 | Tag = 0x0117 | Length | 1137 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1138 | Segmentation | 1139 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1140 | Tag = 0x010b | Length | 1141 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1142 / Data / 1143 \ \ 1144 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1146 Parameters 1147 Routing Context Mandatory 1148 Protocol Class Mandatory 1149 Source Address Mandatory 1150 Destination Address Mandatory 1151 Sequence Control Mandatory 1152 SS7 Hop Count Optional 1153 Importance Optional 1154 Message Priority Optional 1155 Correlation ID Optional 1156 Segmentation Optional 1157 Data Mandatory 1159 Implementation note: This message covers the following SCCP 1160 messages: unitdata (UDT), extended unitdata (XUDT), long unitdata 1161 (LUDT). 1163 3.2.2 Connectionless Data Response (CLDR) 1165 This message is used as a response message by the peer to report 1166 errors in the received CLDT message, when the return on error option 1167 is set. 1169 0 1 2 3 1170 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1171 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1172 | Tag = 0x0006 | Length | 1173 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1174 / Routing Context / 1175 \ \ 1176 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1177 | Tag = 0x0106 | Length | 1178 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1179 | SCCP Cause | 1180 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1181 | Tag = 0x0102 | Length | 1182 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1183 / Source Address / 1184 \ \ 1185 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1186 | Tag = 0x0103 | Length | 1187 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1188 / Destination Address / 1189 \ \ 1190 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1191 | Tag = 0x0101 | Length | 1192 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1193 | SS7 Hop Count | 1194 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1195 | Tag = 0x0113 | Length | 1196 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1197 | Importance | 1198 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1199 | Tag = 0x0114 | Length | 1200 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1201 | Message Priority | 1202 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1203 | Tag = 0x0013 | Length | 1204 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1205 | Correlation ID | 1206 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1207 | Tag = 0x0117 | Length | 1208 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1209 | Segmentation | 1210 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1211 | Tag = 0x010b | Length | 1212 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- 1213 / Data / 1214 \ \ 1215 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1217 Parameters 1218 Routing Context Mandatory 1219 SCCP Cause Mandatory 1220 Source Address Mandatory 1221 Destination Address Mandatory 1222 SS7 Hop Count Optional 1223 Importance Optional 1224 Message Priority Optional 1225 Correlation ID Optional 1226 Segmentation Optional 1227 Data Optional 1229 Implementation note: This message covers the following SCCP 1230 messages: unitdata service (UDTS), extended unitdata service (XUDTS) 1231 and long unitdata service (LUDTS). 1233 3.3 Connection Oriented Messages 1235 3.3.1 Connection Oriented Data Transfer (CODT) 1237 This message transfers data between one SUA to another for 1238 connection-oriented service. 1240 0 1 2 3 1241 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1242 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1243 | Tag = 0x0006 | Length | 1244 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1245 / Routing Context / 1246 \ \ 1247 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1248 | Tag = 0x0107 | Length | 1249 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1250 | Sequence Number | 1251 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1252 | Tag = 0x0105 | Length | 1253 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1254 | Destination Reference Number | 1255 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1256 | Tag = 0x0114 | Length | 1257 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1258 | Message Priority | 1259 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1260 | Tag = 0x0013 | Length | 1261 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1262 | Correlation ID | 1263 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1264 | Tag = 0x010b | Length | 1265 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1266 / Data / 1267 \ \ 1268 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1270 Parameters 1271 Routing Context Mandatory 1272 Sequence Number Optional *1 1273 Destination Reference Number Mandatory 1274 Message Priority Optional 1275 Correlation ID Optional 1276 Data Mandatory 1278 NOTE *1: This parameter is not present in case of Expedited Data 1279 (ED). 1281 Implementation note: In order for the CODT to represent DT1, DT2 and 1282 ED messages, the following conditions MUST be met: 1284 DT1 is represented by a CODT when: 1285 Sequence Number parameter is present (contains "more" indicator). 1287 DT2 is represented by a CODT when: 1288 Sequence Number parameter is present (contains P(S), P(R) and more 1289 indicator) 1291 ED is represented by a CODT with: 1292 Sequence Number parameter is not present 1294 3.3.2 Connection Oriented Data Acknowledge (CODA) 1296 The peer uses this message to acknowledge receipt of data. This 1297 message is used only with protocol class 3. 1299 0 1 2 3 1300 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1301 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1302 | Tag = 0x0006 | Length | 1303 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1304 / Routing Context / 1305 \ \ 1306 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1307 | Tag = 0x0105 | Length | 1308 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1309 | Destination Reference Number | 1310 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1311 | Tag = 0x0108 | Length | 1312 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1313 | Receive Sequence Number | 1314 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1315 | Tag = 0x010A | Length | 1316 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1317 | Credit | 1318 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1320 Parameters 1321 Routing Context Mandatory 1322 Destination Reference Number Mandatory 1323 Receive Sequence Number Optional *1 1324 Credit Mandatory *1 1326 NOTE *1: Mandatory when representing Data Acknowledgement (AK). 1328 Implementation note: In order for the CODA to represent DA and EA 1329 messages, the following conditions MUST be met: 1331 DA is represented by a CODA when: 1332 Receive Sequence Number parameter is present (contains P(S), P(R) 1333 and more indicator) 1335 EA is represented by a CODA when: 1336 Receive Sequence Number parameter is not present 1338 3.3.3 Connection Request (CORE) 1340 This message is used for establishing a signalling connection 1341 between two peer endpoints. 1343 0 1 2 3 1344 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1345 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1346 | Tag = 0x0006 | Length | 1347 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1348 / Routing Context / 1349 \ \ 1350 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1351 | Tag = 0x0115 | Length | 1352 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1353 | Protocol Class | 1354 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1355 | Tag = 0x0104 | Length | 1356 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1357 | Source Reference Number | 1358 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1359 | Tag = 0x0103 | Length | 1360 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1361 / Destination Address / 1362 \ \ 1363 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1364 | Tag = 0x0116 | Length | 1365 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1366 | Sequence Control | 1367 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1368 | Tag = 0x0107 | Length | 1369 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1370 | Sequence Number | 1371 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1372 | Tag = 0x0102 | Length | 1373 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1374 / Source Address / 1375 \ \ 1376 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1377 | Tag = 0x0101 | Length | 1378 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1379 | SS7 Hop Count | 1380 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1381 | Tag = 0x0113 | Length | 1382 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1383 | Importance | 1384 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1385 | Tag = 0x0114 | Length | 1386 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1387 | Message Priority | 1388 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1389 | Tag = 0x010A | Length | 1390 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1391 | Credit | 1392 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1393 | Tag = 0x010b | Length | 1394 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1395 / Data / 1396 \ \ 1397 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1399 Parameters 1400 Routing Context Mandatory 1401 Protocol Class Mandatory 1402 Source Reference Number Mandatory 1403 Destination Address Mandatory 1404 Sequence Control Mandatory 1405 Sequence Number Optional *1 1406 Source Address Optional 1407 SS7 Hop Count Optional 1408 Importance Optional 1409 Message Priority Optional 1410 Credit Optional *1 1411 Data Optional 1413 NOTE *1: Manditory for protocol class 3 only. 1415 Implementation note: This message covers the following SCCP message: 1416 Connection Request (CR). 1418 3.3.4 Connection Acknowledge (COAK) 1420 This message is used to acknowledge a connection request from the 1421 peer endpoint. 1423 0 1 2 3 1424 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1425 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1426 | Tag = 0x0006 | Length | 1427 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1428 / Routing Context / 1429 \ \ 1430 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1431 | Tag = 0x0115 | Length | 1432 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1433 | Protocol Class | 1434 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1435 | Tag = 0x0105 | Length | 1436 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1437 | Destination Reference Number | 1438 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1439 | Tag = 0x0104 | Length | 1440 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1441 | Source Reference Number | 1442 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1443 | Tag = 0x01116 | Length | 1444 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1445 | Sequence Control | 1446 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1447 | Tag = 0x010A | Length | 1448 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1449 | Credit | 1450 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1451 | Tag = 0x0102 | Length | 1452 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1453 / Source Address / 1454 \ \ 1455 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1456 | Tag = 0x0113 | Length | 1457 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1458 | Importance | 1459 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1460 | Tag = 0x0114 | Length | 1461 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1462 | Message Priority | 1463 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1464 | Tag = 0x0103 | Length | 1465 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1466 / Destination Address / 1467 \ \ 1468 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1469 | Tag = 0x010b | Length | 1470 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1471 / Data / 1472 \ \ 1473 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1475 Parameters 1476 Routing Context Mandatory 1477 Protocol Class Mandatory 1478 Destination Reference Number Mandatory 1479 Source Reference Number Mandatory 1480 Sequence Control Mandatory 1481 Credit Mandatory *2 1482 Source Address Optional 1483 Importance Optional 1484 Message Priority Optional 1485 Destination Address Optional *1 1486 Data Optional 1488 NOTE *1: Destination Address parameter will be present in case 1489 that the received CORE message conveys the Source 1490 Address parameter. 1492 NOTE *2: Only applicable for protocol class 3. 1494 Implementation note: This message covers the following SCCP message: 1495 Connection Confirm (CC). 1497 3.3.5 Connection Refused (COREF) 1499 This message is used to refuse a connection request between two peer 1500 endpoints. 1502 0 1 2 3 1503 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1504 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1505 | Tag = 0x0006 | Length | 1506 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1507 / Routing Context / 1508 \ \ 1509 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1510 | Tag = 0x0105 | Length | 1511 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1512 | Destination Reference Number | 1513 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1514 | Tag = 0x0106 | Length | 1515 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1516 | SCCP Cause | 1517 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1518 | Tag = 0x0102 | Length | 1519 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1520 / Source Address / 1521 \ \ 1522 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1523 | Tag = 0x0103 | Length | 1524 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1525 / Destination Address / 1526 \ \ 1527 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1528 | Tag = 0x0113 | Length = 8 | 1529 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1530 | Importance | 1531 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1532 | Tag = 0x010b | Length | 1533 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1534 / Data / 1535 \ \ 1536 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1538 Parameters 1539 Routing Context Mandatory 1540 Destination Reference Number Mandatory 1541 SCCP Cause Mandatory 1542 Source Address Optional 1543 Destination Address Optional *1 1544 Importance Optional 1545 Data Optional 1547 Note *1: Destination Address parameter will be present in case 1548 that the received CORE message conveys the Source Address 1549 parameter. 1551 Implementation note: This message covers the following SCCP message: 1552 Connection REFused (CREF). 1554 3.3.6 Release Request (RELRE) 1556 This message is used to request a signalling connection between two 1557 peer endpoints be released. All associated resources can then be 1558 released. 1560 0 1 2 3 1561 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1562 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1563 | Tag = 0x0006 | Length | 1564 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1565 / Routing Context / 1566 \ \ 1567 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1568 | Tag = 0x0105 | Length | 1569 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1570 | Destination Reference Number | 1571 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1572 | Tag = 0x0104 | Length | 1573 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1574 | Source Reference Number | 1575 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1576 | Tag = 0x0106 | Length | 1577 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1578 | SCCP Cause | 1579 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1580 | Tag = 0x0113 | Length = 8 | 1581 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1582 | Importance | 1583 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1584 | Tag = 0x010b | Length | 1585 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1586 / Data / 1587 \ \ 1588 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1590 Parameters 1591 Routing Context Mandatory 1592 Destination Reference Number Mandatory 1593 Source Reference Number Mandatory 1594 SCCP Cause Mandatory 1595 Importance Optional 1596 Data Optional 1598 Implementation note: This message covers the following SCCP message: 1599 connection ReLeaSeD (RLSD). 1601 3.3.7 Release Complete (RELCO) 1603 This message is used to acknowledge the release of a signalling 1604 connection between two peer endpoints. All associated resources 1605 should be released. 1607 0 1 2 3 1608 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1609 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1610 | Tag = 0x0006 | Length | 1611 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1612 / Routing Context / 1613 \ \ 1614 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1615 | Tag = 0x0105 | Length | 1616 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1617 | Destination Reference Number | 1618 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1619 | Tag = 0x0104 | Length | 1620 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1621 | Source Reference Number | 1622 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1623 | Tag = 0x0113 | Length = 8 | 1624 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1625 | Importance | 1626 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1628 Parameters 1629 Routing Context Mandatory 1630 Destination Reference Number Mandatory 1631 Source Reference Number Mandatory 1632 Importance Optional 1634 Implementation note: This message covers the following SCCP message: 1635 ReLease Complete (RLC). 1637 3.3.8 Reset Request (RESRE) 1639 This message is used to indicate that the sending SCCP/SUA wants to 1640 initiate a reset procedure (re-initialization of sequence numbers) 1641 to the peer endpoint. 1643 0 1 2 3 1644 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1645 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1646 | Tag = 0x0006 | Length | 1647 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1648 / Routing Context / 1649 \ \ 1650 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1651 | Tag = 0x0105 | Length | 1652 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1653 | Destination Reference Number | 1654 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1655 | Tag = 0x0104 | Length | 1656 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1657 | Source Reference Number | 1658 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1659 | Tag = 0x0106 | Length | 1660 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1661 | SCCP Cause | 1662 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1664 Parameters 1665 Routing Context Mandatory 1666 Destination Reference Number Mandatory 1667 Source Reference Number Mandatory 1668 SCCP Cause Mandatory 1670 Implementation note: This message covers the following SCCP message: 1671 ReSet Request (RSR). 1673 3.3.9 Reset Confirm (RESCO) 1675 This message is used to confirm the Reset Request. 1677 0 1 2 3 1678 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1679 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1680 | Tag = 0x0006 | Length | 1681 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1682 / Routing Context / 1683 \ \ 1684 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1685 | Tag = 0x0105 | Length | 1686 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1687 | Destination Reference Number | 1688 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1689 | Tag = 0x0104 | Length | 1690 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1691 | Source Reference Number | 1692 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1694 Parameters 1695 Routing Context Mandatory 1696 Destination Reference Number Mandatory 1697 Source Reference Number Mandatory 1699 Implementation note: This message covers the following SCCP message: 1700 ReSet Confirmation (RSC). 1702 3.3.10 Connection Oriented Error (COERR) 1704 The COERR message is sent to indicate a protocol data unit error. 1706 0 1 2 3 1707 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1708 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1709 | Tag = 0x0006 | Length | 1710 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1711 / Routing Context / 1712 \ \ 1713 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1714 | Tag = 0x0105 | Length | 1715 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1716 | Destination Reference Number | 1717 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1718 | Tag = 0x0106 | Length | 1719 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1720 | SCCP Cause | 1721 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1723 Parameters 1724 Routing Context Mandatory 1725 Destination Reference Number Mandatory 1726 SCCP Cause Mandatory 1728 Implementation note: This message covers the following SCCP message: 1729 Protocol Data Unit ERRor (ERR). 1731 3.3.11 Connection Oriented Inactivity Test (COIT) 1733 This message is used for auditing the signalling connection state 1734 and the consistency of connection data at both ends of the 1735 signalling connection. 1737 0 1 2 3 1738 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1739 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1740 | Tag = 0x0006 | Length | 1741 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1742 / Routing Context / 1743 \ \ 1744 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1745 | Tag = 0x0115 | Length | 1746 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1747 | Protocol Class | 1748 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1749 | Tag = 0x0104 | Length | 1750 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1751 | Source Reference Number | 1752 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1753 | Tag = 0x0105 | Length | 1754 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1755 | Destination Reference number | 1756 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1757 | Tag = 0x0107 | Length | 1758 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1759 | Sequence number | 1760 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1761 | Tag = 0x010A | Length | 1762 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1763 | Credit | 1764 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1766 Parameters 1767 Routing Context Mandatory 1768 Protocol Class Mandatory 1769 Source Reference Number Mandatory 1770 Destination Reference number Mandatory 1771 Sequence Number Mandatory *1 1772 Credit Mandatory *1 1774 NOTE *1: Information in these parameter fields reflects those 1775 values sent in the last data form 2 or data 1776 acknowledgement message. They are ignored if the protocol 1777 class indicates class 2. 1779 Implementation note: This message covers the following SCCP message: 1780 Inactivity Test (IT). 1782 3.4 Signalling Network Management (SNM) Messages 1784 3.4.1 Destination Unavailable (DUNA) 1786 In the scope of SUA, this message is covered by the PC- or N-state 1787 indication passed between SCCP and local SCCP-user. The DUNA message 1788 is sent from the SG or relay node to all concerned ASPs (servicing 1789 SCCP-users considered local to the SG or relay node, see chapter 1790 1.3.1.1), when a destination or SCCP-user has become unreachable. 1791 The SUA-User at the ASP is expected to stop traffic to the affected 1792 destination or SCCP-user through the SG or relay node initiating the 1793 DUNA. 1795 The format for DUNA Message parameters is as follows: 1797 0 1 2 3 1798 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1799 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1800 | Tag = 0x0006 | Length | 1801 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1802 / Routing Context / 1803 \ \ 1804 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1805 | Tag = 0x0012 | Length | 1806 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1807 / Affected Point Code / 1808 \ \ 1809 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1810 | Tag = 0x8003 | Length | 1811 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1812 | SSN | 1813 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1814 | Tag = 0x0112 | Length | 1815 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1816 | SMI | 1817 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1818 | Tag = 0x0004 | Length | 1819 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1820 / Info String / 1822 \ \ 1823 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1825 Parameters 1826 Routing Context Optional 1827 Affected Point Code Mandatory *1 1828 SSN Optional *1 1829 SMI Optional 1830 Info String Optional 1832 Note 1: When the SSN is included, the DUNA message 1833 corresponds to the SCCP N-STATE primitive. When SSN 1834 is not, the DUNA message corresponds to the SCCP N- 1835 PCSTATE primitive. When SSN is not, the DUNA 1836 message corresponds to the SCCP N-PCSTATE primitive. 1838 3.4.2 Destination Available (DAVA) 1840 In the scope of SUA, this message is covered by the PC- and N-state 1841 indication passed between SCCP and local SCCP-user. The DAVA message 1842 is sent from the SG or relay node to all concerned ASPs (servicing 1843 SCCP-users considered local to the SG or relay node, see chapter 1844 1.3.1.1) to indicate that a destination (PC or SCCP-user) is now 1845 reachable. The ASP SUA-User protocol is expected to resume traffic 1846 to the affected destination through the SG or relay node initiating 1847 the DAVA. 1849 0 1 2 3 1850 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1851 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1852 | Tag = 0x0006 | Length | 1853 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1854 / Routing Context / 1855 \ \ 1856 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1857 | Tag = 0x0012 | Length | 1858 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1859 / Affected Point Code / 1860 \ \ 1861 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1862 | Tag = 0x8003 | Length | 1863 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1864 | SSN | 1865 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1866 | Tag = 0x0112 | Length | 1867 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1868 | SMI | 1869 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1870 | Tag = 0x0004 | Length | 1871 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1872 / Info String / 1874 \ \ 1875 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1877 Parameters 1878 Routing Context Optional 1879 Affected Point Code Mandatory *1 1880 SSN Optional *1 1881 SMI Optional 1882 Info String Optional 1884 Note 1: When the SSN is included, the DAVA message corresponds to 1885 the SCCP N-STATE primitive. When SSN is not included, the 1886 DAVA message corresponds to the SCCP N-PCSTATE primitive. 1887 The Affected Point Code can only contain one point code 1888 when SSN is present. 1890 3.4.3 Destination State Audit (DAUD) 1892 The DAUD message can be sent from the ASP to the SG (or relay node) 1893 to query the availability state of the routes to an affected 1894 destination. A DAUD may be sent periodically after the ASP has 1895 received a DUNA, until a DAVA is received. The DAUD can also be sent 1896 when an ASP recovers from isolation from the SG (or relay node). 1898 0 1 2 3 1899 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1900 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1901 | Tag = 0x0006 | Length | 1902 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1903 / Routing Context / 1904 \ \ 1905 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1906 | Tag = 0x0012 | Length | 1907 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1908 / Affected Point Code / 1909 \ \ 1910 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1911 | Tag = 0x8003 | Length | 1912 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1913 | SSN | 1914 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1915 | Tag = 0x010c | Length | 1916 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1917 | User/Cause | 1918 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1919 | Tag = 0x0004 | Length | 1920 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1921 / Info String / 1923 \ \ 1924 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1926 Parameters 1927 Routing Context Optional 1928 Affected Point Code Mandatory *1 1929 SSN Optional *1 1930 User / Cause Optional 1931 Info String Optional 1933 Note 1: If the SSN is present, the DAUD is "soliciting" N-STATE 1934 primitives, otherwise it is "soliciting" N-PCSTATE 1935 primitives. 1937 3.4.4 Network Congestion (SCON) 1939 The SCON message can be sent from the SG or relay node to all 1940 concerned ASPs to indicate that the congestion level in the SS7 1941 network to a specified destination has changed. 1943 0 1 2 3 1944 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1945 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1946 | Tag = 0x0006 | Length | 1947 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1948 / Routing Context / 1949 \ \ 1950 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1951 | Tag = 0x0012 | Length | 1952 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1953 / Affected Point Code / 1954 \ \ 1955 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1956 | Tag = 0x8003 | Length | 1957 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1958 | SSN | 1959 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1960 | Tag = 0x0118 | Length | 1961 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1962 | Congestion Level | 1963 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1964 | Tag = 0x0112 | Length | 1965 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1966 | SMI | 1967 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1968 | Tag = 0x0004 | Length | 1969 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1970 / Info String / 1971 \ \ 1972 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1974 Parameters 1975 Routing Context Optional 1976 Affected Point Code Mandatory *1 1977 SSN Optional *1 1978 Congestion Level Mandatory 1979 SMI Optional 1980 Info String Optional 1982 Note 1: When the SSN is included, the SCON message corresponds to 1983 the SCCP N-STATE primitive. When the SSN is not 1984 included, the SCON message corresponds to the SCCP N- 1985 PCSTATE primitive reporting signalling point or network 1986 congestion status. 1988 3.4.5 Destination User Part Unavailable (DUPU) 1990 The DUPU message is used by an SG to inform an ASP that a remote 1991 peer at an SS7 node is unavailable. 1993 The format for DUPU message parameters is as follows: 1995 0 1 2 3 1996 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 1997 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1998 | Tag = 0x0006 | Length | 1999 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2000 / Routing Context / 2001 \ \ 2002 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2003 | Tag = 0x0012 | Length | 2004 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2005 / Affected Point Code / 2006 \ \ 2007 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2008 | Tag = 0x010c | Length | 2009 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2010 | User/Cause | 2011 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2012 | Tag = 0x0004 | Length | 2013 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2014 \ \ 2015 / INFO String / 2016 \ \ 2017 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2019 Parameters 2020 Routing Context Optional 2021 Affected Point Code Mandatory *1 2022 User/Cause Mandatory 2023 Info String Optional 2025 Note 1: The DUPU corresponds to the SCCP N-PCSTATE primitive. 2027 3.4.6 Destination Restricted (DRST) 2029 The DRST message is optionally sent from the SG to all concerned 2030 ASPs to indicate that the SG has determined that one or more 2031 destinations are now restricted from the point of view of the SG, or 2032 in response to a DAUD message if appropriate. The SUA layer at the 2033 ASP is expected to send traffic to the affected destination via an 2034 alternate SG of equal priority, but only if such an alternate route 2035 exists and is available. If the ASP currently considers the affected 2036 destination unavailable, the peer should be informed that traffic to 2037 the affected destination could be resumed. In this case, the SUA 2038 layer should route the traffic through the SG initiating the DRST 2039 message. 2041 This message is optional for the SG to send and it is optional for 2042 the ASP to act on any information received in the message. 2044 0 1 2 3 2045 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2046 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2047 | Tag = 0x0006 | Length | 2048 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2049 / Routing Context / 2050 \ \ 2051 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2052 | Tag = 0x0012 | Length | 2053 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2054 / Affected Point Code / 2055 \ \ 2056 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2057 | Tag = 0x8003 | Length | 2058 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2059 | SSN | 2060 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2061 | Tag = 0x0112 | Length = 8 | 2062 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2063 | Reserved | SMI | 2064 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2065 | Tag = 0x0004 | Length | 2066 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2067 / Info String / 2068 \ \ 2069 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2071 Parameters 2072 Routing Context Optional 2073 Affected Point Code Mandatory *1 2074 SSN Optional *1 2075 SMI Optional *1 2076 Info String Optional 2078 Note 1: The Affected Point Code referes to the node to which 2079 become restricted or which has requested coordinated 2080 service outgage. When SSN is included in the message 2081 parameter, the DRST message corresponds to the SCCP N- 2082 COORD primitive. If the SMI parameter is also included 2083 in the message, the DRST message corresponds to the N- 2084 COORD Request and N-COORD Indication primitives, 2085 otherwise, the DRST message corresponse to the N-COORD 2086 Response and N-COORD Confirm primitives. The Affected 2087 Point Code can only contain one point code when SSN is 2088 present. When SSN is not present, DRST corresponds to N- 2089 PCSTATE primitive. 2091 3.5 Application Server Process State Maintenance Messages 2093 3.5.1 ASP Up (UP) 2095 The ASP UP (UP) message is used to indicate to a remote SUA peer 2096 that the Adaptation layer is up and running. 2098 0 1 2 3 2099 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2100 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2101 | Tag = 0x0011 | Length | 2102 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2103 | ASP Identifier | 2104 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2105 | Tag = 0x0004 | Length | 2106 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2107 / Info String / 2109 \ \ 2110 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2112 Parameters 2113 ASP Identifier Optional *1 2114 Info String Optional 2116 Note 1: ASP Identifier MUST be used where the IPSP/SGP cannot 2117 identify the ASP by pre-configured address/port number 2118 information (e.g., where an ASP is resident on a Host using 2119 dynamic address/port number assignment). 2121 3.5.2 ASP Up Ack (UP ACK) 2123 The ASP UP Ack message is used to acknowledge an ASP-Up message 2124 received from a remote SUA peer. 2126 0 1 2 3 2127 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2128 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2129 | Tag = 0x0004 | Length | 2130 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2131 / Info String / 2133 \ \ 2134 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2136 Parameters 2137 Info String Optional 2139 3.5.3 ASP Down (DOWN) 2141 The ASP Down (DOWN) message is used to indicate to a remote SUA peer 2142 that the adaptation layer is not running. 2144 0 1 2 3 2145 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2146 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2147 | Tag = 0x0004 | Length | 2148 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2149 / Info String / 2151 \ \ 2152 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2154 Parameters 2155 Info String Optional 2157 3.5.4 ASP Down Ack (DOWN ACK) 2159 The ASP DOWN Ack message is used to acknowledge an ASP-Down message 2160 received from a remote SUA peer. 2162 0 1 2 3 2163 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2164 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2165 | Tag = 0x0004 | Length | 2166 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2167 / Info String / 2169 \ \ 2170 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2172 Parameters 2173 Info String Optional 2175 Note: ASP DOWN ACK will always be sent to acknowledge an ASP DOWN. 2177 3.5.5 Heartbeat (BEAT) 2179 The Heartbeat message is optionally used to ensure that the SUA 2180 peers are still available to each other. 2182 The format for the BEAT message is as follows: 2184 0 1 2 3 2185 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2186 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2187 | Tag = 0x0009 | Length | 2188 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2189 / Heartbeat Data / 2190 \ \ 2191 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2193 Parameters 2194 Heartbeat Data Optional 2196 3.5.6 Heartbeat Ack (BEAT ACK) 2197 The Heartbeat ACK message is sent in response to a BEAT message. A 2198 peer MUST send a BEAT ACK in response to a BEAT message. It includes 2199 all the parameters of the received Heartbeat message, without any 2200 change. 2202 The format for the BEAT ACK message is as follows: 2204 0 1 2 3 2205 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2206 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2207 | Tag = 0x0009 | Length | 2208 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2209 / Heartbeat Data / 2210 \ \ 2211 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2213 Parameters 2214 Heartbeat Data Optional 2216 3.6 ASP Traffic Maintenance Messages 2218 3.6.1 ASP Active (ACTIVE) 2220 The ASPAC message is sent by an ASP to indicate to a remote SUA peer 2221 that it is Active and ready to process signalling traffic for a 2222 particular Application Server. 2224 The format for the ACTIVE message is as follows: 2226 0 1 2 3 2227 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2228 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2229 | Tag = 0x000B | Length | 2230 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2231 | Traffic Mode Type | 2232 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2233 | Tag = 0x0006 | Length | 2234 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2235 / Routing Context / 2236 \ \ 2237 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2238 | Tag = 0x0110 | Length | 2239 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2240 | TID Label | 2241 +-------------------------------+-------------------------------+ 2242 | Tag = 0x010F | Length | 2243 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2244 | DRN Label | 2245 +-------------------------------+-------------------------------+ 2246 | Tag = 0x0004 | Length | 2247 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2248 / Info String / 2249 \ \ 2250 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2252 Parameters 2253 Traffic Mode Type Optional 2254 Routing Context Optional 2255 TID Label Optional 2256 DRN Label Optional 2257 Info String Optional 2259 3.6.2 ASP Active Ack (ACTIVE ACK) 2261 The ASPAC Ack message is used to acknowledge an ASP-Active message 2262 received from a remote SUA peer. 2264 The format for the ACTIVE Ack message is as follows: 2266 0 1 2 3 2267 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2268 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2269 | Tag = 0x000B | Length | 2270 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2271 | Traffic Mode Type | 2272 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2273 | Tag = 0x0006 | Length | 2274 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2275 / Routing Context / 2276 \ \ 2277 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2278 | Tag = 0x0004 | Length | 2279 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2280 / Info String / 2281 \ \ 2282 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2284 Parameters 2285 Traffic Mode Type Optional 2286 Routing Context Mandatory 2287 Info String Optional 2289 3.6.3 ASP Inactive (INACTIVE) 2291 The INACTIVE message is sent by an ASP to indicate to a remote SUA 2292 peer that it is no longer processing signalling traffic within a 2293 particular Application Server. 2295 The format for the ASPIA message parameters is as follows: 2297 0 1 2 3 2298 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2299 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2300 | Tag = 0x0006 | Length | 2301 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2302 / Routing Context / 2303 \ \ 2304 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2305 | Tag = 0x0004 | Length | 2306 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2307 / INFO String / 2308 \ \ 2309 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2311 Parameters 2312 Routing Context Optional 2313 INFO String Optional 2315 3.6.4 ASP Inactive Ack (INACTIVE ACK) 2316 The INACTIVE Ack message is used to acknowledge an ASP-Inactive 2317 message received from a remote SUA peer. 2319 The format for the INACTIVE Ack message is as follows: 2321 0 1 2 3 2322 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2323 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2324 | Tag = 0x0006 | Length | 2325 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2326 / Routing Context / 2327 \ \ 2328 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2329 | Tag = 0x0004 | Length | 2330 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2331 / INFO String / 2332 \ \ 2333 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2335 Parameters 2336 Routing Context Optional 2337 INFO String Optional 2339 3.7 SUA Management Messages 2341 These messages are used for managing SUA and the representations of 2342 the SCCP subsystems in the SUA layer. 2344 3.7.1 Error (ERR) 2346 The ERR message is sent between two SUA peers to indicate an error 2347 situation. The Data parameter is optional, possibly used for error 2348 logging and/or debugging. 2350 0 1 2 3 2351 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2352 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2353 | Tag = 0x000C | Length | 2354 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2355 | Error Code | 2356 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2357 | Tag = 0x0006 | Length | 2358 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2359 / Routing Context / 2360 \ \ 2361 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2362 | Tag = 0x0012 | Length | 2363 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2364 | Mask | Affected PC 1 | 2365 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2366 / ... / 2367 \ \ 2368 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2369 | Mask | Affected PC n | 2370 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2371 | Tag = 0x010D | Length = 8 | 2372 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2373 | Network Appearance | 2374 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2375 | Tag = 0x0007 | Length | 2376 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2377 / Diagnostic Info / 2378 \ \ 2379 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2381 Parameters 2382 Error Code Mandatory 2383 Routing Context Mandatory *1 2384 Network Appearance Mandatory *1 2385 Affected Point Code Mandatory *1 2386 Diagnostic Information Optional 2388 Note 1: Only mandatory for specific error codes. 2390 3.7.2 Notify (NTFY) 2392 The Notify message used to provide an autonomous indication of SUA 2393 events to an SUA peer. 2395 0 1 2 3 2396 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2397 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2398 | Tag = 0x000D | Length | 2399 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2400 | Status | 2401 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2402 | Tag = 0x0011 | Length | 2403 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2404 | ASP Identifier | 2405 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- 2406 | Tag = 0x0006 | Length | 2407 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2408 / Routing Context / 2409 \ \ 2410 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2411 | Tag = 0x0004 | Length | 2412 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2413 / Info String / 2415 \ \ 2416 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2418 The NTFY message contains the following parameters: 2420 Parameters 2421 Status Mandatory 2422 ASP Identifier Optional *1 2423 Routing Context Optional 2424 Info String Optional 2426 Note 1: ASP Identifier MUST be used where the IPSP/SGP cannot 2427 identify the ASP by pre-configured address/port number 2428 information (e.g., where an ASP is resident on a Host using 2429 dynamic address/port number assignment). 2431 3.8 Routing Key Management (RKM) Messages 2433 3.8.1 Registration Request (REG REQ) 2435 The REG REQ message is sent by an ASP to indicate to a remote SUA 2436 peer that it wishes to register one or more given Routing Keys with 2437 the remote peer. Typically, an ASP would send this message to an 2438 SGP, and expects to receive a REG RSP message in return with an 2439 associated Routing Context value. 2441 The format for the REG REQ message is as follows: 2443 0 1 2 3 2444 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2445 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2446 | Tag = 0x010E | Length | 2447 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2448 / Routing Key 1 / 2449 \ \ 2450 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2451 / ... / 2452 \ \ 2453 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2454 | Tag = 0x010E | Length | 2455 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2456 / Routing Key n / 2457 \ \ 2458 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2459 | Tag = 0x0109 | Length | 2460 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2461 | ASP Capabilities | 2462 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2464 The REG REQ message contains the following parameters: 2466 Parameters 2467 Routing Key Mandatory *1 2468 ASP Capabilities Optional 2470 Note 1: One or more Routing Key parameters MAY be included in a 2471 single REG REQ message. 2473 3.8.2 Registration Response (REG RSP) 2475 The REG RSP message is sent by an SG to an ASP indicate the result 2476 of a previous REG REQ from an ASP. It contains indications of 2477 success/failure for registration requests and returns a unique 2478 Routing Context value for successful registration requests, to be 2479 used in subsequent SUA Traffic Management protocol messages. 2481 The format for the REG RSP message is as follows: 2483 0 1 2 3 2484 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2485 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2486 | Tag = 0x0014 | Length | 2487 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2488 | Registration Result 1 | 2489 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2490 / ... / 2491 \ \ 2492 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2493 | Tag = 0x0014 | Length | 2494 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2495 | Registration Result n | 2496 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2498 The REG RSP message contains the following parameters: 2500 Parameters 2501 Registration Result Mandatory *1 2503 Note 1: One or more Registration Result parameters MAY be included 2504 in a single REG RSP message. The number of results in a 2505 single REG RSP message can be anywhere from one to the total 2506 number of Routing Key parameters found in the corresponding 2507 REG REQ message. 2509 3.8.3 Deregistration Request (DEREG REQ) 2511 The DEREG REQ message is sent by an ASP to indicate to a remote SUA 2512 peer that it wishes to deregister a given Routing Key. Typically, 2513 an ASP would send this message to an SGP, and expects to receive a 2514 DEREG RSP message in return with the associated Routing Context 2515 value. 2517 The format for the DEREG REQ message is as follows: 2519 0 1 2 3 2520 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2521 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2522 | Tag = 0x0006 | Length | 2523 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2524 / Routing Context / 2525 \ \ 2526 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2528 The DEREG REQ message contains the following parameters: 2530 Parameters 2531 Routing Context Mandatory 2533 3.8.4 Deregistration Response (DEREG RSP) 2534 The DEREG RSP message is used as a response to the DEREG REQ message 2535 from a remote SUA peer. 2537 The format for the DEREG RSP message is as follows: 2539 0 1 2 3 2540 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2541 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2542 | Tag = 0x0015 | Length | 2543 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2544 | Deregistration Result 1 | 2545 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2546 / ... / 2547 \ \ 2548 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2549 | Tag = 0x0015 | Length | 2550 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2551 | Deregistration Result n | 2552 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2554 The DEREG RSP message contains the following parameters: 2556 Parameters 2557 Deregistration Result Mandatory *1 2559 Note 1: One or more Deregistration Result parameters MAY be included 2560 in one DEREG RSP message. The number of results in a single 2561 DEREG RSP message can be anywhere from one to the total 2562 number of number of Routing Context parameters found in the 2563 corresponding DEREG REQ message. 2565 3.9 Common Parameters 2567 These TLV parameters are common across the different adaptation 2568 layers. 2570 Parameter Name Parameter ID 2571 ============== ============ 2572 Reserved 0x0000 2573 Not used in SUA 0x0001 2574 Not used in SUA 0x0002 2575 Not used in SUA 0x0003 2576 Info String 0x0004 2577 Not used in SUA 0x0005 2578 Routing Context 0x0006 2579 Diagnostic Info 0x0007 2580 Not used in SUA 0x0008 2581 Heartbeat Data 0x0009 2582 Not Used in SUA 0x000A 2583 Traffic Mode Type 0x000B 2584 Error Code 0x000C 2585 Status 0x000D 2586 Not used in SUA 0x000E 2587 Not used in SUA 0x000F 2588 Not used in SUA 0x0010 2589 ASP Identifier 0x0011 2590 Affected Point Code 0x0012 2591 Correlation ID 0x0013 2592 Registration Result 0x0014 2593 Deregistration Result 0x0015 2594 Registration Status 0x0016 2595 Deregistration Status 0x0017 2596 Local Routing Key Identifier 0x0018 2598 3.9.1 Not Used 2600 Use of Parameter ID 0x0001 in SUA messages is not supported. 2602 3.9.2 Not Used 2604 Use of Parameter ID 0x0002 in SUA messages is not supported. 2606 3.9.3 Not Used 2608 Use of Parameter ID 0x0002 in SUA messages is not supported. 2610 3.9.4 Info String 2612 The optional INFO String parameter can carry any meaningful UTF-8 2613 [2279] character string along with the message. Length of the INFO 2614 String parameter is from 0 to 255 octets. No procedures are 2615 presently identified for its use but service providers may use the 2616 INFO String for debugging purposes. 2618 0 1 2 3 2619 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2620 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2621 | Tag = 0x0004 | Length | 2622 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2623 / Info String / 2625 \ \ 2626 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2628 3.9.5 Not Used in SUA 2630 Use of Parameter ID 0x0005 in SUA messages is not supported. 2632 3.9.6 Routing Context 2633 0 1 2 3 2634 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2635 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2636 | Tag = 0x0006 | Length | 2637 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2638 / Routing Context / 2639 \ \ 2640 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2642 The Routing Context parameter contains (a list of) 4-byte unsigned 2643 integers indexing the Application Server traffic that the sending 2644 ASP is configured/registered to receive. There is a one-to-one 2645 relationship between an index entry and a Routing Key or AS Name. 2647 An Application Server Process may be configured to process traffic 2648 for more than one logical Application Server. From the perspective 2649 of an ASP, a Routing Context defines a range of signalling traffic 2650 that the ASP is currently configured to receive from the SG. 2652 Additionally, the Routing Context parameter identifies the SS7 2653 network context for the message, for the purposes of logically 2654 separating the signalling traffic between the SGP and the 2655 Application Server Process over a common SCTP Association, when 2656 needed. An example is where an SGP is logically partitioned to 2657 appear as an element in several different national SS7 networks. It 2658 implicitly defines the SS7 Point Code format used, the SS7 Network 2659 Indicator value and SCCP protocol type/variant/version used within a 2660 separate SS7 network. It also defines the network context for the PC 2661 and SSN values. Where an SGP operates in the context of a single SS7 2662 network, or individual SCTP associations are dedicated to each SS7 2663 network context, this functionality is not needed. 2665 If the Routing Context parameter is present, it SHOULD be the first 2666 parameter in the message as it defines the format and/or 2667 interpretation of the parameters containing a PC or SSN value. 2669 3.9.7 Diagnostic Information 2671 The Diagnostic Information can be used to convey any information 2672 relevant to an error condition, to assist in the identification of 2673 the error condition. In the case of an Adaptation Layer Identifier 2674 or Traffic Handling Mode, the Diagnostic Information includes the 2675 received parameter. In the other cases, the Diagnostic information 2676 may be the first 40 bytes of the offending message. 2678 0 1 2 3 2679 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2680 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2681 | Tag = 0x0007 | Length | 2682 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2683 / Diagnostic Information / 2684 \ \ 2685 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2687 3.9.8 Not Used 2689 Parameter ID 0x0008 is not used in SUA. 2691 3.9.9 Heartbeat Data 2693 The sending node defines the Heartbeat Data field contents. It may 2694 include a Heartbeat Sequence Number and/or Timestamp, or other 2695 implementation specific details. 2697 The receiver of a Heartbeat message does not process this field as 2698 it is only of significance to the sender. The receiver echoes the 2699 content of the Heartbeat Data in a BEAT-Ack message. 2701 0 1 2 3 2702 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2703 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2704 | Tag = 0x0009 | Length | 2705 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2706 / Heartbeat Data / 2707 \ \ 2708 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2710 The data field can be used to store information in the heartbeat 2711 message useful to the sending node (e.g. the data field can contain 2712 a time stamp, a sequence number, etc.). 2714 3.9.10 Not Used 2716 Parameter ID 0x000A is not used in SUA. 2718 3.9.11 Traffic Mode Type 2720 The Traffic Mode Type parameter identifies the traffic mode of 2721 operation of the ASP within an AS. 2723 0 1 2 3 2724 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2725 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2726 | Tag = 0x000B | Length = 8 | 2727 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2728 | Traffic Mode Type | 2729 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2731 The valid values for Type are shown in the following table. 2733 1 Over-ride 2734 2 Load-share 2735 3 Broadcast 2737 Within a Routing Context, Over-ride, Loadshare Types and Broadcast 2738 cannot be mixed. The Over-ride value indicates that the ASP is 2739 operating in Over-ride mode, and the ASP wishes to take over all 2740 traffic for an Application Server (i.e., primary/back-up operation), 2741 over-riding any currently active ASP in the AS. In Load-share mode, 2742 the ASP wishes to share in the traffic distribution with any other 2743 currently active ASPs. In Broadcast mode, the ASP wishes to receive 2744 the same traffic as any other currently active APSs. When there are 2745 insufficient ASPs, the sender may immediately move the ASP to 2746 Active. 2748 3.9.12 Error Code 2750 0 1 2 3 2751 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2752 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2753 | Tag =0x000C | Length = 8 | 2754 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2755 | Error Code | 2756 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2758 The Error Code parameter indicates the reason for the Error Message. 2759 The Error parameter value can be one of the following values: 2761 0x01 Invalid Version 2762 0x02 Not Used in SUA 2763 0x03 Unsupported Message Class 2764 0x04 Unsupported Message Type 2765 0x05 Unsupported Traffic Handling Mode 2766 0x06 Unexpected Message 2767 0x07 Protocol Error 2768 0x08 Not used in SUA 2769 0x09 Invalid Stream Identifier 2770 0x0a Not used in SUA 2771 0x0b Not used in SUA 2772 0x0c Not used in SUA 2773 0x0d Refused - Management Blocking 2774 0x0e ASP Identifier Required 2775 0x0f Invalid ASP Identifier 2776 0x10 Not Used in SUA 2777 0x11 Invalid Parameter Value 2778 0x12 Parameter Field Error 2779 0x13 Unexpected Parameter 2780 0x14 Destination Status Unknown 2781 0x15 Invalid Network Appearance 2782 0x16 Missing Parameter 2783 0x17 Not Used in SUA 2784 0x18 Not Used in SUA 2785 0x19 Invalid Routing Context 2786 0x1a No Configured AS for ASP 2787 0x1b Subsystem Status Unknown 2788 0x1c Invalid loadsharing label 2790 The "Invalid Version" error is sent if a message was received with 2791 an invalid or unsupported version. The Error message contains the 2792 supported version in the Common header. The Error message could 2793 optionally provide the supported version in the Diagnostic 2794 information area. 2796 The "Unsupported Message Class" error is sent if a message with an 2797 unexpected or unsupported Message Class is received. 2799 The "Unsupported Message Type" error is sent if a message with an 2800 unexpected or unsupported Message Type is received. 2802 The "Unsupported Traffic Handling Mode" error is sent by a SGP if an 2803 ASP sends an ASP Active message with an unsupported Traffic Mode 2804 Type or a Traffic Mode Type that is inconsistent with the presently 2805 configured mode for the Application Server. An example would be a 2806 case in which the SGP did not support loadsharing. 2808 The "Unexpected Message" error MAY be sent if a defined and 2809 recognized message is received that is not expected in the current 2810 state (in some cases the ASP may optionally silently discard the 2811 message and not send an Error message). For example, silent discard 2812 is used by an ASP if it received a DATA message from an SGP while it 2813 was in the ASP-INACTIVE state. If the Unexpected message contained 2814 Routing Context(s), the Routing Context(s) SHOULD be included in the 2815 Error message. 2817 The "Protocol Error" error is sent for any protocol anomaly (i.e., 2818 reception of a parameter that is syntactically correct but 2819 unexpected in the current situation. 2821 The "Invalid Stream Identifier" error is sent if a message is 2822 received on an unexpected SCTP stream. 2824 The "Refused - Management Blocking" error is sent when an ASP Up or 2825 ASP Active message is received and the request is refused for 2826 management reasons (e.g., management lockout"). If this error is in 2827 response to an ASP Active message, the Routing Context(s) in the ASP 2828 Active message SHOULD be included in the Error message. 2830 The "ASP Identifier Required" is sent by a SGP in response to an ASP 2831 Up message that does not contain an ASP Identifier parameter when 2832 the SGP requires one. The ASP SHOULD resend the ASP Up message with 2833 an ASP Identifier. 2835 The "Invalid ASP Identifier" is send by a SGP in response to an ASP 2836 Up message with an invalid (i.e., non-unique) ASP Identifier. 2838 The "Invalid Parameter Value " error is sent if a message is 2839 received with an invalid parameter value (e.g., a DUPU message was 2840 received with a Mask value other than "0". 2842 The "Parameter Field Error" would be sent if a message is received 2843 with a parameter having a wrong length field. 2845 The "Unexpected Parameter" error would be sent if a message contains 2846 an invalid parameter. 2848 The "Destination Status Unknown" Error MAY be sent if a DAUD is 2849 received at an SG enquiring of the availability/congestion status of 2850 a destination, and the SG does not wish to provide the status (e.g., 2851 the sender is not authorized to know the status). For this error, 2852 the invalid or unauthorized Point Code(s) MUST be included along 2853 with the Network Appearance and/or Routing Context associated with 2854 the Point Code(s). 2856 The "Invalid Network Appearance" error is sent by a SGP if an ASP 2857 sends a message with an invalid (unconfigured) Network Appearance 2858 value. For this error, the invalid (unconfigured) Network Appearance 2859 MUST be included in the Network Appearance parameter. 2861 The "Missing Parameter" error would be sent if a mandatory parameter 2862 were not included in a message. 2864 The "Invalid Routing Context" error would be sent by a SG if an ASP 2865 sends a message with an invalid (unconfigured) Routing Context 2866 value. The Error message could optionally provide the invalid 2867 Routing Context in the Diagnostic Information area. 2869 The "No Configured AS for ASP" error is sent if a message is 2870 received from a peer without a Routing Context parameter and it is 2871 not known by configuration data, which Application Servers are 2872 referenced. 2874 The "Destination Status Unknown" Error MAY be sent if a DAUD is 2875 received at an SG enquiring of the availability or congestion status 2876 of a destination, and the SG does not wish to provide the status 2877 (e.g., the sender is not authorized to know the status). For this 2878 error, the invalid or unauthorized Point Code(s) MUST be included 2879 along with the Network Appearance and Routing Context associated 2880 with the Point Code(s). 2882 The "Subsystem Status Unknown" Error MAY be sent if a DAUD is 2883 received at an SG enquiring of the availability or congestion status 2884 of a subsystem, and the SG does not wish to provide the status 2885 (e.g., the sender is not authorized to know the status). For this 2886 error, the invalid or unauthorized Point Code and Subsytstem Number 2887 MUST be included along with the Network Appearance and Routing 2888 Context associated with the Point Code and Subsystem Number. 2890 3.9.13 Status 2891 The Status parameter identifies the type of the status that is being 2892 notified and the Status ID. 2894 0 1 2 3 2895 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2896 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2897 | Tag = 0x000D | Length = 8 | 2898 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2899 | Status Type | Status ID | 2900 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2902 The valid values for Status Type (16 bit unsigned integer) are: 2904 1 Application Server state change (AS_State_Change) 2905 2 Other 2907 The Status ID parameter contains more detailed information for the 2908 notification, based on the value of the Status Type. 2910 If the Status Type is AS_STATE_CHANGE, then the Status ID (16 bit 2911 unsigned integer) values are: 2913 1 reserved 2914 2 Application Server Inactive (AS-Inactive) 2915 3 Application Server Active (AS-Active) 2916 4 Application Server Pending (AS-Pending) 2918 These notifications are sent from an SGP to an ASP upon a change in 2919 status of a particular Application Server. The value reflects the 2920 new state of the Application Server. 2922 If the Status Type is "Other", then the following Status Information 2923 values are defined: 2925 1 Insufficient ASP resources active in AS 2926 2 Alternate ASP Active 2927 3 ASP failure 2929 These notifications are not based on the SGP reporting the state 2930 change of an ASP or AS. In the Insufficient ASP Resources case, the 2931 SGP is indicating to an "Inactive" ASP(s) in the AS that another ASP 2932 is required to handle the load of the AS (Load-sharing mode or 2933 Broadcast mode). For the Alternate ASP Active case, an ASP is 2934 informed when an alternate ASP transitions to the ASP-Active state 2935 in Over-ride mode. 2937 3.9.14 Not Used in SUA 2939 Parameter ID 0x000E is not used in SUA. 2941 3.9.15 Not Used in SUA 2943 Parameter ID 0x000F is not used in SUA. 2945 3.9.16 Not Used in SUA 2947 Parameter ID 0x0010 is not used in SUA. 2949 3.9.17 ASP Identifier 2951 0 1 2 3 2952 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2953 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2954 | Tag = 0x0011 | Length = 8 | 2955 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2956 | ASP Identifier | 2957 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2959 ASP Identifier field: 32-bits (unsigned integer) 2961 The ASP Identifier field contains a unique value that is locally 2962 significant amoung the ASPs that support an AS. The SGP should save 2963 the ASP Identifier to be used, if necessary, with the Notify message 2964 (see Section 3.7.2). 2966 3.9.18 Affected Point Code 2968 The Affected Point Code Destinations parameter contains a list of 2969 Affected Point Code fields, each a three-octet parameter to allow 2970 for 14-, 16- and 24-bit binary formatted SS7 Point Codes. Affected 2971 Point Codes that are less than 24-bits are padded on the left to the 2972 24-bit boundary. 2974 0 1 2 3 2975 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2976 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2977 | Tag = 0x0012 | Length | 2978 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2979 | Mask | Affected PC 1 | 2980 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2981 / . . . / 2982 \ \ 2983 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2985 The encoding is shown below for ANSI and ITU Point Code examples. 2987 ANSI 24-bit Point Code: 2989 0 1 2 3--> 2990 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2991 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2992 | Mask | Network | Cluster | Member | 2993 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2994 |MSB-----------------------------------------LSB| 2996 ITU 14-bit Point Code: 2998 0 1 2 3--> 2999 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3000 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3001 | Mask |0 0 0 0 0 0 0 0 0 0|Zone | Region | SP | 3002 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3003 |MSB--------------------LSB| 3005 It is OPTIONAL for an implementation to generate an Affected Point 3006 Code parameter with more than on Affected PC but the implementation 3007 MUST accept and process an Affected Point Code parameter with more 3008 than one Affected PC. 3010 Mask: 8-bits 3012 The Mask parameter can be used to identify a contiguous range of 3013 Affected Destination Point Codes, independent of the point code 3014 format. Identifying a contiguous range of Affected PCs may be 3015 useful when reception of an MTP3 management message or a linkset 3016 event simultaneously affects the availability status of a series of 3017 destinations at an SG. 3019 The Mask parameter is an integer representing a bit mask that can be 3020 applied to the related Affected PC field. The bit mask identifies 3021 how many bits of the Affected PC field are significant and which are 3022 effectively "wild-carded". For example, a mask of "8" indicates 3023 that the last eight bits of the PC is "wild-carded". For an ANSI 3024 24-bit Affected PC, this is equivalent to signalling that all PCs in 3025 an ANSI Cluster are unavailable. A mask of "3" indicates that the 3026 last three bits of the PC is "wild-carded". For a 14-bit ITU 3027 Affected PC, this is equivalent to signalling that an ITU Region is 3028 unavailable. 3030 3.9.19 Correlation ID 3032 0 1 2 3 3033 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3034 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3035 | Tag = 0x0013 | Length = 8 | 3036 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3037 | Correlation ID | 3038 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3040 The Correlation ID is a 32-bit identifier that is attached to CLDT 3041 messages to indicate to a newly entering ASP in a Broadcast AS where 3042 in the traffic flow of CLDT messages the ASP is joining. It is 3043 attached to the first CLDT message sent to an ASP by an SG after 3044 sending an ASP Active Ack or otherwise starting traffic to an ASP. 3045 The Correlation ID is only significant within a Routing Context. 3047 Implementation note: Correlation ID parameter can be use for 3048 features like Synchronisation of ASPs/SGPs in a Broadcast Mode 3049 AS/SG; avoid message duplication and mis-sequencing in case of 3050 failover of association from one ASP/SGP to other ASP/SGP etc. 3052 3.9.20 Registration Result 3054 0 1 2 3 3055 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3056 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3057 | Tag = 0x0018 | Length | 3058 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3059 | Routing Key Identifier | 3060 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3061 | Tag = 0x0016 | Length | 3062 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3063 | Registration Status | 3064 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3065 | Tag = 0x0006 | Length | 3066 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3067 | Routing Context | 3068 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3070 Routing Key Identifier contains the same TLV formatted paramter 3071 value as found in the matching Routing Key parameter in the REG REQ 3072 message. 3074 Routing Context contains the same TLV formatted Routing Context 3075 parameter for the associated Routing Key if the registration was 3076 successful. It is set to "0" if the registration was not 3077 successful. 3079 3.9.21 Deregistration Result 3081 0 1 2 3 3082 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3083 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3084 | Tag = 0x0006 | Length | 3085 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3086 | Routing Context | 3087 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3088 | Tag = 0x0017 | Length | 3089 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3090 | Deregistration Status | 3091 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3093 Routing Context: 32-bit integer 3095 Routing Context contains the Routing Context value of the matching 3096 Routing key to deregister, as found in the DEREG REQ message. 3098 Deregistration Status: 32-bit integer 3100 Deregistration Status parameter indicates the success or the 3101 reason for failure of the deregistration. 3103 3.9.22 Registration Status 3105 0 1 2 3 3106 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3107 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3108 | Tag = 0x0016 | Length = 8 | 3109 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3110 | Registration Status | 3111 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3113 Registration Status: 32-bits (unsigned integer) 3115 The Registration Status field indicates the success or the reason 3116 for failure of a registration request. 3118 Its values may be: 3119 0 Successfully Registered 3120 1 Error - Unknown 3121 2 Error - Invalid Destination Address 3122 3 Error - Invalid Network Appearance 3123 4 Error - Invalid Routing Key 3124 5 Error - Permission Denied 3125 6 Error - Cannot Support Unique Routing 3126 7 Error - Routing Key not Currently Provisioned 3127 8 Error - Insufficient Resources 3128 9 Error - Unsupported RK parameter Field 3129 10 Error - Unsupported/Invalid Traffic Mode Type 3130 11 Error - Routing Key Change Refused 3132 3.9.23 Deregistration Status 3134 0 1 2 3 3135 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3136 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3137 | Tag = 0x0017 | Length = 8 | 3138 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3139 | Deregistration Status | 3140 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3142 Deregistration Status: 32-bit integer 3143 The Deregistration Result Status field indicates the success or 3144 the reason for failure of the deregistration. 3146 Its values may be: 3147 0 Successfully Deregistered 3148 1 Error - Unknown 3149 2 Error - Invalid Routing Context 3150 3 Error - Permission Denied 3151 4 Error - Not Registered 3152 5 Error - ASP Currently Active for Routing Context 3154 3.9.24 Local Routing Key Identifier 3156 0 1 2 3 3157 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3158 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3159 | Tag = 0x0018 | Length = 8 | 3160 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3161 | Local Routing Key Identifier | 3162 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3164 The Local Routing Key Identifier field is a 32-bits unsigned 3165 integer. The Identifier value is assigned by the ASP and is used to 3166 correlate the response in a REG RSP message with the original 3167 registration request. The Identifier value must remain unique until 3168 the REG RSP message is received. 3170 3.10 SUA-Specific parameters 3172 These TLV parameters are specific to the SUA protocol. 3174 Parameter Name Parameter ID 3175 ============== ============ 3176 SS7 Hop Counter 0x0101 3177 Source Address 0x0102 3178 Destination Address 0x0103 3179 Source Reference Number 0x0104 3180 Destination Reference Number 0x0105 3181 SCCP Cause 0x0106 3182 Sequence Number 0x0107 3183 Receive Sequence Number 0x0108 3184 ASP Capabilities 0x0109 3185 Credit 0x010A 3186 Data 0x010B 3187 User/Cause 0x010C 3188 Network Appearance 0x010D 3189 Routing Key 0x010E 3190 DRN Label 0x010F 3191 TID Label 0x0110 3192 Address Range 0x0111 3193 SMI 0x0112 3194 Importance 0x0113 3195 Message Priority 0x0114 3196 Protocol Class 0x0115 3197 Sequence Control 0x0116 3198 Segmentation 0x0117 3199 Congestion Level 0x0118 3201 Destination/Source Address Sub-Parameters 3202 =========================================== 3203 Global Title 0x8001 3204 Point Code 0x8002 3205 Subsystem Number 0x8003 3206 IPv4 Address 0x8004 3207 Hostname 0x8005 3208 IPv6 Addresses 0x8006 3210 3.10.1 SS7 Hop counter 3212 0 1 2 3 3213 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3214 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3215 | Tag = 0x0101 | Length = 8 | 3216 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3217 | Reserved | SS7 Hop Count | 3218 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3220 SS7 Hop Counter (3.18/Q.713) 3222 The value of the SS7 Hop Counter is decremented with each global 3223 title translation and is in the range 15 to 1. 3225 3.10.2 Source Address 3227 0 1 2 3 3228 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3229 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3230 | Tag = 0x0102 | Parameter Length | 3231 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3232 | Routing Indicator | Address Indicator | 3233 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3234 / Address parameter(s) / 3235 \ \ 3236 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3238 The following combinations of address parameters are valid: 3240 - Global Title (e.g. E.164 number) + optional PC and/or SSN, 3241 SSN may be zero, when routing is done on Global Title 3242 - SSN (non-zero) + optional PC and/or Global Title, when 3243 routing is done on PC + SSN. The PC is mandatory in the 3244 source address when sending from SGP to ASP, and in the 3245 destination address when sending from ASP to SGP to reach the 3246 SS7 SEP. 3248 - Hostname + optional SSN, when routing is done by Hostname 3249 - SSN (non-zero) and optional IP address (IPv4 or IPv6) when 3250 routing is done on IP address + SSN 3252 3.10.2.1 Routing Indicator 3254 The following values are valid for the routing indicator: 3256 Reserved 0 3257 Route on Global Title 1 3258 Route on SSN + PC 2 3259 Route on Hostname 3 3260 Route on SSN + IP Address 4 3262 The routing indicator determines which address parameters need to be 3263 present in the address parameters field. 3265 3.10.2.2 Address Indicator 3267 This parameter is needed for interworking with SS7 networks. The 3268 address indicator specifies what address parameters are actually 3269 received in the SCCP address from the SS7 network, or are to be 3270 populated in the SCCP address when the message is sent into the SS7 3271 network. The value of the routing indicator needs to be taken into 3272 account. It is used in the ASP to SG direction. For example, the 3273 PC parameter is present in the destination address of the CLDT sent 3274 from ASP->SG, but bit 2 is set to "0" meaning "do not populate this 3275 in the SCCP called party address". The effect is that the SG only 3276 uses the PC to populate the MTP routing label DPC field, but does 3277 not include it in the SCCP called party address. 3279 In the SG->ASP direction, the source address PC parameter is present 3280 (PC of SS7 SEP). However, this may have been populated from the OPC 3281 in the received MTP routing label, not from the PC field in the SCCP 3282 calling party address. In this case, bit 2 = "0" denotes that. The 3283 AI gives further instructions to the SG how and when to populate the 3284 SCCP addresses; in the SG->ASP direction, the AI gives information 3285 to the ASP as to what was actually present in the received SCCP 3286 addresses. 3288 The address indicator is coded as follows: 3290 Bit 1 is used to indicate inclusion of the SSN 3292 0 Do not include SSN when optional 3293 1 Include SSN 3295 Bit 2 is used to indicate inclusion of the PC 3297 0 Do not include PC, regardless of the routing indicator 3298 value 3300 1 Include PC 3302 Bit 3 is used to indicate inclusion of the Global Title 3304 0 Do not include GT when optional (routing indicator /= 1) 3305 1 Include GT 3307 The remaining bits are spare and SHOULD be coded zero, and MUST be 3308 ignored by the receiver. 3310 3.10.2.3 Global Title 3312 0 1 2 3 3313 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3314 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3315 | Tag = 0x8001 | Length | 3316 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3317 | Reserved | GTI | 3318 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3319 | No. Digits | Trans. type | Num. Plan | Nature of Add | 3320 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3321 / Global Title Digits / 3322 \ \ 3323 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3325 Number of Digits: 3327 This is the number of digits contained in the Global Title. 3329 GTI (defined in chapter 3.4.2.3 of Q.713): 3331 0000 Reserverd 3332 0001 Nature of Address is ignored. Translation Type = Unknown 3333 and Numbering Plan = E.164 (value 1). 3334 0010 This is most commonly used in North American networks. 3335 The Translation Type implicitly determines Nature of 3336 Address and Numbering Plan. This data can be configured 3337 in the SG. The number of digits is always even and 3338 determined by the SCCP address length. 3339 0011 Numbering Plan and Translation Type are taken over. It is 3340 implicitly assumed that the Nature of Address = Unknown. 3341 0100 This format is used in international networks and most 3342 commonly in networks outside North America. All 3343 information to populate the source address is present in 3344 the SCCP Address. 3346 Translation type: 3348 0 Unknown 3349 1 - 63 International services 3350 64 - 127 Spare 3351 128 - 254 National network specific 3352 255 Reserved 3354 Numbering Plan: 3356 0 unknown 3357 1 ISDN/telephony numbering plan (Recommendations E.163 and 3358 E.164) 3359 2 generic numbering plan 3360 3 data numbering plan (Recommendation X.121) 3361 4 telex numbering plan (Recommendation F.69) 3362 5 maritime mobile numbering plan (Recommendations E.210, 3363 E.211) 3364 6 land mobile numbering plan (Recommendation E.212) 3365 7 ISDN/mobile numbering plan (Recommendation E.214) 3366 8 - 13 spare 3367 14 private network or network-specific numbering plan 3368 15 - 126 spare 3369 127 reserved. 3371 Nature of Address: 3373 0 unknown 3374 1 subscriber number 3375 2 reserved for national use 3376 3 national significant number 3377 4 international number 3378 5 - 255 Spare 3380 Global Title: 3382 Octets contain a number of address signals and possibly filler as 3383 shown: 3385 0 1 2 3 3386 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3387 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3388 |2 addr.|1 addr.|4 addr.|3 addr.|6 addr.|5 addr.|8 addr.|7 addr.| 3389 | sig. | sig. | sig. | sig. | sig. | sig. | sig. | sig. | 3390 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3391 | ............. |filler |N addr.| filler | 3392 | |if req | sig. | | 3393 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3395 All filler bits SHOULD be set to 0. 3397 Address signals to be coded as defined in ITU-T Q.713 Section 3398 3.4.2.3.1. 3400 3.10.2.4 Point Code 3402 0 1 2 3 3403 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3404 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3405 | Tag = 0x8002 | Length = 8 | 3406 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3407 | Point Code | 3408 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3410 See chapter 3.9.18 Affected Point Code for the layout of the Point 3411 Code field. 3413 3.10.2.5 Subsystem Number 3415 0 1 2 3 3416 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3417 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3418 | Tag = 0x8003 | Length = 8 | 3419 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3420 | Reserved | SSN value | 3421 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3423 The internationally standardized SSN values are described in chapter 3424 3.4.2.2 of Q.713. 3426 3.10.2.6 IP Addresses 3428 The IP address formats can use different tags. It should be noted 3429 that if the source address is in a certain IP version, the 3430 destination address should also be in the same IP version. 3432 0 1 2 3 3433 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3434 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3435 | Tag = 0x8004/0x8006 | Length | 3436 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3437 / IPv4 or IPv6 Address / 3438 \ \ 3439 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3441 Note: The tag value 0x8004 is for an IPv4 address and 0x8006 is for 3442 IPv6. 3444 3.10.2.7 Hostname 3446 0 1 2 3 3447 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3448 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3449 | Tag = 0x8005 | Length | 3450 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3451 / Host Name / 3452 \ \ 3453 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3455 Host Name: variable length 3457 This field contains a host name in "host name syntax" per RFC 1123 3458 Section 2.1 [1123]. The method for resolving the host name is 3459 out of scope for this document. 3461 Note: At least one null terminator is included in the Host Name 3462 string and must be included in the length. 3464 3.10.3 Destination Address 3466 0 1 2 3 3467 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3468 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3469 | Tag = 0x0103 | Parameter Length | 3470 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3471 | Routing Indicator | Address Indicator | 3472 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3473 / Address Parameter(s) / 3474 \ \ 3475 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3477 The format of this parameter is identical to the Source Address 3478 parameter. 3480 3.10.4 Source Reference Number 3482 0 1 2 3 3483 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3484 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3485 | Tag = 0x0104 | Length = 8 | 3486 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3487 | Source Reference Number | 3488 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3490 The source reference number is a 4 octet long integer. This is 3491 allocated by the source SUA instance. 3493 3.10.5 Destination Reference Number 3494 0 1 2 3 3495 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3496 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3497 | Tag = 0x0105 | Length = 8 | 3498 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3499 | Destination Reference Number | 3500 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3502 The destination reference number is a 4 octet long integer. This is 3503 allocated by the destination SUA instance. 3505 3.10.6 SCCP Cause 3507 0 1 2 3 3508 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3509 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3510 | Tag = 0x0106 | Length = 8 | 3511 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3512 | Reserved | Cause Type | Cause Value | 3513 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3515 This parameter bundles the SCCP parameters Release cause, Return 3516 cause, Reset cause, Error cause and Refusal cause. 3518 Cause Type can have the following values: 3520 Return Cause 0x1 3521 Refusal Cause 0x2 3522 Release Cause 0x3 3523 Reset Cause 0x4 3524 Error Cause 0x5 3526 Cause Value contains the specific cause value. Below gives examples 3527 for ITU SCCP values. ANSI references can be found in ANSI T1.112.3 3529 Cause value in Correspondence with Reference 3530 SUA message SCCP parameter 3531 ------------------ ----------------- --------- 3532 CLDR Return Cause ITU-T Q.713 Chap 3.12 3533 COREF Refusal Cause ITU-T Q.713 Chap 3.15 3534 RELRE Release Cause ITU-T Q.713 Chap 3.11 3535 RESRE Reset Cause ITU-T Q.713 Chap 3.13 3536 ERR Error Cause ITU-T Q.713 Chap 3.14 3538 3.10.7 Sequence Number 3539 0 1 2 3 3540 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3541 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3542 | Tag = 0x0107 | Length = 8 | 3543 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3544 | Reserved | Rec Seq Num|M| Sent Seq Num | 3545 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3547 This parameter is used to indicate whether "more" data will follow 3548 in subsequent CODT messages, and/or to number each CODT message 3549 sequentially for the purpose of flow control. It contains the 3550 received as well as the sent sequence number, P(R) and P(S) in 3551 Q.713, chapters 3.7 and 3.9. 3553 As such it can also be used to acknowledge the receipt of data 3554 transfers from the peer in case of protocol class 3. 3556 Sent Sequence Number is one octet and is coded as follows: 3558 Bits 2-8 are used to indicate the Send Sequence Number P(S). 3559 Bit 1 (LSB) of octet 1 is spare. 3561 Received Sequence Number is one octet, and is coded as follows: 3563 Bits 2-8 are used to indicate the Received Sequence Number 3564 P(R). 3565 Bit 1 (LSB) is used for the more data indication, as follows: 3567 0 no more data 3568 1 more data 3570 3.10.8 Receive Sequence Number 3572 0 1 2 3 3573 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3574 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3575 | Tag = 0x0108 | Length = 8 | 3576 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3577 | Reserved | Rec Seq Num | 3578 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3580 This parameter is used exclusively for protocol class 3 in the data 3581 acknowledgment message to indicate the lower edge of the receiving 3582 window. See Q.713, chapter 3.9. 3584 It is a 1 octet long integer coded as follows: 3586 Bits 8-2 are used to indicate the Receive Sequence Number P(R). 3588 Bit 1 is spare. 3590 3.10.9 ASP Capabilities 3592 This parameter is used so that the ASP can report its capabilities 3593 regarding SUA for supporting different protocol classes and 3594 interworking scenarios. 3596 0 1 2 3 3597 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3598 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3599 | Tag = 0x0109 | Length = 8 | 3600 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3601 | Reserved |0 0 0 0|a|b|c|d| Interworking | 3602 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3604 Flags 3606 a - Protocol Class 3 3607 b - Protocol Class 2 3608 c - Protocol Class 1 3609 d - Protocol Class 0 3611 It is mandatory to support at least Protocol Class 0. 3613 Interworking 3615 Values 3617 0x0 indicates no interworking with SS7 Networks. 3618 0x1 indicates IP Signalling Endpoint (ASP), interworking with SS7 3619 networks. 3620 0x2 indicates Signalling Gateway. 3621 0x3 indicates relay node support. 3623 3.10.10 Credit 3625 0 1 2 3 3626 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3627 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3628 | Tag = 0x010A | Length = 8 | 3629 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3630 | Reserverd | Credit | 3631 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3633 The length of the credit field is is one octet. See ITU-T Q.713 3634 Chapter 3.10. The parameter is used for protocol class 3 3635 exclusively. 3637 3.10.11 Data 3638 0 1 2 3 3639 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3640 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3641 | Tag = 0x010b | Length | 3642 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3643 / Data / 3644 \ \ 3645 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3647 The Data parameter field contains the SS7 SCCP-User application 3648 message, for example an INAP/TCAP message. 3650 3.10.12 User/Cause 3652 0 1 2 3 3653 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3654 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3655 | Tag = 0x010c | Length = 8 | 3656 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3657 | Cause | User | 3658 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3660 "User" is coded to that SCCP's SI value. There may be several 3661 SCCP's at a given point code, each with different SI values, 3662 although normally there is only one with SI = 3. 3664 Cause may take the following values 3666 0 remote SCCP unavailable, reason unknown; 3667 1 remote SCCP unequipped; 3668 2 remote SCCP inaccessible; 3670 3.10.13 Network Appearance 3672 0 1 2 3 3673 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3674 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3675 | Tag = 0x010D | Length = 8 | 3676 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3677 | Network Appearance | 3678 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3680 Network Appearance field: 32-bits (unsigned integer) 3682 The Network Appearance field identifies the SS7 network context 3683 for the Routing Key. The Network Appearance value is of local 3684 significance only, coordinated between the SG and ASP. Therefore, 3685 in the case where the ASP is connected to more than one SG, the 3686 same SS7 Network context may be identified by different Network 3687 Appearance values depending upon to which SG the ASP is 3688 registering. 3690 In the Routing Key, the Network Appearance identifies the SS7 3691 Point Code and Global Title Translation Type format used, and the 3692 SCCP and possibly the SCCP-User protocol (type, variant and 3693 version) used within the specific SS7 network. 3695 3.10.14 Routing Key 3697 0 1 2 3 3698 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3699 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3700 | Tag = 0x010E | Length | 3701 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3702 | Tag = 0x0018 | Length = 8 | 3703 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3704 | Local Routing Key Identifier | 3705 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3706 \ Key parameter(s) \ 3707 / / 3708 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3710 Local Routing Key Identifier field: 32-bits (unsigned integer) 3712 Key field: variable 3714 The Key field contains the following parameters: 3716 Parameter 3717 Traffic Mode Type Optional 3718 Network Appearance Optional *1 3719 Source Address Optional 3720 Destination Address Optional 3721 Address Range Optional 3723 Note 1: The Network Appearance parameter must be included in the 3724 Routing Key when the ASP is able to register in 3726 multiple SS7 Network contexts. 3728 3.10.15 DRN Label 3730 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3731 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3732 | Tag = 0x010F | Length = 8 | 3733 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3734 | start | end | label value | 3735 +---------------+---------------+-------------------------------+ 3737 The Start parameter is the start position of label, between 0 (LSB) 3738 and 23 (MSB). 3740 The End parameter is the end position of label, between 0 (LSB) and 3741 23 (MSB). 3743 Label value is a 16-bit interger, which is unique across an AS. 3745 3.10.16 TID Label 3747 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3748 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3749 | Tag = 0x0110 | Length = 8 | 3750 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3751 | start | end | label value | 3752 +---------------+---------------+-------------------------------+ 3754 The Start parameter is the start position of label, between 0 (LSB) 3755 and 31 (MSB). 3757 The End parameter is the end position of label, between 0 (LSB) and 3758 31 (MSB). 3760 Label value is a 16-bit interger, which is unique across an AS. 3762 3.10.17 Address Range 3764 0 1 2 3 3765 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3766 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3767 | Tag = 0x0111 | Length | 3768 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3769 \ Address parameter(s) \ 3770 / / 3771 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3773 Address field: 3775 The Address field the following parameters: 3777 Parameter 3778 Source Address Optional *1 3779 Destination Address Optional *1 3781 Note 1: The Address field must contain pairs of Source Addresses or 3782 pairs of Destination Addresses but MUST NOT mix Source 3783 Addresses with Destination Addresses in the same Address 3784 field. 3786 3.10.18 SMI 3788 0 1 2 3 3789 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3790 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3791 | Tag = 0x0112 | Length = 8 | 3792 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3793 | Reserved | SMI | 3794 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3796 Subsystem Multiplicity Indicator (SMI) can have the following 3797 values: 3799 0x00 Reserved/Unknown 3800 0x01 Solitary 3801 0x02 Duplicated 3802 0x03 Triplicated 3803 0x04 Quadruplicated 3804 ... ... 3805 0xff Unspecified 3807 3.10.19 Importance 3809 0 1 2 3 3810 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3811 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3812 | Tag = 0x0113 | Length = 8 | 3813 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3814 | Reserved | Importance | 3815 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3817 Importance (3.19/Q.713) 3819 Possible values of the Importance Parameter are between 0 and 7, 3820 where the value of 0 indicates the least important and 7 indicates 3821 the most important. 3823 3.10.20 Message Priority (or Priority) 3825 0 1 2 3 3826 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3827 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3828 | Tag = 0x0114 | Length = 8 | 3829 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3830 | Reserved | Msg Priority | 3831 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3833 Priority 3835 Priority value ranges from 0 to 3. If the Priority value has not 3836 been specified by the SCCP user, it should be set to 0xFF. The SG 3837 MAY take the priority into account for determining the MTP message 3838 priority. In the all-IP case, this parameter MAY be used. 3840 The Message Priority parameter is optional in the CLDT, CLDR, CORE, 3841 COAK and CODT messages. However, for networks, which support 3842 Message Priority message priorities (e.g, ANSI), this parameter MUST 3843 be included but it is not required for those which don't (e.g., 3844 International). 3846 3.10.21 Protocol Class 3848 0 1 2 3 3849 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3850 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3851 | Tag = 0x0115 | Length = 8 | 3852 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3853 | Reserved | Protocol Cl. | 3854 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3856 Protocol class (3.6/Q.713) 3858 Bits 1-2 indicate the protocol class. 3860 Value Description 3861 0 Class 0 (connectionless service) 3862 1 Class 1 (connectionless service) 3863 2 Class 2 (connection-oriented service) 3864 3 Class 3 (connection-oriented service) 3866 Bit 8 indicates the use of the return on error procedure. 3868 Value Description 3869 0x0 No special options 3870 0x1 Return message on error 3872 Bits 3-7 are spare and SHOULD be coded zero, and MUST be 3873 ignored by the receiver. 3875 3.10.22 Sequence Control 3877 0 1 2 3 3878 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3879 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3880 | Tag = 0x0116 | Length = 8 | 3881 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3882 | Sequence Control | 3883 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3885 Sequence Control (6.2.2.2.2/Q.711) 3887 The field is coded with the value of the sequence control parameter 3888 associated with a group of messages and are chosen so as to ensure 3889 proper loadsharing of message groups over SLS values while ensuring 3890 that sequence control values within message groups have the sequence 3891 control value coded with the same value as the initial message of 3892 the message group. 3894 3.10.23 Segmentation 3896 0 1 2 3 3897 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3898 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3899 | Tag = 0x0117 | Length = 32 | 3900 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3901 | first/remain | Segmentation Reference | 3902 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3904 The first/remaining segments field is formatted as follows: 3905 bit 8 (MSB) : indicates whether this is the first segment (1) or not 3906 (0) 3908 bits 1-7: indicate the number of remaining segments, value between 0 3909 and 15 3911 The field would thus be coded 1000 0000 (first, no remaining 3912 segments) for a non-segmented CLDT. 3914 The segmentation reference field is a 3 byte integer, assigned by 3915 the ASP. 3917 3.10.24 Congestion Level 3919 0 1 2 3 3920 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 3921 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3922 | Tag = 0x0118 | Length = 8 | 3923 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3924 | Congestion Level | 3925 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 3927 Congestion Level field: 8-bits (unsigned integer) 3929 The Congestion Level field contains the level at which congestion 3930 has occured. 3932 When the Congestion Level parameter is included in a SCON message 3933 that corresponds to an N-PCSTATE primitive, the Congestion Level 3934 field indicates the MTP congestion level experienced by the local or 3935 affected signalling point as indicated by the Affected Point Code(s) 3936 also in the SCON message. In this case, valid values for the 3937 Congestion Level field are as follows: 3939 0 No Congestion or Undefined 3940 1 Congestion Level 1 3941 2 Congestion Level 2 3942 3 Congestion Level 3 3944 When the Congestion Level parameter is included in a SCON 3945 messagethat corresponds to an N-STATE primitive, the Congestion 3946 Level field indicates the SCCP restricted importance level 3947 experienced by the local or affected subsystem as indicated by the 3948 Affected Point Code and Subsystem Number also in the SCON message. 3949 In this case, valid values for the Congestion Level field range from 3950 0 to 7, where 0 indicates the least congested and 7 indicates the 3951 most congested subsystem. 3953 4. Procedures 3955 The SUA layer needs to respond to various local primitives it 3956 receives from other layers as well as the messages that it receives 3957 from the peer SUA layer. This section describes the SUA procedures 3958 in response to these events. 3960 4.1 Procedures to Support the SUA-User Layer 3962 4.1.1 Receipt of Primitives from SCCP 3964 When an SCCP Subsystem Management (SCMG) message is received from the 3965 SS7 network, the SGP needs to determine whether there are concerned 3966 Application Servers interested in subsystem status changes. The SUA 3967 management function is informed with the N-State or N-Coord primitive 3968 upon which it formats and transfers the applicable SNMM message to 3969 the list of concerned ASPs using stream ID "0". 3971 When MTP-3 Management indications are received (MTP-PAUSE, MTP- 3972 RESUME, MTP-STATUS), SCCP Subsystem Management determines whether 3973 there are concerned local SCCP-users. When these local SCCP-users are 3974 in fact Application Servers, serviced by ASPs, SUA management is 3975 informed with the N-PCSTATE indication primitive upon which it 3976 formats and transfers the applicable SNM message (DUNA, DAVA, DRST or 3977 SCON) to the list of concerned ASPs using stream ID "0". 3979 The SUA message distribution function determines the Application 3980 Server (AS) based on comparing the information in the N-UNITDATA 3981 request primitive with a provisioned Routing Key. 3983 From the list of ASPs within the AS table, an ASP in the ASP-ACTIVE 3984 state is selected and a DATA message is constructed and issued on the 3985 corresponding SCTP association. If more than one ASP is in the ASP- 3986 ACTIVE state (i.e., traffic is to be load-shared across more than one 3987 ASP), one of the ASPs in the ASP_ACTIVE state is selected from the 3988 list. If the ASPs are in Broadcast Mode, all active ASPs will be 3989 selected and the message sent to each of the active ASPs. The 3990 selection algorithm is implementation dependent but could, for 3991 example, be round robin or based on the SLS. The appropriate 3992 selection algorithm must be chosen carefully as it is dependent on 3993 application assumptions and understanding of the degree of state 3994 coordination between the ASP_ACTIVE ASPs in the AS. 3996 In addition, the message needs to be sent on the appropriate SCTP 3997 stream, again taking care to meet the message sequencing needs of the 3998 signalling application. DATA messages MUST be sent on an SCTP stream 3999 other than stream '0' when there is more than one stream. 4001 When there is no Routing Key match, or only a partial match, for an 4002 incoming SS7 message, a default treatment MAY be specified. Possible 4003 solutions are to provide a default Application Server at the SGP that 4004 directs all unallocated traffic to a (set of) default ASP(s), or to 4005 drop the message and provide a notification to Layer Management in an 4006 M-ERROR indication primitive. The treatment of unallocated traffic 4007 is implementation dependent. 4009 4.2 Receipt of Primitives from the Layer Management 4011 On receiving primitives from the local Layer Management, the SUA 4012 layer will take the requested action and provide an appropriate 4013 response primitive to Layer Management. 4015 An M-SCTP_ESTABLISH request primitive from Layer Management at an ASP 4016 or IPSP will initiate the establishment of an SCTP association. The 4017 SUA layer will attempt to establish an SCTP association with the 4018 remote SUA peer by sending an SCTP-ASSOCIATE primitive to the local 4019 SCTP layer. 4021 When an SCTP association has been successfully established, the SCTP 4022 will send an SCTP-COMMUNICATION_UP notification primitive to the 4023 local SUA layer. At the ASP or IPSP that initiated the request, the 4024 SUA layer will send an M-SCTP_ESTABLISH confirm primitive to Layer 4025 Management when the association setup is complete. At the peer SUA 4026 layer, an M-SCTP_ESTABLISH indication primitive is sent to Layer 4027 Management upon successful completion of an incoming SCTP association 4028 setup. 4030 An M-SCTP_RELEASE request primitive from Layer Management initates 4031 the shutdown of an SCTP association. The SUA layer accomplishes a 4032 graceful shutdown of the SCTP association by sending an SCTP-SHUTDOWN 4033 primitive to the SCTP layer. 4035 When the graceful shutdown of the SCTP association has been 4036 accomplished, the SCTP layer returns an SCTP-SHUTDOWN_COMPLETE 4037 notification primitive to the local SUA layer. At the SUA Layer that 4038 initiated the request, the SUA layer will send an M-SCTP_RELEASE 4039 confirm primitive to Layer Management when the association shutdown 4040 is complete. At the peer SUA Layer, an M-SCTP_RELEASE indication 4041 primitive is sent to Layer Management upon abort or successful 4042 shutdown of an SCTP association. 4044 An M-SCTP_STATUS request primitive supports a Layer Management query 4045 of the local status of a particular SCTP association. The SUA layer 4046 simply maps the M-SCTP_STATUS request primitive to an SCTP-STATUS 4047 primitive to the SCTP layer. When the SCTP responds, the SUA layer 4048 maps the association status information to an M-SCTP_STATUS confirm 4049 primitive. No peer protocol is invoked. 4051 Similar LM-to-SUA-to-SCTP and/or SCTP-to-SUA-to-LM primitive mappings 4052 can be described for the various other SCTP Upper Layer primitives in 4053 RFC 2960 [2960] such as INITIALIZE, SET PRIMARY, CHANGE HEARTBEAT, 4054 REQUEST HEARTBEAT, GET SRTT REPORT, SET FAILURE THRESHOLD, SET 4055 PROTOCOL PARAMETERS, DESTROY SCTP INSTANCE, SEND FAILURE, AND NETWORK 4056 STATUS CHANGE. Alternatively, these SCTP Upper Layer primitives (and 4057 Status as well) can be considered for modeling purposes as a Layer 4058 Management interaction directly with the SCTP Layer. 4060 M-NOTIFY indication and M-ERROR indication primitives indicate to 4061 Layer Management the notification or error information contained in a 4062 received SUA Notify or Error message respectively. These indications 4063 can also be generated based on local SUA events. 4065 An M-ASP_STATUS request primitive supports a Layer Management query 4066 of the status of a particular local or remote ASP. The SUA layer 4067 responds with the status in an M-ASP_STATUS confirm primitive. No 4068 SUA peer protocol is invoked. An M-AS_STATUS request supports a Layer 4069 Management query of the status of a particular AS. The SUA responds 4070 with an M-AS_STATUS confirm primitive. No SUA peer protocol is 4071 invoked. 4073 M-ASP_UP request, M-ASP_DOWN request, M-ASP_ACTIVE request and M- 4074 ASP_INACTIVE request primitives allow Layer Management at an ASP to 4075 initiate state changes. Upon successful completion, a corresponding 4076 confirm primitive is provided by the SUA layer to Layer Management. 4077 If an invocation is unsuccessful, an Error indication primitive is 4078 provided in the primitive. These requests result in outgoing ASP Up, 4079 ASP Down, ASP Active and ASP Inactive messages to the remote SUA peer 4080 at an SGP or IPSP. 4082 4.2.1 Receipt of SUA Peer Management Messages 4084 Upon successful state changes resulting from reception of ASP Up, ASP 4085 Down, ASP Active and ASP Inactive messages from a peer SUA, the SUA 4086 layer MAY invoke corresponding M-ASP_UP, M-ASP_DOWN, M-ASP_ACTIVE and 4087 M-ASP_INACTIVE, M-AS_ACTIVE, M-AS_INACTIVE, and M-AS_DOWN indication 4088 primitives to the local Layer Management. 4090 M-NOTIFY indication and M-ERROR indication primitives indicate to 4091 Layer Management the notification or error information contained in a 4092 received SUA Notify or Error message. These indications can also be 4093 generated based on local SUA events. 4095 All non-Transfer messages, except BEAT and BEAT Ack, SHOULD be sent 4096 with sequenced delivery to ensure ordering. All non-Transfer 4097 messages, with the exception of ASPTM, BEAT and BEAT Ack messages 4098 SHOULD be sent on SCTP stream '0'. ASPTM messages MAY be sent on one 4099 of the streams used to carry data traffic related to the Routing 4100 Context(s), to minimize possible message loss. BEAT and BEAT Ack 4101 messages MAY be sent using out-of-order delivery, and MAY be sent on 4102 any stream. 4104 4.3 AS and ASP State Maintenance 4106 The SUA layer on the SGP maintains the state of each remote ASP, in 4107 each Application Server that the ASP is configured to receive 4108 traffic, as input to the SUA message distribution function. 4109 Similarly, where IPSPs use SUA in a point-to-point fashion, the SUA 4110 layer in an IPSP maintains the state of remote IPSPs. 4112 Two IPSP models are defined with regards to the number of messages 4113 that are needed to a IPSP state change. They are defined as follows: 4115 1 IPSP Single Exchange (SE) model. Only a single exchange of 4116 ASPTM or ASPSM messages is needed to change the IPSP state. 4117 This means that a set of request from one end and acknowledge 4118 from the other will be enough. 4120 2 IPSP Double Exchange (DE) model. Both IPSPs have to send 4121 request messages and both IPSPs have to acknowledge the request 4122 messages from the other end. This results in a double exchange 4123 of ASPTM and ASPSM message, one from each end. This 4124 configuration supports dynamic routing key configuration by 4125 using RKM messages in the same way as ASP-SGP scenario. 4127 In order to ensure interoperability, an SUA implementation supporting 4128 IPSP communication MUST support IPSP SE model and MAY implement IPSP 4129 DE model. 4131 In section 4.3.1: ASP/IPSP States, only the SGP-ASP and the IPSP SE 4132 scenarios are described. For the IPSP DE model, both IPSPs MUST 4133 follow the SGP side of the SGP-ASP procedures. 4135 In section 4.3.2, only the SGP-ASP scenario is described. All of the 4136 procedures referring to an AS served by ASPs are also applicable to 4137 ASes served by IPSPs. 4139 In section 4.3.3, only the Management procedures for the SGP-ASP 4140 scenario are described. The corresponding Management procedures for 4141 IPSPs are directly inferred. 4143 The remaining sections contain specific IPSP Considerations sub- 4144 sections. 4146 4.3.1 ASP States 4148 The state of each remote ASP/IPSP, in each AS that it is configured 4149 to operate, is maintained in the peer SUA layer (i.e. in the SGP or 4150 peer IPSP, respectively). The state of a particular ASP/IPSP in a 4151 particular AS changes due to events. The events include: 4153 * Reception of messages from the peer SUA layer at the ASP/IPSP; 4154 * Reception of some messages from the peer SUA layer at other 4155 ASPs/IPSPs in the AS (e.g., ASP Active message indicating 4156 "Override"); 4157 * Reception of indications from the SCTP layer; or 4158 * Local Management intervention. 4160 The ASP/IPSP state transition diagram is shown in Figure 3. The 4161 possible states of an ASP/IPSP are: 4163 ASP-DOWN: The remote SUA peer at the ASP/IPSP is unavailable and/or 4164 the related SCTP association is down. Initially all ASPs/IPSPs will 4165 be in this state. An ASP/IPSP in this state SHOULD NOT be sent any 4166 SUA messages, with the exception of Heartbeat, ASP Down Ack and Error 4167 messages. 4169 ASP-INACTIVE: The remote SUA peer at the ASP/IPSP is available (and 4170 the related SCTP association is up) but application traffic is 4171 stopped. In this state the ASP/IPSP SHOULD NOT be sent any DATA or 4172 SSNM messages for the AS for which the ASP/IPSP is inactive. 4174 ASP-ACTIVE: The remote SUA peer at the ASP/IPSP is available and 4175 application traffic is active (for a particular Routing Context or 4176 set of Routing Contexts). 4178 Figure 4: ASP/IPSP State Transition Diagram, per AS 4180 +--------------+ 4181 | | 4182 +----------------------| ASP-ACTIVE | 4183 | Other ASP/ +-------| | 4184 | IPSP in AS | +--------------+ 4185 | Overrides | ^ | 4186 | | ASPAC/ | | ASPIA/ 4187 | |[ASPAC-Ack]| | [ASPIA-Ack] 4188 | | | v 4189 | | +--------------+ 4190 | | | | 4191 | +------>| ASP-INACTIVE | 4192 | | | 4193 | +--------------+ 4194 | ^ | 4195 ASPDN/ | | | ASPDN / 4196 [ASPDN-Ack/]| ASPUP/ | | [ASPDN-Ack /] 4197 SCTP CDI/ | [ASPUP-Ack] | | SCTP CDI/ 4198 SCTP RI | | | SCTP RI 4199 | | v 4200 | +--------------+ 4201 | | | 4202 +--------------------->| ASP-DOWN | 4203 | | 4204 +--------------+ 4206 The transitions in brackets are just valid for the IPSP SE model 4207 communication while the rest are valid for both ASPs and IPSPs. 4209 SCTP CDI: The SCTP CDI denotes the local SCTP layer's Communication 4210 Down Indication to the Upper Layer Protocol (SUA) on an SGP. The 4211 local SCTP layer will send this indication when it detects the loss 4212 of connectivity to the ASP's peer SCTP layer. SCTP CDI is understood 4213 as either a SHUTDOWN_COMPLETE notification or COMMUNICATION_LOST 4214 notification from the SCTP layer. 4216 SCTP RI: The local SCTP layer's Restart indication to the upper layer 4217 protocol (SUA) on an SG. The local SCTP will send this indication 4218 when it detects a restart from the ASP's peer SCTP layer. 4220 4.3.2 AS States 4222 The state of the AS is maintained in the SUA layer on the SGP. The 4223 state of an AS changes due to events. These events include: 4225 * ASP state transitions 4226 * Recovery timer triggers 4228 The possible states of an AS are: 4230 AS-DOWN: The Application Server is unavailable. This state 4231 implies that all related ASPs are in the ASP-DOWN state 4232 for this AS. Initially the AS will be in this state. An 4233 Application Server is in the AS-DOWN state before it can 4234 be removed from a configuration. 4236 AS-INACTIVE: The Application Server is available but no application 4237 traffic is active (i.e., one or more related ASPs are in 4238 the ASP-INACTIVE state, but none in the ASP-ACTIVE 4239 state). The recovery timer T(r) is not running or has 4240 expired. 4242 AS-ACTIVE: The Application Server is available and application 4243 traffic is active. This state implies that at least one 4244 ASP is in the ASP-ACTIVE state. 4246 AS-PENDING: An active ASP has transitioned to ASP-INACTIVE or ASP- 4247 DOWN and it was the last remaining active ASP in the AS. 4248 A recovery timer T(r) SHOULD be started and all incoming 4249 signalling messages SHOULD be queued by the SGP. If an 4250 ASP becomes ASP-ACTIVE before T(r) expires, the AS is 4251 moved to the AS-ACTIVE state and all the queued messages 4252 will be sent to the ASP. 4254 If T(r) expires before an ASP becomes ASP-ACTIVE, and the SGP has no 4255 other alternative, the SGP may stop queueing messages and discard all 4256 previously queued messages. The AS will move to the AS-INACTIVE state 4257 if at least one ASP is in ASP-INACTIVE state, otherwise it will move 4258 to AS-DOWN state. 4260 Figure 5 shows an example AS state machine for the case where the 4261 AS/ASP data is pre-configured. For other cases where the AS/ASP 4262 configuration data is created dynamically, there would be differences 4263 in the state machine, especially at creation of the AS. 4265 For example, where the AS/ASP configuration data is not created until 4266 Registration of the first ASP, the AS-INACTIVE state is entered 4267 directly upon the first successful REG REQ from an ASP. Another 4268 example is where the AS/ASP configuration data is not created until 4269 the first ASP successfully enters the ASP-ACTIVE state. In this case 4270 the AS-ACTIVE state is entered directly. 4272 Figure 5: AS State Transition Diagram 4274 +----------+ one ASP trans to ACTIVE +-------------+ 4275 | AS- |---------------------------->| AS- | 4276 | INACTIVE | | ACTIVE | 4277 | |<--- | | 4278 +----------+ \ +-------------+ 4279 ^ | \ Tr Expiry, ^ | 4280 | | \ at least one | | 4281 | | \ ASP in ASP-INACTIVE | | 4282 | | \ | | 4283 | | \ | | 4284 | | \ | | 4285 one ASP | | all ASP \ one ASP | | Last ACTIVE 4286 trans | | trans to \ trans to | | ASP trans to 4287 to | | ASP-DOWN -------\ ASP- | | ASP-INACTIVE 4288 ASP- | | \ ACTIVE | | or ASP-DOWN 4289 INACTIVE| | \ | | (start Tr) 4290 | | \ | | 4291 | | \ | | 4292 | v \ | v 4293 +----------+ \ +-------------+ 4294 | | --| | 4295 | AS-DOWN | | AS-PENDING | 4296 | | | (queueing) | 4297 | |<----------------------------| | 4298 +----------+ Tr Expiry and no ASP +-------------+ 4299 in ASP-INACTIVE state 4301 Tr = Recovery Timer 4303 4.3.2.1 IPSP Considerations 4305 The AS state diagram for the AS-SG case is applicable for IPSP 4306 communication. 4308 4.3.3 SUA Management Procedures for Primitives 4310 Before the establishment of an SCTP association the ASP state at both 4311 the SGP and ASP is assumed to be in the state ASP-DOWN. 4313 Once the SCTP association is established (see Section 4.2.1) and 4314 assuming that the local SUA-User is ready, the local SUA ASP 4315 Maintenance (ASPM) function will initiate the relevant procedures, 4316 using the ASP Up/ASP Down/ASP Active/ASP Inactive messages to convey 4317 the ASP state to the SGP (see Section 4.3.4). 4319 If the SUA layer subsequently receives an SCTP-COMMUNICATION_DOWN or 4320 SCTP-RESTART indication primitive from the underlying SCTP layer, it 4321 will inform the Layer Management by invoking the M-SCTP_STATUS 4322 indication primitive. The state of the ASP will be moved to ASP- 4323 DOWN. 4325 In the case of SCTP-COMMUNICATION_DOWN, the SCTP client MAY try to 4326 re-establish the SCTP association. This MAY be done by the SUA layer 4327 automatically, or Layer Management MAY re-establish using the M- 4328 SCTP_ESTABLISH request primitive. 4330 In the case of an SCTP-RESTART indication at an ASP, the ASP is now 4331 considered by its SUA peer to be in the ASP-DOWN state. The ASP, if 4332 it is to recover, must begin any recovery with the ASP-Up procedure. 4334 4.3.4 ASPM Procedures for Peer-to-Peer Messages 4336 4.3.4.1 ASP Up Procedures 4338 After an ASP has successfully established an SCTP association to an 4339 SGP, the SGP waits for the ASP to send an ASP Up message, indicating 4340 that the ASP SUA peer is available. The ASP is always the initiator 4341 of the ASP Up message. This action MAY be initiated at the ASP by an 4342 M-ASP_UP request primitive from Layer Management or MAY be initiated 4343 automatically by an SUA management function. 4345 When an ASP Up message is received at an SGP and internally the 4346 remote ASP is in the ASP-DOWN state and not considered locked-out for 4347 local management reasons, the SGP marks the remote ASP in the state 4348 ASP-INACTIVE and informs Layer Management with an M-ASP_Up indication 4349 primitive. If the SGP is aware, via current configuration data, 4350 which Application Servers the ASP is configured to operate in, the 4351 SGP updates the ASP state to ASP-INACTIVE in each AS that it is a 4352 member. 4354 Alternatively, the SGP may move the ASP into a pool of Inactive ASPs 4355 available for future configuration within Application Server(s), 4356 determined in a subsequent Registration Request or ASP Active 4357 procedure. If the ASP Up message contains an ASP Identifier, the SGP 4358 should save the ASP Identifier for that ASP. The SGP MUST send an 4359 ASP Up Ack message in response to a received ASP Up message even if 4360 the ASP is already marked as ASP-INACTIVE at the SGP. 4362 If for any local reason (e.g., management lock-out) the SGP cannot 4363 respond with an ASP Up Ack message, the SGP responds to an ASP Up 4364 message with an Error message with Reason "Refused - Management 4365 Blocking". 4367 At the ASP, the ASP Up Ack message received is not acknowledged. 4368 Layer Management is informed with an M-ASP_UP confirm primitive. 4370 When the ASP sends an ASP Up message it starts timer T(ack). If the 4371 ASP does not receive a response to an ASP Up message within T(ack), 4372 the ASP MAY restart T(ack) and resend ASP Up messages until it 4373 receives an ASP Up Ack message. T(ack) is provisionable, with a 4374 default of 2 seconds. Alternatively, retransmission of ASP Up 4375 messages MAY be put under control of Layer Management. In this 4376 method, expiry of T(ack) results in an M-ASP_UP confirm primitive 4377 carrying a negative indication. 4379 The ASP must wait for the ASP Up Ack message before sending any other 4380 SUA messages (e.g., ASP Active or REG REQ). If the SGP receives any 4381 other SUA messages before ASPUP message is received (other than ASPDN 4382 - see section 4.3.4.2), the SGP SHOULD discard them. 4384 If an ASP Up message is received and internally the remote ASP is in 4385 the ASP-ACTIVE state, an ASP Up Ack message is returned, as well as 4386 an Error message ("Unexpected Message), and the remote ASP state is 4387 changed to ASP-INACTIVE in all relevant Application Servers. 4389 If an ASP Up message is received and internally the remote ASP is 4390 already in the ASP-INACTIVE state, an ASP Up Ack message is returned 4391 and no further action is taken. 4393 4.3.4.1.1 SUA Version Control 4395 If an ASP Up message with an unsupported version is received, the 4396 receiving end responds with an Error message, indicating the version 4397 the receiving node supports and notifies Layer Management. 4399 This is useful when protocol version upgrades are being performed in 4400 a network. A node upgraded to a newer version should support the 4401 older versions used on other nodes it is communicating with. Because 4402 ASPs initiate the ASP Up procedure it is assumed that the Error 4403 message would normally come from the SGP. 4405 4.3.4.1.2 IPSP Considerations 4407 An IPSP may be considered in the ASP-INACTIVE state after and ASPUP 4408 or ASPUP Ack has been received from it. An IPSP can be considered 4409 in the ASP-DOWN state after an ASPDN or ASPDN Ack has been received 4410 from it. The IPSP may inform Layer Management of the change in state 4411 of the remote IPSP using M-ASP_UP or M-ASP_DN indication or 4412 confirmation primitives. 4414 Alternatively, when using IPSP DE model, an interchange of ASP Up 4415 messages from each end MUST be performed. Four messages are needed 4416 for completion. 4418 If for any local reason (e.g., management lock-out) and IPSP cannot 4419 respond to an ASP Up message with an ASP Up Ack message, it responds 4420 to an ASP Up message with an Error message with Reason "Refused - 4421 Management Blocking" and leaves the remote IPSP in the ASP-DOWN 4422 state. 4424 4.3.4.2 ASP Down Procedures 4426 The ASP will send an ASP Down message to an SGP when the ASP wishes 4427 to be removed from service in all Application Servers that it is a 4428 member and no longer receive any Connectionless or Connection - 4429 Oriented, SSNM or ASPTM messages. This action MAY be initiated at 4430 the ASP by an M-ASP_DOWN request primitive from Layer Management or 4431 MAY be initiated automatically by an SUA management function. 4433 Whether the ASP is permanently removed from any AS is a function of 4434 configuration management. In the case where the ASP previously used 4435 the Registration procedures (see Section 4.4.1) to register within 4436 Application Servers but has not deregistered from all of them prior 4437 to sending the ASP Down message, the SGP MUST consider the ASP as 4438 Deregistered in all Application Servers that it is still a member. 4440 The SGP marks the ASP as ASP-DOWN, informs Layer Management with an 4441 M-ASP_Down indication primitive, and returns an ASP Down Ack message 4442 to the ASP. 4444 The SGP MUST send an ASP Down Ack message in response to a received 4445 ASP Down message from the ASP even if the ASP is already marked as 4446 ASP-DOWN at the SGP. 4448 At the ASP, the ASP Down Ack message received is not acknowledged. 4449 Layer Management is informed with an M-ASP_DOWN confirm primitive. 4450 If the ASP receives an ASP Down Ack without having sent an ASP Down 4451 message, the ASP should now consider itself as in the ASP-DOWN state. 4452 If the ASP was previously in the ASP-ACTIVE or ASP_INACTIVE state, 4453 the ASP should then initiate procedures to return itself to its 4454 previous state. 4456 When the ASP sends an ASP Down message it starts timer T(ack). If 4457 the ASP does not receive a response to an ASP Down message within 4458 T(ack), the ASP MAY restart T(ack) and resend ASP Down messages until 4459 it receives an ASP Down Ack message. T(ack) is provisionable, with a 4460 default of 2 seconds. Alternatively, retransmission of ASP Down 4461 messages MAY be put under control of Layer Management. In this 4462 method, expiry of T(ack) results in an M-ASP_DOWN confirm primitive 4463 carrying a negative indication. 4465 4.3.4.3 ASP Active Procedures 4467 Anytime after the ASP has received an ASP Up Ack message from the SGP 4468 or IPSP, the ASP MAY send an ASP Active message to the SGP indicating 4469 that the ASP is ready to start processing traffic. This action MAY 4470 be initiated at the ASP by an M-ASP_ACTIVE request primitive from 4471 Layer Management or MAY be initiated automatically by an SUA 4472 management function. In the case where an ASP wishes to process the 4473 traffic for more than one Application Server across a common SCTP 4474 association, the ASP Active message(s) SHOULD contain a list of one 4475 or more Routing Contexts to indicate for which Application Servers 4476 the ASP Active message applies. It is not necessary for the ASP to 4477 include all Routing Contexts of interest in a single ASP Active 4478 message, thus requesting to become active in all Routing Contexts at 4479 the same time. Multiple ASP Active messages MAY be used to activate 4480 within the Application Servers independently, or in sets. In the 4481 case where an ASP Active message does not contain a Routing Context 4482 parameter, the receiver must know, via configuration data, which 4483 Application Server(s) the ASP is a member. 4485 For the Application Servers that the ASP can successfully activate, 4486 the SGP or IPSP responds with one or more ASP Active Ack messages, 4487 including the associated Routing Context(s) and reflecting any 4488 Traffic Mode Type values present in the related ASP Active message. 4489 The Routing Context parameter MUST be included in the ASP Active Ack 4490 message(s) if the received ASP Active message contained any Routing 4491 Contexts. Depending on any Traffic Mode Type request in the ASP 4492 Active message or local configuration data if there is no request, 4493 the SGP moves the ASP to the correct ASP traffic state within the 4494 associated Application Server(s). Layer Management is informed with 4495 an M-ASP_Active indication. If the SGP or IPSP receives any Data 4496 messages before an ASP Active message is received, the SGP or IPSP 4497 MAY discard them. By sending an ASP Active Ack message, the SGP or 4498 IPSP is now ready to receive and send traffic for the related Routing 4499 Context(s). The ASP SHOULD NOT send Data messages for the related 4500 Routing Context(s) before receiving an ASP Active Ack message, or it 4501 will risk message loss. 4503 Multiple ASP Active Ack messages MAY be used in response to an ASP 4504 Active message containing multiple Routing Contexts, allowing the SGP 4505 or IPSP to independently acknowledge the ASP Active message for 4506 different (sets of) Routing Contexts. The SGP or IPSP MUST send an 4507 Error message ("Invalid Routing Context") for each Routing Context 4508 value that cannot be successfully activated. 4510 In the case where an "out-of-the-blue" ASP Active message is received 4511 (i.e., the ASP has not registered with the SG or the SG has no static 4512 configuration data for the ASP), the message MAY be silently 4513 discarded. 4515 The SGP MUST send an ASP Active Ack message in response to a received 4516 ASP Active message from the ASP, if the ASP is already marked in the 4517 ASP-ACTIVE state at the SGP. 4519 At the ASP, the ASP Active Ack message received is not acknowledged. 4520 Layer Management is informed with an M-ASP_ACTIVE confirm primitive. 4521 It is possible for the ASP to receive Data message(s) before the ASP 4522 Active Ack message as the ASP Active Ack and Data messages from an SG 4523 or IPSP may be sent on different SCTP streams. Message loss is 4524 possible, as the ASP does not consider itself in the ASP-ACTIVE state 4525 until reception of the ASP Active Ack message. 4527 When the ASP sends an ASP Active message it starts timer T(ack). If 4528 the ASP does not receive a response to an ASP Active message within 4529 T(ack), the ASP MAY restart T(ack) and resend ASP Active messages 4530 until it receives an ASP Active Ack message. T(ack) is 4531 provisionable, with a default of 2 seconds. Alternatively, 4532 retransmission of ASP Active messages MAY be put under control of 4533 Layer Management. In this method, expiry of T(ack) results in an M- 4534 ASP_ACTIVE confirm primitive carrying a negative indication. 4536 There are three modes of Application Server traffic handling in the 4537 SGP SUA layer: Override, Load-share and Broadcast. When included, 4538 the Traffic Mode Type parameter in the ASP Active message indicates 4539 the traffic-handling mode to be used in a particular Application 4540 Server. If the SGP determines that the mode indicated in an ASP 4541 Active message is unsupported or incompatible with the mode currently 4542 configured for the AS, the SGP responds with an Error message 4543 ("Unsupported / Invalid Traffic Handling Mode"). If the traffic- 4544 handling mode of the Application Server is not already known via 4545 configuration data, then the traffic-handling mode indicated in the 4546 first ASP Active message causing the transition of the Application 4547 Server state to AS-ACTIVE MAY be used to set the mode. 4549 In the case of an Override mode AS, reception of an ASP Active 4550 message at an SGP causes the (re)direction of all traffic for the AS 4551 to the ASP that sent the ASP Active message. Any previously active 4552 ASP in the AS is now considered to be in state ASP-INACTIVE and 4553 SHOULD no longer receive traffic from the SGP within the AS. The SGP 4554 or IPSP then MUST send a Notify message ("Alternate ASP Active") to 4555 the previously active ASP in the AS, and SHOULD stop traffic to/from 4556 that ASP. The ASP receiving this Notify MUST consider itself now in 4557 the ASP-INACTIVE state, if it is not already aware of this via inter- 4558 ASP communication with the Overriding ASP. 4560 In the case of a Loadshare mode AS, reception of an ASP Active 4561 message at an SGP or IPSP causes the direction of traffic to the ASP 4562 sending the ASP Active message, in addition to all the other ASPs 4563 that are currently active in the AS. The algorithm at the SGP for 4564 load-sharing traffic within an AS to all the active ASPs is 4565 implementation dependent. The algorithm could, for example, be round 4566 robin or based on information in the Data message (e.g., the SLS or 4567 SSN). 4569 An SGP or IPSP, upon reception of an ASP Active message for the first 4570 ASP in a Loadshare AS, MAY choose not to direct traffic to a newly 4571 active ASP until it determines that there are sufficient resources to 4572 handle the expected load (e.g., until there are "n" ASPs in state 4573 ASP-ACTIVE in the AS). 4575 All ASPs within a load-sharing mode AS must be able to process any 4576 Data message received for the AS, to accommodate any potential fail- 4577 over or rebalancing of the offered load. 4579 In the case of a Broadcast mode AS, reception of an ASP Active 4580 message at an SGP or IPSP causes the direction of traffic to the ASP 4581 sending the ASP Active message, in addition to all the other ASPs 4582 that are currently active in the AS. The algorithm at the SGP for 4583 broadcasting traffic within an AS to all the active ASPs is a simple 4584 broadcast algorithm, where every message is sent to each of the 4585 active ASPs. An SGP or IPSP, upon reception of an ASP Active message 4586 for the first ASP in a Broadcast AS, MAY choose not to direct traffic 4587 to a newly active ASP until it determines that there are sufficient 4588 resources to handle the expected load (e.g., until there are "n" ASPs 4589 in state ASP-ACTIVE in the AS). 4591 Whenever an ASP in a Broadcast mode AS becomes ASP-ACTIVE, the SGP 4592 MUST tag the first DATA message broadcast in each SCTP stream with a 4593 unique Correlation Id parameter. The purpose of this Correlation Id 4594 is to permit the newly active ASP to synchronize it's processing of 4595 traffic in each ordered stream with the other ASPs in the broadcast 4596 group. 4598 4.3.4.3.1 IPSP Consideratoins 4600 Either of the IPSPs can initiate communication. When an IPSP receives 4601 an ASP Active, it should mark the peer as ASP-ACTIVE and return an 4602 ASP Active Ack message. An ASP receiving an ASP Active Ack message 4603 may mark the peer as ASP-Active, if it is not already in the ASP- 4604 ACTIVE state. 4606 Alternatively, when using IPSP DE model, an interchange of ASP Active 4607 messages from each end MUST be performed. Four messages are needed 4608 for completion. 4610 4.3.4.4 ASP Inactive Procedures 4612 When an ASP wishes to withdraw from receiving traffic within an AS, 4613 or the ASP wants to initiate the process of deactivation, the ASP 4614 sends an ASP Inactive message to the SGP or IPSP. 4616 An ASP Inactive message MUST be always responded by the peer 4617 (although other messages may be sent in the middle): 4619 - If the corresponding RK is registered (statically or 4620 dynamically), the peer should respond with an ASP Inactive Ack 4621 message. 4622 - If the RK is not registered, or the RC information is not 4623 valid, the peer must respond with an ERROR message with Error 4624 Code = "Invalid Routing Context". 4625 - If the RC is missing and its specification is needed according 4626 to the used configuration, the peer must respond with an ERROR 4627 message with Error Code = "No Configured AS for ASP". 4629 The action of sending the ASP Inactive message MAY be initiated at 4630 the ASP by an M-ASP_INACTIVE request primitive from Layer Management 4631 or MAY be initiated automatically by an SUA management function. In 4632 the case where an ASP is processing the traffic for more than one 4633 Application Server across a common SCTP association, the ASP Inactive 4634 message contains one or more Routing Contexts to indicate for which 4635 Application Servers the ASP Inactive message applies. 4637 In the case where an ASP Inactive message does not contain a Routing 4638 Context parameter, the receiver must know, via configuration data, 4639 which Application Servers the ASP is a member and move the ASP to the 4640 ASP-INACTIVE state in each all Application Servers. 4642 In the case of an Override mode AS, where another ASP has already 4643 taken over the traffic within the AS with an ASP Active ("Override") 4644 message, the ASP that sends the ASP Inactive message is already 4645 considered by the SGP to be in state ASP-INACTIVE. An ASP Inactive 4646 Ack message is sent to the ASP, after ensuring that all traffic is 4647 stopped to the ASP. 4649 In the case of a Load-share mode AS, the SGP moves the ASP to the 4650 ASP-INACTIVE state and the AS traffic is re-allocated across the 4651 remaining ASPs in the state ASP-ACTIVE, as per the load-sharing 4652 algorithm currently used within the AS. A Notify message 4653 ("Insufficient ASP resources active in AS") MAY be sent to all 4654 inactive ASPs, if required. An ASP Inactive Ack message is sent to 4655 the ASP after all traffic is halted and Layer Management is informed 4656 with an M-ASP_INACTIVE indication primitive. 4658 In the case of a Broadcast mode AS, the SGP moves the ASP to the ASP- 4659 INACTIVE state and the AS traffic is broadcast only to the remaining 4660 ASPs in the state ASP-ACTIVE. A Notify message ("Insufficient ASP 4661 resources active in AS") MAY be sent to all inactive ASPs, if 4662 required. An ASP Inactive Ack message is sent to the ASP after all 4663 traffic is halted and Layer Management is informed with an M- 4664 ASP_INACTIVE indication primitive. 4666 Multiple ASP Inactive Ack messages MAY be used in response to an ASP 4667 Inactive message containing multiple Routing Contexts, allowing the 4668 SGP or IPSP to independently acknowledge for different (sets of) 4669 Routing Contexts. The SGP or IPSP sends an Error message ("Invalid 4670 Routing Context") message for each invalid or unconfigured Routing 4671 Context value in a received ASP Inactive message. 4673 The SGP MUST send an ASP Inactive Ack message in response to a 4674 received ASP Inactive message from the ASP and the ASP is already 4675 marked as ASP-INACTIVE at the SGP. 4677 At the ASP, the ASP Inactive Ack message received is not 4678 acknowledged. Layer Management is informed with an M-ASP_INACTIVE 4679 confirm primitive. If the ASP receives an ASP Inactive Ack without 4680 having sent an ASP Inactive message, the ASP should now consider 4681 itself as in the ASP-INACTIVE state. If the ASP was previously in 4682 the ASP-ACTIVE state, the ASP should then initiate procedures to 4683 return itself to its previous state. When the ASP sends an ASP 4684 Inactive message it starts timer T(ack). If the ASP does not receive 4685 a response to an ASP Inactive message within T(ack), the ASP MAY 4686 restart T(ack) and resend ASP Inactive messages until it receives an 4687 ASP Inactive Ack message. T(ack) is provisionable, with a default of 4688 2 seconds. Alternatively, retransmission of ASP Inactive messages 4689 MAY be put under control of Layer Management. In this method, expiry 4690 of T(ack) results in a M-ASP_Inactive confirm primitive carrying a 4691 negative indication. 4693 If no other ASPs in the Application Server are in the state ASP- 4694 ACTIVE, the SGP MUST send a Notify message ("AS-Pending") to all of 4695 the ASPs in the AS which are in the state ASP-INACTIVE. The SGP 4696 SHOULD start buffering the incoming messages for T(r) seconds, after 4697 which messages MAY be discarded. T(r) is configurable by the network 4698 operator. If the SGP receives an ASP Active message from an ASP in 4699 the AS before expiry of T(r), the buffered traffic is directed to 4700 that ASP and the timer is cancelled. If T(r) expires, the AS is 4701 moved to the AS-INACTIVE state. 4703 4.3.4.4.1 IPSP Considerations 4705 An IPSP may be considered in the ASP-INACTIVE state by a remote IPSP 4706 after an ASP Inactive or ASP Inactive Ack message has been received 4707 from it. 4709 Alternatively, when using IPSP DE model, an interchange of ASP 4710 Inactive messages from each end MUST be performed. Four messages are 4711 needed for completion. 4713 4.3.4.5 Notify Procedures 4715 A Notify message reflecting a change in the AS state MUST be sent to 4716 all ASPs in the AS, except those in the ASP-DOWN state, 4717 withappropriate Status Information and any ASP Identifier of the 4718 failed ASP. At the ASP, Layer Management is informed with an M- 4719 NOTIFY indication primitive. The Notify message must be sent whether 4720 the AS state change was a result of an ASP failure or reception of an 4721 ASP State management (ASPSM) / ASP Traffic Management (ASPTM) 4722 message. In the second case, the Notify message MUST be sent after 4723 any ASP State or Traffic Management related acknowledgement messages 4724 (e.g., ASP Up Ack, ASP Down Ack, ASP Active Ack, or ASP Inactive 4725 Ack). 4727 In the case where a Notify ("AS-PENDING") message is sent by an SGP 4728 that now has no ASPs active to service the traffic, or where a Notify 4729 ("Insufficient ASP resources active in AS") message MUST be sent in 4730 the Loadshare or Broadcast mode, the Notify message does not 4731 explicitly compel the ASP(s) receiving the message to become active. 4733 The ASPs remain in control of what (and when) traffic action is 4734 taken. 4736 In the case where a Notify message does not contain a Routing Context 4737 parameter, the receiver must know, via configuration data, of which 4738 Application Servers the ASP is a member and take the appropriate 4739 action in each AS. 4741 4.3.4.5.1 IPSP Considerations (NTFY) 4743 Notify works in the same manner as in the SG-AS case. One of the 4744 IPSPs can send this message to any remote IPSP that is not in the 4745 ASP-DOWN state. 4747 4.3.4.6 Heartbeat Procedures 4749 The optional Heartbeat procedures MAY be used when operating over 4750 transport layers that do not have their own heartbeat mechanism for 4751 detecting loss of the transport association (i.e., other than SCTP). 4753 Either SUA peer may optionally send Heartbeat messages periodically, 4754 subject to a provisionable timer T(beat). Upon receiving a Heartbeat 4755 message, the SUA peer MUST respond with a Heartbeat Ack message. 4757 If no Heartbeat Ack message (or any other SUA message) is received 4758 from the SUA peer within 2*T(beat), the remote SUA peer is considered 4759 unavailable. Transmission of Heartbeat messages is stopped and the 4760 signalling process SHOULD attempt to re-establish communication if it 4761 is configured as the client for the disconnected SUA peer. 4763 The Heartbeat message may optionally contain an opaque Heartbeat Data 4764 parameter that MUST be echoed back unchanged in the related Heartbeat 4765 Ack message. The sender, upon examining the contents of the returned 4766 Heartbeat Ack message, MAY choose to consider the remote SUA peer as 4767 unavailable. The contents/format of the Heartbeat Data parameter is 4768 implementation-dependent and only of local interest to the original 4769 sender. The contents may be used, for example, to support a 4770 Heartbeat sequence algorithm (to detect missing Heartbeats), and/or a 4771 timestamp mechanism (to evaluate delays). 4773 Note: Heartbeat related events are not shown in Figure 4 "ASP state 4774 transition diagram". 4776 4.4 Routing Key Management Procedures 4778 4.4.1 Registration 4780 An ASP MAY dynamically register with an SGP as an ASP within an 4781 Application Server using the REG REQ message. A Routing Key parameter 4782 in the REG REQ message specifies the parameters associated with the 4783 Routing Key. 4785 The SGP examines the contents of the received Routing Key parameter 4786 and compares it with the currently provisioned Routing Keys. If the 4787 received Routing Key matches an existing SGP Routing Key entry, and 4788 the ASP is not currently included in the list of ASPs for the related 4789 Application Server, the SGP MAY authorize the ASP to be added to the 4790 AS. Or, if the Routing Key does not currently exist and the received 4791 Routing Key data is valid and unique, an SGP supporting dynamic 4792 configuration MAY authorize the creation of a new Routing Key and 4793 related Application Server and add the ASP to the new AS. In either 4794 case, the SGP returns a Registration Response message to the ASP, 4795 containing the same Local-RK-Identifier as provided in the initial 4796 request, and a Registration Result "Successfully Registered". A 4797 unique Routing Context value assigned to the SGP Routing Key is 4798 included. The method of Routing Context value assignment at the SGP 4799 is implementation dependent but must be guaranteed to be unique for 4800 each Application Server or Routing Key supported by the SGP. If the 4801 SGP determines that the received Routing Key data is invalid, or 4802 contains invalid parameter values, the SGP returns a Registration 4803 Response message to the ASP, containing a Registration Result "Error 4804 - Invalid Routing Key", "Error - Invalid DPC", "Error - Invalid 4805 Network Appearance" as appropriate. 4807 If the SGP does not support the registration procedure, the SGP 4808 returns an Error message to the ASP, with an error code of 4809 "Unsupported Message Type". 4811 If the SGP determines that a unique Routing Key cannot be created, 4812 the SGP returns a Registration Response message to the ASP, with a 4813 Registration Status of "Error - "Cannot Support Unique Routing." An 4814 incoming signalling message received at an SGP should not match 4815 against more than one Routing Key. 4817 If the SGP does not authorize the registration request, the SGP 4818 returns a REG RSP message to the ASP containing the Registration 4819 Result "Error - Permission Denied". 4821 If an SGP determines that a received Routing Key does not currently 4822 exist and the SGP does not support dynamic configuration, the SGP 4823 returns a Registration Response message to the ASP, containing a 4824 Registration Result "Error - Routing Key not Currently Provisioned". 4826 If an SGP determines that a received Routing Key does not currently 4827 exist and the SGP supports dynamic configuration but does not have 4828 the capacity to add new Routing Key and Application Server entries, 4829 the SGP returns a Registration Response message to the ASP, 4830 containing a Registration Result "Error - Insufficient Resources". 4832 If an SGP determines that one or more of the Routing Key parameters 4833 are not supported for the purpose of creating new Routing Key 4834 entries, the SGP returns a Registration Response message to the ASP, 4835 containing a Registration Result "Error - Unsupported RK parameter 4836 field". This result MAY be used if, for example, the SGP does not 4837 support RK Address parameter. 4839 A Registration Response "Error - Unsupported Traffic Handling Mode" 4840 is returned if the Routing Key in the REG REQ contains a Traffic 4841 Handling Mode that is inconsistent with the presently configured mode 4842 for the matching Application Server. 4844 An ASP MAY register multiple Routing Keys at once by including a 4845 number of Routing Key parameters in a single REG REQ message. The 4846 SGP MAY respond to each registration request in a single REG RSP 4847 message, indicating the success or failure result for each Routing 4848 Key in a separate Registration Result parameter. Alternatively the 4849 SGP MAY respond with multiple REG RSP messages, each with one or more 4850 Registration Result parameters. The ASP uses the Local-RK-Identifier 4851 parameter to correlate the requests with the responses. 4853 An ASP MAY modify an existing Routing Key by including a Routing 4854 Context parameter in the REG REQ. If the SGP determines that the 4855 Routing Context applies to an existing Routing Key, the SG MAY adjust 4856 the existing Routing Key to match the new information provided in the 4857 Routing Key parameter. A Registration Response "Routing Key Change 4858 Refused" is returned if the SGP does not accept the modification of 4859 the Routing Key. 4861 Upon successful registration of an ASP in an AS, the SGP can now send 4862 related SS7 Signalling Network Management messaging, if this did not 4863 previously start upon the ASP transitioning to state ASP-INACTIVE 4865 4.4.2 Deregistration 4867 An ASP MAY dynamically deregister with an SGP as an ASP within an 4868 Application Server using the DEREG REQ message. A Routing Context 4869 parameter in the DEREG REQ message specifies which Routing Keys to 4870 de-register. An ASP SHOULD move to the ASP-INACTIVE state for an 4871 Application Server before attempting to deregister the Routing Key 4872 (i.e., deregister after receiving an ASP Inactive Ack). Also, an ASP 4873 SHOULD deregister from all Application Servers that it is a member 4874 before attempting to move to the ASP-Down state. 4876 The SGP examines the contents of the received Routing Context 4877 parameter and validates that the ASP is currently registered in the 4878 Application Server(s) related to the included Routing Context(s). If 4879 validated, the ASP is de-registered as an ASP in the related 4880 Application Server. 4882 The deregistration procedure does not necessarily imply the deletion 4883 ofRouting Key and Application Server configuration data at the SGP. 4884 Other ASPs may continue to be associated with the Application Server, 4885 in which case the Routing Key data SHOULD NOT be deleted. If a 4886 Deregistration results in no more ASPs in an Application Server, an 4887 SGP MAY delete the Routing Key data. 4889 The SGP acknowledges the deregistration request by returning a DEREG 4890 RSP message to the requesting ASP. The result of the deregistration 4891 is found in the Deregistration Result parameter, indicating success 4892 or failure with cause. 4894 An ASP MAY deregister multiple Routing Contexts at once by including 4895 a number of Routing Contexts in a single DEREG REQ message. The SGP 4896 MAY respond to each deregistration request in a single DEREG RSP 4897 message, indicating the success or failure result for each Routing 4898 Context in a separate Deregistration Result parameter. 4900 4.4.3 IPSP Considerations (REG/DEREG) 4902 The Registration/Deregistration procedures work in the IPSP cases in 4903 the same way as in AS-SG cases. An IPSP may register an RK in the 4904 remote IPSP. An IPSP is responsible for deregistering the RKs that 4905 it has registered. 4907 4.5 Availability and/or Congestion Status of SS7 Destination Support 4909 4.5.1 At an SGP 4911 On receiving a N-STATE, N-PCSTATE and N-INFORM indication primitive 4912 from the nodal inter-working function at an SGP, the SGP SUA layer 4913 will send a corresponding SS7 Signalling Network Management (SNM) 4914 DUNA, DAVA, SCON, or DUPU message (see Section 3.4) to the SUA peers 4915 at concerned ASPs. The SUA layer must fill in various fields of the 4916 SNM messages consistently with the information received in the 4917 primitives. 4919 The SGP SUA layer determines the set of concerned ASPs to be informed 4920 based on the specific SS7 network for which the primitive indication 4921 is relevant. In this way, all ASPs configured to send/receive traffic 4922 within a particular network appearance are informed. If the SGP 4923 operates within a single SS7 network appearance, then all ASPs are 4924 informed. 4926 DUNA, DAVA, SCON, and DRST messages are sent sequentially and 4927 processed at the receiver in the order sent. SCTP stream 0 SHOULD 4928 NOT be used. The Unordered bit in the SCTP DATA chunk MAY be used for 4929 the SCON message. 4931 Sequencing is not required for the DUPU or DAUD messages, which MAY 4932 be sent un-sequenced. SCTP stream 0 is used, with optional use of 4933 the Unordered bit in the SCTP DATA chunk. 4935 4.5.2 At an ASP 4937 4.5.2.1 Single SG Configurations 4938 At an ASP, upon receiving an SS7 Signalling Network Management (SSNM) 4939 message from the remote SUA Peer, the SUA layer invokes the 4940 appropriate primitive indications to the resident SUA-Users. Local 4941 management is informed. 4943 In the case where a local event has caused the unavailability or 4944 congestion status of SS7 destinations, the SUA layer at the ASP 4945 SHOULD pass up appropriate indications in the primitives to the SUA 4946 User, as though equivalent SSNM messages were received. For example, 4947 the loss of an SCTP association to an SGP may cause the 4948 unavailability of a set of SS7 destinations. N-PCSTATE indication 4949 primitives to the SUA User are appropriate. 4951 Implementation Note: To accomplish this, the SUA layer at an ASP 4952 maintains the status of routes via the SG. 4954 4.5.2.2 Multiple SG Configurations 4956 At an ASP, upon receiving a Signalling Network Management message 4957 from the remote SUA Peer, the SUA layer updates the status of the 4958 affected route(s) via the originating SG and determines, whether or 4959 not the overall availability or congestion status of the effected 4960 destination(s) has changed. If so, the SUA layer invokes the 4961 appropriate primitive indications to the resident SUA-Users. Local 4962 management is informed. 4964 4.5.3 ASP Auditing 4966 An ASP may optionally initiate an audit procedure to enquire of an 4967 SGP the availability and, if the national congestion method with 4968 multiple congestion levels and message priorities is used, congestion 4969 status of an SS7 destination or set of destinations. A Destination 4970 Audit (DAUD) message is sent from the ASP to the SGP requesting the 4971 current availability and congestion status of one or more SS7 4972 destinations or subsystems. 4974 The DAUD message MAY be sent un-sequenced. The ASP MAY send the DAUD 4975 in the following cases: 4977 - Periodic. A Timer originally set upon reception of a DUNA, 4978 SCON or DRST message has expired without a 4979 subsequent DAVA, DUNA, SCON or DRST message updating 4980 the availability/congestion status of the affected 4981 Destination Point Code. The Timer is reset upon 4982 issuing a DAUD. In this case the DAUD is sent to 4983 the SGP that originally sent the SSNM message. 4985 - Isolation. The ASP is newly ASP-ACTIVE or has been isolated 4986 from an SGP for an extended period. The ASP MAY 4987 request the availability/congestion status of one or 4988 more SS7 destinations to which it expects to 4989 communicate. 4991 Implementation Note: 4993 In the first of the cases above, the auditing procedure must not 4994 be invoked for the case of a received SCON message containing a 4995 congestion level value of "no congestion" or undefined" (i.e., 4996 congestion Level = "0"). This is because the value indicates 4997 either congestion abatement or that the ITU MTP3 international 4998 congestion method is being used. In the international congestion 4999 method, the MTP3 layer at the SGP does not maintain the congestion 5000 status of any destinations and therefore the SGP cannot provide 5001 any congestion information in response to the DAUD. For the same 5002 reason, in the second of the cases above a DAUD message cannot 5003 reveal any congested destination(s). 5005 The SGP SHOULD respond to a DAUD message with the availability and 5006 congestion status of the subsystem. The status of each SS7 5007 destination or subsystem requested is indicated in a DUNA message (if 5008 unavailable), a DAVA message (if available), or a DRST (if restricted 5009 and the SGP supports this feature). If the SS7 destination or 5010 subsystem is available and congested, the SGP responds with an SCON 5011 message in addition to the DAVA message. If the SS7 destination or 5012 subsystem is restricted and congested, the SGP responds with an SCON 5013 message in addition to the DRST. If the SGP has no information on 5014 the availability / congestion status of the SS7 destination or 5015 subsystem, the SGP responds with a DUNA message, as it has no routing 5016 information to allow it to route traffic to this destination or 5017 subsystem. 5019 An SG MAY refuse to provide the availability or congestion status of 5020 a destination or subsystem if, for example, the ASP is not authorized 5021 to know the status of the destination or subsystem. The SG MAY 5022 respond with an Error Message (Error Code = "Destination Status 5023 Unknown") or Error Message (Error Code = "Subsystem Status Unknown"). 5025 4.6 MTP3 Restart 5027 In the case where the MTP3 in the SG undergoes an MTP restart, event 5028 communication SHOULD be handled as follows: 5030 When the SG discovers SS7 network isolation, the SGPs send an 5031 indication to all concerned available ASPs (i.e., ASPs in the ASP- 5032 ACTIVE state) using DUNA messages for the concerned destinations. 5033 When the SG has completed the MTP Restart procedure, the SUA layer 5034 at the SGPs inform all concerned ASPs in the ASP-ACTIVE state of any 5035 available/restricted SS7 destinations using the DAVA/DRST message. 5036 No message is necessary for those destinations still unavailable 5037 after the restart procedure. 5039 When the SUA layer at an ASP receives a DUNA message indicating SS7 5040 destination unavailability at an SG, Users will stop any affected 5041 traffic to this destination. When the SUA layer receives a DAVA/DRST 5042 message, Users can resume traffic to the newly available SS7 5043 destination via this SGP, provided the ASP is in the ASP-ACTIVE 5044 state towards this SGP. 5046 The ASP MAY choose to audit the availability of unavailable 5047 destinations by sending DAUD messages. This would be for example the 5048 case when an AS becomes active at an ASP and does not have up to 5049 date destination statuses. If MTP restart is then in progress at 5050 the SG, the SGP returns a DUNA message for that destination, even if 5051 it received an indication that the destination became available or 5052 restricted. 5054 4.7 SCCP - SUA Interworking at the SG 5056 4.7.1 Segmenting / Reassembly 5058 When it is expected that signalling messages will not fit into a PDU 5059 of the most restrictive transport technology used (e.g. 272-SIF of 5060 MTP3), then segmenting/reassembly could be performed at the SG, ASP 5061 or IPSP. If the SG, ASP or IPSP is incapable of performing a 5062 necessary segmentation/reassembly, it can inform the peer of the 5063 failure using the appropriate error in a CLDR or RESRE/COERR message. 5065 4.7.2 Support for Loadsharing 5067 Within an AS (identified by RK/RC parameters) several loadsharing 5068 ASPs may be active. 5070 However, in order to assure the correct processing of TCAP 5071 transactions or SCCP connections, the loadsharing scheme used at the 5072 SG must make sure that messages continuing or ending the 5073 ransactions/connections arrive at the same ASP where the initial 5074 message (TC_Query, TC_Begin, CR) was sent to/received from. 5076 When the ASP can be identified uniquely based on RK parameters (e.g. 5077 unique DPC or GT), loadsharing is not required. When the ASPs in the 5078 AS share state or use an internal distribution mechanism, the SG must 5079 only take into account the in-sequence-delivery requirement. In case 5080 of SCCP CO traffic, when the coupled approach is used, loadsharing of 5081 messages other than CR is not required. 5083 If these assumptions cannot be made, both SG and ASP should support 5084 the following general procedure in a loadsharing environment. 5086 4.7.2.1 Association Setup, ASP going active 5088 After association setup and registration, an ASP normally goes active 5089 for each AS it registered for. In the ASPAC message, the ASP includes 5090 a TID and/or DRN Label Parameter, if applicable for the AS in 5091 question. All the ASPs within the AS must specify a unique label at a 5092 fixed position in the TID or DRN parameter. The same ASPAC message is 5093 sent to each SG used for interworking with the SS7 network. 5095 The SG builds, per RK, a list of ASPs that have registered for it. 5096 The SG can now build up and update a distribution table for a certain 5097 Routing Context, any time the association is (re-)established and the 5098 ASP goes active. The SG has to perform some trivial plausibility 5099 checks on the parameters: 5101 - Start and End parameters values are between 0 and 31 for TID. 5102 - Start and End parameters values are between 0 and 23 for DRN 5103 - 0 < (Start - End + 1) <= 16 (label length maximum 16-bit) 5104 - Start values are the same for each ASP within a RC 5105 - End values are the same for each ASP within a RC 5106 - TID and DRN Label values must be unique across the RC 5108 If any of these checks fail, the SG refuses the ASPAC request, with 5109 an error, "Invalid loadsharing label." 5111 4.7.3 Routing and message distribution at the SG 5113 4.7.3.1 TCAP traffic 5115 Messages not containing a destination (or "responding") TID, i.e. 5116 Query, Begin, Unidirectional, are loadshared among the available 5117 ASPs. Any scheme permitting a fair load distribution among the ASPs 5118 is allowed (e.g. round robin). 5120 When a destination TID is present, the SG extracts the label and 5121 selects the ASP that corresponds with it. 5123 If an ASP is not available, the SG may generate (X)UDTS "routing 5124 failure", if the return option is used. 5126 4.7.3.2 SCCP Connection Oriented traffic 5128 Messages not containing a destination reference number (DRN), i.e. a 5129 Connection Request, MAY be loadshared among the available ASPs. The 5130 load distribution mechanism is an implementation issue. When a DRN is 5131 present, the SG extracts the label and selects the ASP that 5132 corresponds with it. If an ASP is not available, the SG discards the 5133 message. 5135 4.7.4 Multiple SGs, SUA Relay Function 5137 It is important that each ASP send its unique label (within the AS) 5138 to each SGP. For a better robustness against association failures, 5139 the SGs MAY cooperate to provide alternative routes towards an ASP. 5141 Mechanisms for SG cooperation/co-ordination are outside of the scope 5142 of this document. 5144 5 Examples of SUA Procedures 5146 The following sequence charts overview the procedures of SUA. These 5147 are meant as examples, they do not, in and of themselves, impose 5148 additional requirements upon an instance of SUA. 5150 5.1 SG Architecture 5152 The sequences below outline logical steps for a variety of scenarios 5153 within a SG architecture. Please note that these scenarios cover a 5154 Primary/Backup configuration. Where there is a load-sharing 5155 configuration then the SGP can declare availability when 1 ASP 5156 issues ASPAC but can only declare unavailability when all ASPs have 5157 issued ASPIA. 5159 5.1.1 Establishment of SUA connectivity 5161 The following is established before traffic can flow. 5163 Each node is configured (via MIB, for example) with the connections 5164 that need to be setup. 5166 ASP-a1 ASP-a2 SG SEP 5167 (Primary) (Backup) 5168 |------Establish SCTP Association------| 5169 |--Estab. SCTP Ass--| 5170 |--Align SS7 link---| 5171 +----------------ASP Up----------------> 5172 <--------------ASP Up Ack--------------+ 5173 +------ASP Up-------> 5174 <---ASP Up Ack------+ 5175 +-------------ASP Active---------------> 5176 <----------ASP Active Ack--------------+ 5177 <----------NTFY (ASP Active)-----------+ 5178 <-NTFY (ASP Active)-+ 5179 +--------SSA--------> 5180 <--------SSA--------+ 5181 <-----------------DAVA-----------------+ 5182 +-----------------CLDT-----------------> 5183 +--------UDT--------> 5185 5.1.2 Failover scenarios 5187 The following sequences address failover of SEP and ASP 5189 5.1.2.1 SEP Failover 5190 The SEP knows that the SGP is 'concerned' about its availability. 5191 Similarly, the SGP knows that ASP-a1 is concerned about the SEPs 5192 availability. 5194 ASP-a1 ASP-a2 SG SEP 5195 (Primary) (Backup) 5196 <--------SSP--------+ 5197 <-----------------DUNA-----------------+ 5198 +-----------------DAUD-----------------> 5199 +--------SST--------> 5201 5.1.2.2 Successful ASP Failover scenario 5203 The following is an example of a successful failover scenario, where 5204 there is a failover from ASP-a1 to ASP-a2, i.e. Primary to Backup. 5205 During the failover, the SGP buffers any incoming data messages from 5206 the SEP, forwarding them when the Backup becomes available. 5208 ASP-a1 ASP-a2 SG SEP 5209 (Primary) (Backup) 5210 +-------------ASP Inactive-------------> 5211 <-----------ASP Inactive ACK-----------+ 5212 <--------------------NTFY (AS Pending)-+ 5213 <-NTFY (AS Pending)-+ 5214 +----ASP Active-----> 5215 <--ASP Active Ack---+ 5216 <-NTFY (AS Active)--+ 5217 <----------NTFY (AS Active)------------+ 5219 5.1.2.3 Unsuccessful ASP Failover scenario 5221 ASP-a1 ASP-a2 SG SEP 5222 (Primary) (Backup) 5223 +-------------ASP Inactive-------------> 5224 <-----------ASP Inactive ACK-----------+ 5225 <--------------------NTFY (AS Pending)-+ 5226 <--NTFY (AS Pending)-+ 5227 After some time elapses (i.e. timeout). 5228 +--------SSP--------> 5229 <--------SST--------+ 5230 <-------------------NTFY (AS Inactive)-+ 5231 <-NTFY (AS Inactive)-+ 5233 5.2 IPSP Examples. 5235 The sequences below outline logical steps for a variety of scenarios 5236 within an IP-IP architecture. Please note that these scenarios 5237 cover a Primary/Backup configuration. Where there is a load-sharing 5238 configuration then the AS can declare availability when 1 ASP issues 5239 ASPAC but can only declare unavailability when all ASPs have issued 5240 ASPIA. 5242 5.2.1 Establishment of SUA connectivity 5244 The following shows an example establishment of SUA connectivity. 5245 In this example, each IPSP consists of an Application Server and two 5246 ASPs. The following is established before SUA traffic can flow. A 5247 connectionless flow is shown for simplicity. 5249 Establish SCTP Connectivity - as per RFC 2960. Note that SCTP 5250 connections are bi-directional. The endpoint that establishes SCTP 5251 connectivity MUST also establishes UA connectivity (see RFC 2960, 5252 section 5.2.1 for handling collisions) [2960]. 5254 IP SEP A IP SEP B 5255 AS A AS B 5256 ASP-a1 ASP-a2 ASP-b2 ASP-b1 5258 [All ASPs are in the ASP-DOWN state] 5260 +-------------------------------ASP Up--------------------------> 5261 <-----------------------------ASP Up Ack------------------------+ 5263 +--------------ASP Up---------------> 5264 <------------ASP Up Ack-------------+ 5266 +---------------------------ACTIVE-------------------------------> 5267 <-------------------------ACTIVE Ack-----------------------------+ 5269 [Traffic can now flow directly between ASPs] 5271 +-----------------------------CLDT-------------------------------> 5273 5.2.2 Failover scenarios 5275 The following sequences address failover of ASP 5277 5.2.2.1 Successful ASP Failover scenario 5279 The following is an example of a successful failover scenario, where 5280 there is a failover from ASP-a1 to ASP-a2, i.e. Primary to Backup. 5281 Since data transfer passes directly between peer ASPs, ASP-b1 is 5282 notified of the failover of ASP-a1 and buffers outgoing data 5283 messages until ASP-a2 becomes available. 5285 IP SEP A IP SEP B 5286 ASP-a1 ASP-a2 ASP-b2 ASP-b1 5288 +-----------------------------ASP Inact------------------------> 5289 <---------------------------ASP Inact Ack----------------------+ 5290 <---------------NTFY (ASP-a1 Inactive)--------------+ 5291 +---------------------ASP Act-----------------------> 5292 <-------------------ASP Act Ack---------------------+ 5294 5.2.2.2 Unsuccessful ASP Failover scenario 5296 The sequence is the same as 5.2.2.1 except that, since the backup 5297 fails to come in then, the Notify messages declaring the 5298 availability of the backup are not sent. 5300 6 Security Considerations 5302 The security considerations discussed for the 'Security 5303 Considerations for SIGTRAN Protocols' [SIGSEC] document apply to 5304 this document. 5306 7 IANA Considerations 5308 7.1 SCTP Payload Protocol ID 5310 IANA has assigned a SUA value for the Payload Protocol Identifier in 5311 the SCTP DATA chunk. The following SCTP Payload Protocol Identifier 5312 is registered: 5314 SUA "4" 5316 The SCTP Payload Protocol Identifier value "4" SHOULD be included in 5317 each SCTP DATA chunk, to indicate that the SCTP is carrying the SUA 5318 protocol. The value "0" (unspecified) is also allowed but any other 5319 values MUST not be used. This Payload Protocol Identifier is not 5320 directly used by SCTP but MAY be used by certain network entities to 5321 identify the type of information being carried in a DATA chunk. 5323 The User Adaptation peer MAY use the Payload Protocol Identifier, as 5324 a way of determining additional information about the data being 5325 presented to it by SCTP. 5327 7.2 Port Number 5329 IANA has registered SCTP Port Number 14001 for SUA. It is 5330 recommended that SGPs use this SCTP port number for listening for 5331 new connections. SGPs MAY also use statically configured SCTP port 5332 numbers instead. 5334 7.3 Protocol Extensions 5336 This protocol may also be extended through IANA in three ways: 5338 - Through definition of additional message classes. 5339 - Through definition of additional message types. 5340 - Through definition of additional message parameters. 5342 The definition and use of new message classes, types and parameters 5343 is an integral part of SIGTRAN adaptation layers. Thus, these 5344 extensions are assigned by IANA through an IETF Consensus action as 5345 defined in [RFC2434]. 5347 The proposed extension MUST in no way adversely affect the general 5348 working of the protocol. 5350 A new registry will be created by IANA to allow the protocol to be 5351 extended 5353 7.3.1 IETF Defined Message Classes 5355 The documentation for a new message class MUST include the following 5356 information: 5358 (a) A long and short name for the message class; 5359 (b) A detailed description of the purpose of the message class. 5361 7.3.2 IETF Defined Message Types 5363 Documentation of the message type MUST contain the following 5364 information: 5366 (a) A long and short name for the new message type; 5367 (b) A detailed description of the structure of the message. 5368 (c) A detailed definition and description of intended use of each 5369 field within the message. 5370 (d) A detailed procedural description of the use of the new message 5371 type within the operation of the protocol. 5372 (e) A detailed description of error conditions when receiving this 5373 message type. 5375 When an implementation receives a message type which it does not 5376 support, it MUST respond with an Error (ERR) message, with an Error 5377 Code = Unsupported Message Type. 5379 7.3.4 IETF-defined TLV Parameter Extension 5381 Documentation of the message parameter MUST contain the following 5382 information: 5384 (a) Name of the parameter type. 5385 (b) Detailed description of the structure of the parameter field. 5386 This structure MUST conform to the general type-length-value 5387 format described earlier in the document. 5388 (c) Detailed definition of each component of the parameter value. 5389 (d) Detailed description of the intended use of this parameter type, 5390 and an indication of whether and under what circumstances 5391 multiple instances of this parameter type may be found within 5392 the same message type. 5394 8 Timer Values 5396 Ta 2 seconds 5397 Tr 2 seconds 5398 T(ack) 2 seconds 5399 T(ias) Inactivity Send timer 7 minutes 5400 T(iar) Inactivity Receive timer 15 minutes 5401 T(beat) Heartbeat Timer 30 seconds 5403 9 Acknowledgements 5405 The authors would like to thank (in alphabetical order) Richard 5406 Adams, Javier Pastor-Balbas, Andrew Booth, Martin Booyens, F. 5407 Escobar, S. Furniss 5408 Klaus Gradischnig, Miguel A. Garcia, Marja-Liisa Hamalainen, Sherry 5409 Karl, S. Lorusso, Markus Maanoja, Sandeep Mahajan, Ken Morneault, 5410 Guy Mousseau, Chirayu Patel, Michael Purcell, W. Sully, Michael 5411 Tuexen, Al Varney, Tim Vetter, Antonio Villena, Ben Wilson, Michael 5412 Wright and James Yu for their insightful comments and suggestions. 5414 10 Authors' Addresses 5416 John Loughney 5417 Nokia Research Center 5418 PO Box 407 5419 FIN-00045 Nokia Group 5420 Finland 5421 EMail: john.Loughney@nokia.com 5423 Greg Sidebottom 5424 gregside consulting 5425 Kanata, Ontario 5426 Canada 5427 EMail: gregside@home.com 5429 Lode Coene 5430 Siemens Atea 5431 Atealaan 34 5432 B-2200 Herentals 5433 Belgium 5434 Phone: +32-14-252081 5435 EMail: lode.coene@siemens.atea.be 5437 Gery Verwimp 5438 Siemens Atea 5439 34 Atealaan 5440 PO 2200 5441 Herentals 5442 Belgium 5443 Phone: +32 14 25 3424 5444 EMail: gery.verwimp@siemens.atea.be 5446 Joe Keller 5447 Tekelec 5448 5200 Paramount Parkway 5449 Morrisville, NC 27560 5450 USA 5451 EMail: joe.keller@tekelec.com 5453 Brian Bidulock 5454 OpenSS7 Corporation 5455 4701 Preston Park Boulevard 5456 Suite 424 5457 Plano TX 75093 5458 USA 5459 EMail: bidulock@openss7.org 5461 11 References 5463 11.1 Normative 5465 [1123] RFC 1123, "Requirements for Internet Hosts -- 5466 Application and Support" Braden, R. (Editor), October 5467 1989. 5469 [2279] RFC 2279, "UTF-8, a transformation format of ISO 5470 10646", January 1998. 5472 [2960] RFC 2960 "Stream Control Transmission Protocol", R. 5473 Stewart, et al, November 2000. 5475 [ANSI SCCP] ANSI T1.112 "Signalling System Number 7 - Signalling 5476 Connection Control Part". 5478 [ITU SCCP] ITU-T Recommendations Q.711-714, "Signalling System 5479 No. 7 (SS7) - Signalling Connection Control Part 5480 (SCCP)." ITU-T Telecommunication Standardization 5481 Sector of ITU, formerly CCITT, Geneva (July 1996). 5483 [SIGSEC] J. Loughney, M. Tuexen, J. Pastor-Balbas, "Security 5484 Considerations for SIGTRAN Protocols", Work in 5485 Progress. 5487 11.2 Non-Normative 5489 [2434] RFC 2434, "Guidelines for Writing an IANA 5490 Considerations Section in RFCs", T. Narten, H. 5491 Alvestrand, October 1998. 5493 [2719] RFC 2719, "Framework Architecture for Signalling 5494 Transport." 5496 [2916] RFC 2916, "E.164 number and DNS', P. Faltstrom, 5497 September 2000. 5499 [ANSI-MTP] ANSI T1.111 'Signalling System Number 7 - Message 5500 Transfer Part' 5502 [ANSI TCAP] ANSI T1.114 'Signalling System Number 7 - Transaction 5503 Capabilities Application Part' 5505 [ITU-MTP] ITU-T Recommendations Q.701-Q.705, 'Signalling System 5506 No. 7 (SS7) - Message Transfer Part (MTP).' 5508 [ITU TCAP] ITU-T Recommendation Q.771-775 'Signalling System No. 5509 7 SS7) - Transaction Capabilities (TCAP).' 5511 [M3UA] RFC 3332, "MTP3-User Adaptation Layer", G. 5512 Sidebottom, et al., September 2002. 5514 [RANAP] 3G TS 25.413 V3.5.0 (2001-03) 'Technical 5515 Specification 3rd Generation Partnership Project; 5516 Technical Specification Group Radio Access Network; 5517 UTRAN Iu Interface RANAP Signalling' 5519 [UTRAN IUR] 3G TS 25.422 V3.5.0 (2000-12) 'Technical 5520 Specification 3rd Generation Partnership Project; 5521 Technical Specification Group Radio Access Network; 5522 UTRAN Iur Interface Signalling Transport (Release 5523 1999).' 5525 Appendix A Signalling Network Architecture 5527 A.1 Generalized Peer-to-Peer Network Architecture 5529 Figure 1 shows an example network architecture that can support 5530 robust operation and failover. There need to be some management 5531 resources at the AS to manage traffic. 5533 *********** 5534 * AS1 * 5535 * +-----+ * SCTP Associations 5536 * |ASP1 +-------------------+ 5537 * +-----+ * | *********** 5538 * * | * AS3 * 5539 * +-----+ * | * +-----+ * 5540 * |ASP2 +-----------------------------------------+ASP1 | * 5541 * +-----+ * | * +-----+ * 5542 * * | * * 5543 * +-----+ * | * +-----+ * 5544 * |ASP3 | * +--------------------------+ASP2 | * 5545 * +-----+ * | | * +-----+ * 5546 *********** | | *********** 5547 | | 5548 *********** | | *********** 5549 * AS2 * | | * AS4 * 5550 * +-----+ * | | * +-----+ * 5551 * |ASP1 +--------------+ +---------------------+ASP1 | * 5552 * +-----+ * * +-----+ * 5553 * * * * 5554 * +-----+ * * +-----+ * 5555 * |ASP2 +-----------------------------------------+ASP1 | * 5556 * +-----+ * * +-----+ * 5557 * * *********** 5558 * +-----+ * 5559 * |ASP3 | * 5560 * +-----+ * 5561 * * 5562 *********** 5564 Figure 1: Generalized Architecture 5566 In this example, the Application Servers are shown residing within 5567 one logical box, with ASPs located inside. In fact, an AS could be 5568 distributed among several hosts. In such a scenario, the host 5569 should share state as protection in the case of a failure. This is 5570 out of scope of this protocol. Additionally, in a distributed 5571 system, one ASP could be registered to more than one AS. This draft 5572 should not restrict such systems - though such a case in not 5573 specified. 5575 A.2 Signalling Gateway Network Architecture 5577 When interworking between SS7 and IP domains is needed, the SGP acts 5578 as the gateway node between the SS7 network and the IP network. The 5579 SGP will transport SCCP-user signalling traffic from the SS7 network 5580 to the IP-based signalling nodes (for example IP-resident 5581 Databases). The Signalling Gateway can be considered as a group of 5582 Application Servers with additional functionality to interface 5583 towards an SS7 network. 5585 The SUA protocol should be flexible enough to allow different 5586 configurations and transport technology to allow the network 5587 operators to meet their operation, management and performance 5588 requirements. 5590 An ASP may be connected to multiple SGPs (see figure 2). In such a 5591 case, a particular SS7 destination may be reachable via more than 5592 SG, therefore, more than one route. Given that proper SLS selection, 5593 loadsharing, and SG selection based on point code availability is 5594 performed at the ASP, it will be necessary for the ASP to maintain 5595 the status of each distant SGPs to which it communicates on the 5596 basis of the SG through which it may route. 5598 Signalling Gateway 5599 SCTP Associations 5600 +----------+ ************** 5601 | SG1 | * AS3 * 5602 | ******** | * ******** * 5603 | * SGP11+--------------------------------------------+ ASP1 * * 5604 | ******** | / * ******** * 5605 | ******** | | * ******** * 5606 | * SGP12+--------------------------------------------+ ASP2 * * 5607 | ******** | \ / | * ******** * 5608 +----------+ \ | | * . * 5609 \ | | * . * 5610 +---------- \ | | * . * 5611 | SG2 | \ | | * . * 5612 | ******** | \ | | * ******** * 5613 | * SGP21+---------------------------------+-* * ASPN * * 5614 | ******** | \ * ******** * 5615 | ******** | \ ************** 5616 | * SGP22+---+--+ \ 5617 | ******** | | | \ ************** 5618 +----------+ | | \ * AS4 * 5619 | | \ * ******** * 5620 | +-------------------------------------+ ASP1 * * 5621 | * ******** * 5622 | * . * 5623 | * . * 5624 | * * 5625 | * ******** * 5626 +----------------------------------------+ ASPn * * 5627 * ******** * 5628 ************** 5630 Figure 2: Signalling Gateway Architecture 5632 The pair of SGs can either operate as replicated endpoints or as 5633 replicated relay points from the SS7 network point of view. 5635 Replicated endpoints: the coupling between the SGs and the ASPs when 5636 the SGs act as replicated endpoints is an implementation issue. 5638 Replicated relay points: in normal circumstances, the path from SEP 5639 to ASP will always go via the same SGP when in-sequence-delivery is 5640 requested. However, linkset failures may cause MTP to re-route to 5641 the other SG. 5643 A.3 Signalling Gateway Message Distribution Recommendations 5645 A.3.1 Connectionless Transport 5647 By means of configuration, the SG knows the local SCCP-user is 5648 actually represented by an AS, and serviced by a set of ASPs working 5649 in n+k redundancy mode. An ASP is selected and a CLDT message is 5650 sent on the appropriate SCTP association/stream. 5652 The selection criterion can be based on a round robin mechanism, or 5653 any other method that guarantees a balanced load sharing over the 5654 active ASPs. However, when TCAP messages are transported, load 5655 sharing is only possible for the first message in a TCAP dialogue 5656 (TC_Begin, TC_Query, TC_Unidirectional). All other TCAP messages in 5657 the same dialogue are sent to the same ASP that was selected for the 5658 first message, unless the ASPs are able to share state and maintain 5659 in sequence delivery. To this end, the SGP needs to know the TID 5660 allocation policy of the ASPs in a single AS: 5662 - State sharing 5663 - Fixed range of TIDs per ASP in the AS 5665 This information may be preconfigured in the SG, or may be 5666 dynamically exchanged via the ASP_Active message. 5668 An example for an INAP/TCAP message exchange between SEP and ASP is 5669 given below. 5671 Address information in CLDT message (e.g. TC_Query) from SGP to ASP, 5672 with association ID = SG-ASP, Stream ID based on sequence control 5673 and possibly other parameters, e.g. OPC: 5675 - Routing Context: based on SS7 Network ID and AS membership, so 5676 that the message can be transported to the correct ASP. 5677 - Source address: valid combination of SSN, PC and GT, as needed 5678 for back routing to the SEP. 5679 - Destination address: at least SSN, to select the SCCP/SUA-user 5680 at the ASP. 5682 Address information in CLDT message (e.g. TC_Response) from ASP to 5683 SG, with association ID = ASP-SG, stream ID selected by 5684 implementation dependent means with regards to in-sequence-delivery: 5686 - Routing Context: as received in previous message. 5687 - Source address: unique address provided so that when used as 5688 the SCCP called party address in the SEP, it must yield the 5689 same AS, the SSN might be sufficient. 5690 - Destination address: copied from source address in received 5691 CLDT message. 5693 Further messages from the SEP belonging to the same TCAP transaction 5694 will now reach the same ASP. 5696 A.3.2 Connection-Oriented Transport 5698 Further messages for this connection are routed on DPC in the SS7 5699 connection section (MTP routing label), and on IP address in the IP 5700 connection section (SCTP header). No other routing information is 5701 present in the SCCP or SUA messages themselves. Resources are kept 5702 within the SG to forward messages from one section to another and to 5703 populate the MTP routing label or SCTP header, based on the 5704 destination local reference of these messages (Connect Confirm, Data 5705 Transfer, etc.) 5707 This means that in the SG, two local references are allocated, one 5708 3-byte value used for the SS7 section and one 4-byte value for the 5709 IP section. Also a resource containing the connection data for both 5710 sections is allocated, and either of the two local references can be 5711 used to retrieve this data e.g. for an incoming DT1 or CODT, for 5712 example. 5714 Copyright Statement 5716 Copyright (C) The Internet Society (2003). All Rights Reserved. 5718 This document and translations of it may be copied and furnished to 5719 others, and derivative works that comment on or otherwise explain it 5720 or assist in its implementation may be prepared, copied, published 5721 and distributed, in whole or in part, without restriction of any 5722 kind, provided that the above copyright notice and this paragraph 5723 are included on all such copies and derivative works. However, this 5724 document itself may not be modified in any way, such as by removing 5725 the copyright notice or references to the Internet Society or other 5726 Internet organizations, except as needed for the purpose of 5727 developing Internet standards in which case the procedures for 5728 copyrights defined in the Internet Standards process must be 5729 followed, or as required to translate it into languages other than 5730 English. 5732 The limited permissions granted above are perpetual and will not be 5733 revoked by the Internet Society or its successors or assigns. 5735 This document and the information contained herein is provided on an 5736 "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING 5737 TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING 5738 BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION 5739 HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF 5740 MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.