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'1') (Obsoleted by RFC 8077) ** Obsolete normative reference: RFC 4379 (ref. '9') (Obsoleted by RFC 8029) == Outdated reference: A later version (-06) exists of draft-ietf-mpls-tp-oam-requirements-03 == Outdated reference: A later version (-12) exists of draft-ietf-mpls-tp-framework-06 Summary: 5 errors (**), 0 flaws (~~), 13 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 MPLS Working Group M. Bocci 3 Internet-Draft Alcatel-Lucent 4 Intended status: Standards Track G. Swallow 5 Expires: May 14, 2010 Cisco 6 November 10, 2009 8 MPLS-TP Identifiers 9 draft-ietf-mpls-tp-identifiers-00 11 Abstract 13 This document specifies identifiers for MPLS-TP objects. Included 14 are identifiers conformant to existing ITU conventions and 15 identifiers which are compatible with existing IP, MPLS, GMPLS, and 16 Pseudowire definitions. 18 Status of this Memo 20 This Internet-Draft is submitted to IETF in full conformance with the 21 provisions of BCP 78 and BCP 79. 23 Internet-Drafts are working documents of the Internet Engineering 24 Task Force (IETF), its areas, and its working groups. Note that 25 other groups may also distribute working documents as Internet- 26 Drafts. 28 Internet-Drafts are draft documents valid for a maximum of six months 29 and may be updated, replaced, or obsoleted by other documents at any 30 time. It is inappropriate to use Internet-Drafts as reference 31 material or to cite them other than as "work in progress." 33 The list of current Internet-Drafts can be accessed at 34 http://www.ietf.org/ietf/1id-abstracts.txt. 36 The list of Internet-Draft Shadow Directories can be accessed at 37 http://www.ietf.org/shadow.html. 39 This Internet-Draft will expire on May 14, 2010. 41 Copyright Notice 43 Copyright (c) 2009 IETF Trust and the persons identified as the 44 document authors. All rights reserved. 46 This document is subject to BCP 78 and the IETF Trust's Legal 47 Provisions Relating to IETF Documents 48 (http://trustee.ietf.org/license-info) in effect on the date of 49 publication of this document. Please review these documents 50 carefully, as they describe your rights and restrictions with respect 51 to this document. Code Components extracted from this document must 52 include Simplified BSD License text as described in Section 4.e of 53 the Trust Legal Provisions and are provided without warranty as 54 described in the BSD License. 56 Table of Contents 58 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 59 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 60 2. Named Entities . . . . . . . . . . . . . . . . . . . . . . . . 4 61 3. Uniquely Identifying an Operator . . . . . . . . . . . . . . . 5 62 3.1. The Global ID . . . . . . . . . . . . . . . . . . . . . . 5 63 3.2. ITU Carrier Code . . . . . . . . . . . . . . . . . . . . . 5 64 4. Node and Interface Identifiers . . . . . . . . . . . . . . . . 6 65 5. MPLS-TP Tunnel and LSP Identifiers . . . . . . . . . . . . . . 7 66 5.1. MPLS-TP Tunnel Identifiers . . . . . . . . . . . . . . . . 7 67 5.2. MPLS-TP LSP Identifiers . . . . . . . . . . . . . . . . . 7 68 5.3. Mapping to GMPLS Signalling . . . . . . . . . . . . . . . 8 69 6. Pseudowire Path Identifiers . . . . . . . . . . . . . . . . . 8 70 7. Maintenance Identifiers . . . . . . . . . . . . . . . . . . . 9 71 7.1. Maintenance Entity Group Identifiers . . . . . . . . . . . 9 72 7.1.1. ICC based MEG_IDs . . . . . . . . . . . . . . . . . . 9 73 7.1.2. IP Compatible MEG_IDs . . . . . . . . . . . . . . . . 10 74 7.1.2.1. MPLS-TP Tunnel MEG_IDs . . . . . . . . . . . . . . 10 75 7.1.2.2. MPLS-TP LSP MEG_IDs . . . . . . . . . . . . . . . 10 76 7.1.2.3. Pseudowire MEG_IDs . . . . . . . . . . . . . . . . 10 77 7.2. Maintenance Points . . . . . . . . . . . . . . . . . . . . 11 78 7.2.1. Maintenance Point_IDs for MPLS-TP LSPs and Tunnels . . 11 79 7.2.1.1. MPLS-TP Tunnel_MEP_ID . . . . . . . . . . . . . . 11 80 7.2.1.2. MPLS-TP LSP_MEP_ID . . . . . . . . . . . . . . . . 11 81 7.2.1.3. MPLS-TP LSP_MIP_ID . . . . . . . . . . . . . . . . 11 82 7.2.2. Maintenance Identifiers for Pseudowires . . . . . . . 12 83 7.2.2.1. MEP_IDs for PW T-PEs . . . . . . . . . . . . . . . 12 84 7.2.2.2. MP_IDs for Pseudowires . . . . . . . . . . . . . . 12 85 8. Open issues . . . . . . . . . . . . . . . . . . . . . . . . . 13 86 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 87 9.1. Normative References . . . . . . . . . . . . . . . . . . . 13 88 9.2. Informative References . . . . . . . . . . . . . . . . . . 14 89 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15 91 1. Introduction 93 This document specifies identifiers to be used in within the 94 Transport Profile of Multiprotocol Label Switching (MPLS-TP). where 95 compatibility with existing MPLS control plane conventions are 96 necessary. The MPLS-TP requirements [13] require that the elements 97 and objects in an MPLS-TP environment are able to be configured and 98 managed without a control plane. In such an environment many 99 conventions for defining identifiers are possible. In particular, 100 identifiers conformant to existing ITU conventions are defined. It 101 is also anticipated that operational environments where MPLS-TP 102 objects, e.g. Label Switched Paths (LSPs) and Pseudowires (PWs) will 103 be signaled via existing protocols such as the Label Distribution 104 Protocol (RFC 4447) [1] and the Resource Reservation Protocol as it 105 is applied to Generalized Multi-protocol Label Switching (RFCs 3471 & 106 3473) [2][3] (GMPLS). This document defines a set of identifiers for 107 MPLS-TP which are both compatible with those protocols and applicable 108 to MPLS-TP management and OAM functions. 110 1.1. Terminology 112 AII: Attachment Interface Identifier 114 ASN: Autonomous System Number 116 FEC: Forwarding Equivalence Class 118 GMPLS: Generalized Multi-Protocol Label Switching 120 ICC: ITU Carrier Code 122 LSP: Label Switched Path 124 LSR: Label Switching Router 126 ME: Maintenance Entity 128 MEG: Maintenance Entity Group 130 MEP: Maintenance End Point 132 MIP: Maintenance Intermediate Point 134 MPLS: Multi-Protocol Label Switching 136 OAM: Operations, Administration and Maintenance 138 P2MP: Point to Multi-Point 139 P2P: Point to Point 141 PSC: Protection State Coordination 143 PW: Pseudowire 145 RSVP: Resource Reservation Protocol 147 RSVP-TE: RSVP Traffic Engineering 149 S-PE: Switching Provider Edge 151 T-PE: Terminating Provider Edge 153 Requirements Language 155 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 156 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 157 document are to be interpreted as described in RFC 2119 [4]. 159 2. Named Entities 161 In order to configure, operate and manage a transport network based 162 on the MPLS Transport Profile, a number of entities require 163 identification. Identifiers for the follow entities are defined in 164 this document: 166 o Operator 168 * ICC 170 * Global_ID 172 o LSR 174 o LSP 176 o PW 178 o Interface 180 o MEG 182 o MEP 184 o MIP 185 o Tunnel 187 Note that we have borrowed the term tunnel from RSVP-TE (RFC 3209) 188 [5] where it is used to describe an entity that provides an LSP 189 connection between a source and destination LSR which in turn is 190 instantiated by one or more LSPs, where the additional LSPs are used 191 for protection or re-grooming of the tunnel. 193 3. Uniquely Identifying an Operator 195 Two forms of identification are defined, one that is compatible with 196 IP operational practice called a Global_ID and one compatible with 197 ITU practice, the ICC. An Operator MAY be identified either by its 198 Global_ID or by its ICC. 200 3.1. The Global ID 202 RFC 5003 [6] defines a globally unique Attachment Interface 203 Identifier (AII). That AII is composed of three parts, a Global ID 204 which uniquely identifies a operator, a prefix, and finally and 205 attachment circuit identifier. We have chosen to use that Global ID 206 for MPLS-TP. Quoting from RFC 5003, section 3.2, "The global ID can 207 contain the 2-octet or 4-octet value of the operator's Autonomous 208 System Number (ASN). It is expected that the global ID will be 209 derived from the globally unique ASN of the autonomous system hosting 210 the PEs containing the actual AIIs. The presence of a global ID 211 based on the operator's ASN ensures that the AII will be globally 212 unique." 214 When the Global_ID is derived from a 2-octet AS number, the two high- 215 order octets of this 4-octet identifier MUST be set to zero. 217 Note that this Global_ID is used solely to provide a globally unique 218 context for other MPLS-TP identifiers. It has nothing to do with the 219 use of the ASN in protocols such as BGP. 221 3.2. ITU Carrier Code 223 M.1400 defines the ITU Carrier Code (ICC) assigned to a network 224 operator/service provider and maintained by the ITU-T 225 Telecommunication Standardization Bureau (TSB): www.itu.int/ITU-T/ 226 inr/icc/index.html. 228 ICCs can be assigned both to ITU-T and non-ITU-T members and the 229 referenced local ICC website may contain ICCs of operators of both 230 kinds. 232 The ICC is a string of one to six characters, each character being 233 either alphabetic (i.e. A-Z) or numeric (i.e. 0-9) characters. 234 Alphabetic characters in the ICC SHOULD be represented with upper 235 case letters. 237 4. Node and Interface Identifiers 239 An LSR requires identification of the node itself and of its 240 interfaces. We call the identifier associated with a node a Node 241 Identifier (Node_ID). Within the context of a particular node, we 242 call the identifier associated with an interface an Logical Interface 243 Handle or LIH. The combination of Node_ID::LIH we call an Network 244 Interface ID or IF_ID. 246 In existing MPLS deployments Node_IDs are IPv4 addresses. Therefore 247 we have chosen the Node_ID to be a 32-bit value assigned by the 248 operator. Where IPv4 addresses are in use the Node_ID can be 249 automatically mapped to the LSR's /32 IPv4 loopback address. Note 250 that, when IP reachability is not needed, the 32-bit Node_ID is not 251 required to have any association with the IPv4 address space used in 252 the operator's IGP or BGP, other that that they be uniquely chosen 253 within the scope of that operator. 255 GMPLS signaling [2] requires interface identification. We have 256 chosen to adopt the conventions of that RFC. GMPLS allows three 257 formats for the Interface_ID. For IP numbered links, it is simply 258 the IPv4 or IPv6 address associated with the interface. The third 259 format consists of an IPv4 Address plus a 32-bit unsigned integer for 260 the specific interface. 262 For MPLS-TP, we have adopted a format consistent with the third 263 format above. In MPLS-TP, each interface is assigned a 32-bit 264 identifier which we call a Logical Interface Handle (LIH). The LIH 265 MUST be unique within the context of the Node_ID. We map the Node_ID 266 to the field the field which carries the IP address. That is, an 267 IF_ID is a 64-bit identifier consisting of the Node_ID followed by 268 the LIH. The LIH in turn is a 32-bit unsigned integer unique to the 269 node. The LIH value 0 has special meaning (see section 270 Section 7.2.1.3 and must not be used as the LIH in an MPLS-TP IF_ID. 272 In situations where a Node_ID or an IF_ID needs to be globally 273 unique, this is accomplished by prefixing the identifier with the 274 operator's Global_ID. The combination of Global_ID::Node_ID we call 275 an Global Node ID or Global_Node_ID. Likewise, the combination of 276 Global_ID::Node_ID::LIH we call an Global Interface ID or 277 Global_IF_ID. 279 MPLS-TP Tunnels (see section Section 5.1) also need interface 280 identifiers. A procedure for automatically generating these is 281 contained in that section. 283 5. MPLS-TP Tunnel and LSP Identifiers 285 A important construct within MPLS_TP is a connection which is 286 provided across a working and a protection LSP. Within this document 287 we will use the term MPLS-TP Tunnel or simply tunnel for the 288 connection provided by the working and protect LSPs. This section 289 defines an MPLS-TP Tunnel_ID to uniquely identify a tunnel and 290 MPLS-TP LSP_IDs within the context of a tunnel. 292 5.1. MPLS-TP Tunnel Identifiers 294 At each endpoint a tunnel is uniquely identified by the Source 295 Node_ID and a locally assigned tunnel number. Specifically a 296 Tunnel_Num is a 16-bit unsigned integer unique to the node. The 297 concatenation of the two endpoint identifier servers as the full 298 identifier. Thus the format of a Tunnel_ID is: 300 Src-Node_ID::Src-Tunnel_Num::Dst-Node_ID::Dst-Tunnel_Num 302 Where the Tunnel_ID needs to be globally unique, this is accomplished 303 by using globally unique Node_IDs as defined above. Thus a globally 304 unique Tunnel_ID becomes: 306 Src-Global_ID::Src-Node_ID::Src-Tunnel_Num:: Dst-Global_ID::Dst- 307 Node_ID::Dst-Tunnel_Num 309 When an MPLS-TP Tunnel is configured, it MUST be assigned a unique 310 IF_ID at both the source and destination endpoints. As usual, the 311 IF_ID is composed of the local NODE_ID concatenated with a 32-bit 312 LIH. It is RECOMMENDED that the LIH be auto-generated by adding 2^31 313 to the local Tunnel_Num. 315 5.2. MPLS-TP LSP Identifiers 317 Within the scope of an MPLS-TP Tunnel_ID an LSP can be uniquely 318 identified by a single LSP number. Specifically an LSP_Num is a 16- 319 bit unsigned integer unique within the Tunnel_ID. Thus the format of 320 a Tunnel_ID is: 322 Src-Node_ID::Src-Tunnel_Num::Dst-Node_ID::Dst-Tunnel_Num:: LSP_Num 324 Where the LSP_ID needs to be globally unique, this is accomplished by 325 using globally unique Node_IDs as defined above. Thus a globally 326 unique Tunnel_ID becomes: 328 Src-Global_ID::Src-Node_ID::Src-Tunnel_Num:: Dst-Global_ID::Dst- 329 Node_ID::Dst-Tunnel_Num::LSP_Num 331 5.3. Mapping to GMPLS Signalling 333 This section defines the mapping from an MPLS-TP LSP_ID to GMPLS. At 334 this time, GMPLS has yet to be extended to accommodate Global_IDs. 335 Thus a mapping is only made for the network unique form of the 336 LSP_ID. 338 GMPLS signaling [3] uses a 5-tuple to uniquely identify an LSP within 339 a operator's network. This tuple is composed of a Tunnel Endpoint 340 Address, Tunnel_ID, Extended Tunnel ID, and Tunnel Sender Address and 341 (GMPLS) LSP_ID. 343 In situations where a mapping to the GMPLS 5-tuple is required, the 344 following mapping is used. 346 o Tunnel Endpoint Address = Dst-Node_ID 348 o Tunnel_ID = Src-Tunnel_Num 350 o Extended Tunnel_ID = Src-Node_ID 352 o Tunnel Sender Address = Src-Node_ID 354 o LSP_ID = LSP_Num 356 6. Pseudowire Path Identifiers 358 Pseudowire signaling (RFC 4447 [1]) defines two FECs used to signal 359 pseudowires. Of these, FEC Type 129 along with AII Type 2 as defined 360 in RFC 5003 [6] fits the identification requirements of MPLS-TP. 362 In an MPLS-TP environment, a PW is identified by a set of identifiers 363 which can be mapped directly to the elements required by FEC 129 and 364 AII Type 2. To distinguish this identifier from other Pseudowire 365 Identifiers, we call this a Pseudowire Path Identifier or PW_Path_Id. 367 The AII Type 2 is composed of three fields. These are the Global_ID, 368 the Prefix, and the AC_ID. The Global_ID used in this document is 369 identical to the Global_ID defined in RFC 5003. The Node_ID is used 370 as the Prefix. The AC_ID is as defined in RFC 5003. 372 To complete the FEC 129, all that is required is a Attachment Group 373 Identifier (AGI). That field is exactly as specified in RFC 4447. 374 FEC 129 has a notion of Source AII (SAII) and Target AII (TAII). 375 These terms are used relative to the direction of the signaling. In 376 a purely configured environment when referring to the entire PW, this 377 distinction is not critical. That is a FEC 129 of AGIa::AIIb::AIIc 378 is equivalent to AGIa::AIIc::AIIb. We note that in a signaled 379 environment, the required convention in RFC 4447 is that at a 380 particular endpoint, the AII associated with that endpoint comes 381 first. The complete PW_Path_Id is: 383 AGI:Src-Global_ID::Src-Node_ID::Src-AC_ID:: Dst-Global_ID::Dst- 384 Node_ID::Dst-AC_ID. 386 7. Maintenance Identifiers 388 [Note this section needs to reconciled with on going ITU and MPLS WG 389 discussions on Maintenance Points.] 391 In MPLS-TP a Maintenance Entity Group (MEG) represents an Entity that 392 requires management and defines a relationship between a set of 393 maintenance points. A maintenance point is either Maintenance End- 394 point (MEP) or a Maintenance Intermediate Point (MIP). A Maintenance 395 Entity is a relationship between two MEPs. This section defines a 396 means of uniquely identifying Maintenance Entity Groups, Maintenance 397 Entities and uniquely defining MEPs and MIPs within the context of a 398 Maintenance Entity Group. 400 7.1. Maintenance Entity Group Identifiers 402 Maintenance Entity Group Identifiers (MEG_IDs) are required for 403 MPLS-TP Paths and Pseudowires. Two classes of MEG_IDs are defined, 404 one that follows the IP compatible identifier defined above as well 405 as the ICC-format. 407 7.1.1. ICC based MEG_IDs 409 MEG_ID for MPLS-TP LSPs and Pseudowires MAY use the globally unique 410 ICC-based format. 412 In this case, the MEG_ID is a string of up to thirteen characters, 413 each character being either alphabetic (i.e. A-Z) or numeric (i.e. 414 0-9) characters. It consists of two subfields: the ICC (as defined 415 in section 3) followed by a unique MEG code (UMC). 417 The UMC MUST be unique within the organization identified by the ICC. 419 The ICC MEG_ID may be applied equally to MPLS-TP tunnels, a single 420 MPLS-TP LSP, groups of MPLS-TP LSPs, Pseudowires, and groups of 421 Pseudowires. 423 Note that when encoded in a protocol such as in a TLV, a different 424 type needs to be defined for LSP and PWs as the OAM capabilities may 425 be different. 427 7.1.2. IP Compatible MEG_IDs 429 7.1.2.1. MPLS-TP Tunnel MEG_IDs 431 Since a MEG pertains to a single MPLS-TP Tunnel, IP compatible 432 MEG_IDs for MPLS-TP Tunnels are simply the corresponding Tunnel_IDs. 433 We note that while the two identifiers are syntactically identical, 434 they have different semantics. This semantic difference needs to be 435 made clear. For instance if both a MPLS-TP Tunnel_ID and MPLS-TP 436 Tunnel MEG_IDs are to be encoded in TLVs different types need to be 437 assigned for these two identifiers. 439 7.1.2.2. MPLS-TP LSP MEG_IDs 441 MEG_IDs for MPLS-TP LSPs may pertain to one or more LSPs. Therefore 442 the direct mapping used for tunnels is not possible. However an 443 indirect mapping which keeps the formats aligned is possible. This 444 is done by replacing the LSP_Num with a LSP_MEG_Num. Thus the format 445 of a MPLS-TP LSP MEG_ID is: 447 Src-Global_ID::Src-Node_ID::Src-Tunnel_Num:: Dst-Global_ID::Dst- 448 Node_ID::Dst-Tunnel_Num::LSP_MEG_Num 450 When a MEG_ID is assigned to a single MPLS-TP LSP it is RECOMMENDED 451 that the LSP_MEG_Num be assigned equal to the LSP_Num. When a MEG_ID 452 is assigned to a group of MPLS-TP LSPs within a single MPLS-TP 453 Tunnel, it is recommended that the MEG_ID be assigned equal to the 454 LSP_Num of one member of the group of MPLS-TP LSPs. In this 455 situation if the chosen LSP is later deconfigured it is RECOMMENDED 456 that this LSP_Num not be reused unless the new LSP in question will 457 become a member of the same MEG. 459 7.1.2.3. Pseudowire MEG_IDs 461 For Pseudowires a MEG pertains to a single PW. The IP compatible 462 MEG_ID for a PW is simply the corresponding PW_Path_ID. We note that 463 while the two identifiers are syntactically identical, they have 464 different semantics. This semantic difference needs to be made 465 clear. For instance if both a PW_Path_ID and a PW_MEG_ID is to be 466 encoded in TLVs different types need to be assigned for these two 467 identifiers. 469 7.2. Maintenance Points 471 Maintenance points are uniquely associated with a MEG. Within the 472 context of a MEG, MEPs and MIPs must be uniquely identified. This 473 section describes how MIPs and MEPs are identified. 475 Note that depending on the requirements of a particular OAM 476 interaction, the MPLS-TP maintenance entity context may be provided 477 either explicitly using the MEG_IDs described above or implicitly by 478 the label of the received OAM message. 480 7.2.1. Maintenance Point_IDs for MPLS-TP LSPs and Tunnels 482 In order to automatically generate MEP_IDs for MPLS-TP Tunnels and 483 LSPs, we use the elements of identification that are unique to an 484 endpoint. This ensures that MEP_IDs are unique for all Tunnels and 485 LSPs within a operator. When Tunnels or LSPs cross operator 486 boundaries, these are made unique by pre-pending them with the 487 operator's Global_ID. 489 7.2.1.1. MPLS-TP Tunnel_MEP_ID 491 A MPLS-TP Tunnel_MEP_ID is: 493 Src-Node_ID::Src-Tunnel_Num 495 In situations where global uniqueness is required this becomes: 497 Src-Global_ID::Src-Node_ID::Src-Tunnel_Num 499 7.2.1.2. MPLS-TP LSP_MEP_ID 501 A MPLS-TP LSP_MEP_ID is: 503 Src-Node_ID::Src-Tunnel_Num::LSP_Num 505 In situations where global uniqueness is required this becomes: 507 Src-Global_ID::Src-Node_ID::Src-Tunnel_Num::LSP_Num 509 7.2.1.3. MPLS-TP LSP_MIP_ID 511 At a cross connect point, in order to automatically generate MIP_IDs 512 for MPLS-TP LSPs, we simply use the IF_IDs of the two interfaces 513 which are cross connected via the label bindings of the MPLS-TP LSP. 514 If only one MIP is configured, then the MIP_ID is formed using the 515 Node_ID and an LIH of 0. 517 7.2.2. Maintenance Identifiers for Pseudowires 519 Like MPLS-TP LSPs, Pseudowire endpoints (T-PEs) require MEP-IDs. 520 Pseudowire S-PEs, however, are a special case. Here the Maintenance 521 Entity takes on some of the functionality of both a MIP and a MEP. 522 Provisionally we are calling these a Maintenance Point or MP. 524 7.2.2.1. MEP_IDs for PW T-PEs 526 In order to automatically generate MEP_IDs for PWs, we simply use the 527 AGI plus the AII associated with that end of the PW. Thus a MEP_ID 528 for an Pseudowire T-PE takes the form: 530 AGI:Src-Global_ID::Src-Node_ID::Src-AC_ID 532 7.2.2.2. MP_IDs for Pseudowires 534 The MP_ID is formed by a combination of a PW MEP_ID and the 535 identification of the local node. At an S-PE, there are two PW 536 segments. We distinguish the segments by using the MEP-ID which is 537 upstream of the PW segment in question. To complete the 538 identification we suffix this with the identification of the local 539 node. 541 +-------+ +-------+ +-------+ +-------+ 542 | | | | | | | | 543 | A|---------|B C|---------|D E|---------|F | 544 | | | | | | | | 545 +-------+ +-------+ +-------+ +-------+ 546 T-PE1 S-PE2 S-PE3 T-PE4 548 Pseudowire Maintenance Points 550 For example, suppose that in the above figure all of the nodes have 551 Global_ID GID1; the node are represented as named in the figure; and 552 The identification for the Pseudowire is: 554 AGI = AGI1 555 Src-Global_ID = GID1 556 Src-Node_ID = T-PE1 557 Src-AC_ID = AII1 558 Dst-Global_ID = GID1 559 Dst-Node_ID = T-PE1 560 Dst-AC_ID = AII4 562 The MEP_ID at point A would be AGI1::GID1:T-PE1::AII1. The MP_ID at 563 point C would be AGI1::GID1:T-PE1::AII1::GID1:S-PE2. 565 For interaction where the T-PE is acting as the segment endpoint, it 566 too may use the MP_ID. 568 8. Open issues 570 1. We have two means of identifying operators. Should either be 571 allowed in all cases or can we constrain this. I.e. when there 572 are both IP compatible and ITU compatible IDs for an Object can 573 we constrain the operator ID to the corresponding format? 574 Clearly when only one identifier is defined the both must be 575 allowed. 577 2. Details on MEP and MIP identifiers are subject to ongoing 578 discussions. Further based on some discussion in Stockholm, ITU 579 style identifiers for MEPs and MIPs were removed from this 580 version. However, consensus for this needs to be verified. 582 3. Pseudowire Maintenance Points need to be kept aligned with the 583 model for Pseudowire maintenance. 585 4. Identifiers for P2MP entities 587 5. Tandem connection Identification - the identification should be 588 exactly the same as any other MPLS-TP LSP. However, in the ACH 589 TLV draft we could have a different TLV with the same format as 590 an MPLS-TP LSP, if there are places where the distinction becomes 591 important. 593 9. References 595 9.1. Normative References 597 [1] Martini, L., Rosen, E., El-Aawar, N., Smith, T., and G. Heron, 598 "Pseudowire Setup and Maintenance Using the Label Distribution 599 Protocol (LDP)", RFC 4447, April 2006. 601 [2] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) 602 Signaling Functional Description", RFC 3471, January 2003. 604 [3] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) 605 Signaling Resource ReserVation Protocol-Traffic Engineering 606 (RSVP-TE) Extensions", RFC 3473, January 2003. 608 [4] Bradner, S., "Key words for use in RFCs to Indicate Requirement 609 Levels", BCP 14, RFC 2119, March 1997. 611 [5] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., and 612 G. Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", 613 RFC 3209, December 2001. 615 [6] Metz, C., Martini, L., Balus, F., and J. Sugimoto, "Attachment 616 Individual Identifier (AII) Types for Aggregation", RFC 5003, 617 September 2007. 619 [7] Kompella, K., Rekhter, Y., and A. Kullberg, "Signalling 620 Unnumbered Links in CR-LDP (Constraint-Routing Label 621 Distribution Protocol)", RFC 3480, February 2003. 623 [8] Kompella, K., Rekhter, Y., and L. Berger, "Link Bundling in 624 MPLS Traffic Engineering (TE)", RFC 4201, October 2005. 626 [9] Kompella, K. and G. Swallow, "Detecting Multi-Protocol Label 627 Switched (MPLS) Data Plane Failures", RFC 4379, February 2006. 629 [10] Lang, J., Rekhter, Y., and D. Papadimitriou, "RSVP-TE 630 Extensions in Support of End-to-End Generalized Multi-Protocol 631 Label Switching (GMPLS) Recovery", RFC 4872, May 2007. 633 [11] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, "BFD 634 For MPLS LSPs", draft-ietf-bfd-mpls-07 (work in progress), 635 June 2008. 637 [12] Nadeau, T. and C. Pignataro, "Bidirectional Forwarding 638 Detection (BFD) for the Pseudowire Virtual Circuit Connectivity 639 Verification (VCCV)", draft-ietf-pwe3-vccv-bfd-07 (work in 640 progress), July 2009. 642 9.2. Informative References 644 [13] Vigoureux, M., Ward, D., and M. Betts, "Requirements for OAM in 645 MPLS Transport Networks", 646 draft-ietf-mpls-tp-oam-requirements-03 (work in progress), 647 August 2009. 649 [14] Ohta, H., "Assignment of the 'OAM Alert Label' for 650 Multiprotocol Label Switching Architecture (MPLS) Operation and 651 Maintenance (OAM) Functions", RFC 3429, November 2002. 653 [15] Niven-Jenkins, B., Brungard, D., Betts, M., Sprecher, N., and 654 S. Ueno, "MPLS-TP Requirements", 655 draft-ietf-mpls-tp-requirements-10 (work in progress), 656 August 2009. 658 [16] Bocci, M., Bryant, S., Frost, D., and L. Levrau, "A Framework 659 for MPLS in Transport Networks", 660 draft-ietf-mpls-tp-framework-06 (work in progress), 661 October 2009. 663 Authors' Addresses 665 Matthew Bocci 666 Alcatel-Lucent 667 Voyager Place, Shoppenhangers Road 668 Maidenhead, Berks SL6 2PJ 669 UK 671 Email: matthew.bocci@alcatel-lucent.com 673 George Swallow 674 Cisco 676 Email: swallow@cisco.com