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'6') (Obsoleted by RFC 8077) -- Obsolete informational reference (is this intentional?): RFC 4379 (ref. '13') (Obsoleted by RFC 8029) == Outdated reference: A later version (-12) exists of draft-ietf-mpls-tp-framework-10 Summary: 4 errors (**), 0 flaws (~~), 11 warnings (==), 2 comments (--). 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: September 9, 2010 Cisco 6 March 8, 2010 8 MPLS-TP Identifiers 9 draft-ietf-mpls-tp-identifiers-01 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 September 9, 2010. 41 Copyright Notice 43 Copyright (c) 2010 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. MEP_IDs . . . . . . . . . . . . . . . . . . . . . . . . . 11 78 7.2.1. ICC based MEP_IDs . . . . . . . . . . . . . . . . . . 11 79 7.2.2. IP based MEP_IDs . . . . . . . . . . . . . . . . . . . 11 80 7.2.2.1. MEP_IDs for MPLS-TP LSPs and Tunnels . . . . . . . 11 81 7.2.2.2. MEP_IDs for Pseudowires . . . . . . . . . . . . . 12 82 7.2.2.3. MEP_IDs for Pseudowire Segments . . . . . . . . . 12 83 7.3. MIP_IDs . . . . . . . . . . . . . . . . . . . . . . . . . 13 84 8. Open issues . . . . . . . . . . . . . . . . . . . . . . . . . 13 85 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 86 9.1. Normative References . . . . . . . . . . . . . . . . . . . 13 87 9.2. Informative References . . . . . . . . . . . . . . . . . . 14 88 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14 90 1. Introduction 92 This document specifies identifiers to be used in within the 93 Transport Profile of Multiprotocol Label Switching (MPLS-TP). The 94 MPLS-TP requirements [12] require that the elements and objects in an 95 MPLS-TP environment are able to be configured and managed without a 96 control plane. In such an environment many conventions for defining 97 identifiers are possible. This document defines identifiers for 98 MPLS-TP management and OAM functions suitable to ITU conventions and 99 to IP/MPLS conventions. Applicability of the different identifier 100 schemas to different applications are outside the scope of this 101 document. 103 1.1. Terminology 105 AII: Attachment Interface Identifier 107 ASN: Autonomous System Number 109 FEC: Forwarding Equivalence Class 111 GMPLS: Generalized Multi-Protocol Label Switching 113 ICC: ITU Carrier Code 115 LSP: Label Switched Path 117 LSR: Label Switching Router 119 ME: Maintenance Entity 121 MEG: Maintenance Entity Group 123 MEP: Maintenance Entity Group End Point 125 MIP: Maintenance Entity Group Intermediate Point 127 MPLS: Multi-Protocol Label Switching 129 OAM: Operations, Administration and Maintenance 131 P2MP: Point to Multi-Point 133 P2P: Point to Point 135 PSC: Protection State Coordination 137 PW: Pseudowire 138 RSVP: Resource Reservation Protocol 140 RSVP-TE: RSVP Traffic Engineering 142 S-PE: Switching Provider Edge 144 T-PE: Terminating Provider Edge 146 Requirements Language 148 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 149 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 150 document are to be interpreted as described in RFC 2119 [1]. 152 2. Named Entities 154 In order to configure, operate and manage a transport network based 155 on the MPLS Transport Profile, a number of entities require 156 identification. Identifiers for the follow entities are defined in 157 this document: 159 o Operator 161 * ICC 163 * Global_ID 165 o LSR 167 o LSP 169 o PW 171 o Interface 173 o MEG 175 o MEP 177 o MIP 179 o Tunnel 181 Note that we have borrowed the term tunnel from RSVP-TE (RFC 3209) 182 [2] where it is used to describe an entity that provides an LSP 183 connection between a source and destination LSR which in turn is 184 instantiated by one or more LSPs, where the additional LSPs are used 185 for protection or re-grooming of the tunnel. 187 3. Uniquely Identifying an Operator 189 Two forms of identification are defined, one that is compatible with 190 IP operational practice called a Global_ID and one compatible with 191 ITU practice, the ICC. An Operator MAY be identified either by its 192 Global_ID or by its ICC. 194 3.1. The Global ID 196 RFC 5003 [3] defines a globally unique Attachment Interface 197 Identifier (AII). That AII is composed of three parts, a Global ID 198 which uniquely identifies a operator, a prefix, and finally and 199 attachment circuit identifier. We have chosen to use that Global ID 200 for MPLS-TP. Quoting from RFC 5003, section 3.2, "The global ID can 201 contain the 2-octet or 4-octet value of the operator's Autonomous 202 System Number (ASN). It is expected that the global ID will be 203 derived from the globally unique ASN of the autonomous system hosting 204 the PEs containing the actual AIIs. The presence of a global ID 205 based on the operator's ASN ensures that the AII will be globally 206 unique." 208 When the Global_ID is derived from a 2-octet AS number, the two high- 209 order octets of this 4-octet identifier MUST be set to zero. 211 Note that this Global_ID is used solely to provide a globally unique 212 context for other MPLS-TP identifiers. It has nothing to do with the 213 use of the ASN in protocols such as BGP. 215 3.2. ITU Carrier Code 217 M.1400 defines the ITU Carrier Code (ICC) assigned to a network 218 operator/service provider and maintained by the ITU-T 219 Telecommunication Standardization Bureau (TSB): www.itu.int/ITU-T/ 220 inr/icc/index.html. 222 ICCs can be assigned both to ITU-T and non-ITU-T members and the 223 referenced local ICC website may contain ICCs of operators of both 224 kinds. 226 The ICC is a string of one to six characters, each character being 227 either alphabetic (i.e. A-Z) or numeric (i.e. 0-9) characters. 228 Alphabetic characters in the ICC SHOULD be represented with upper 229 case letters. 231 4. Node and Interface Identifiers 233 An LSR requires identification of the node itself and of its 234 interfaces. We call the identifier associated with a node a Node 235 Identifier (Node_ID). Within the context of a particular node, we 236 call the identifier associated with an interface an Logical Interface 237 Handle or LIH. The combination of Node_ID::LIH we call an Network 238 Interface ID or IF_ID. 240 In existing MPLS deployments Node_IDs are IPv4 addresses. Therefore 241 we have chosen the Node_ID to be a 32-bit value assigned by the 242 operator. Where IPv4 addresses are in use the Node_ID can be 243 automatically mapped to the LSR's /32 IPv4 loopback address. Note 244 that, when IP reachability is not needed, the 32-bit Node_ID is not 245 required to have any association with the IPv4 address space used in 246 the operator's IGP or BGP, other that that they be uniquely chosen 247 within the scope of that operator. 249 GMPLS signaling [4] requires interface identification. We have 250 chosen to adopt the conventions of that RFC. GMPLS allows three 251 formats for the Interface_ID. For IP numbered links, it is simply 252 the IPv4 or IPv6 address associated with the interface. The third 253 format consists of an IPv4 Address plus a 32-bit unsigned integer for 254 the specific interface. 256 For MPLS-TP, we have adopted a format consistent with the third 257 format above. In MPLS-TP, each interface is assigned a 32-bit 258 identifier which we call a Logical Interface Handle (LIH). The LIH 259 MUST be unique within the context of the Node_ID. We map the Node_ID 260 to the field the field which carries the IP address. That is, an 261 IF_ID is a 64-bit identifier consisting of the Node_ID followed by 262 the LIH. The LIH in turn is a 32-bit unsigned integer unique to the 263 node. The LIH value 0 has special meaning (see section Section 7.3 264 and must not be used as the LIH in an MPLS-TP IF_ID. 266 In situations where a Node_ID or an IF_ID needs to be globally 267 unique, this is accomplished by prefixing the identifier with the 268 operator's Global_ID. The combination of Global_ID::Node_ID we call 269 an Global Node ID or Global_Node_ID. Likewise, the combination of 270 Global_ID::Node_ID::LIH we call an Global Interface ID or 271 Global_IF_ID. 273 MPLS-TP Tunnels (see section Section 5.1) also need interface 274 identifiers. A procedure for automatically generating these is 275 contained in that section. 277 5. MPLS-TP Tunnel and LSP Identifiers 279 A important construct within MPLS_TP is a connection which is 280 provided across a working and a protection LSP. Within this document 281 we will use the term MPLS-TP Tunnel or simply tunnel for the 282 connection provided by the working and protect LSPs. This section 283 defines an MPLS-TP Tunnel_ID to uniquely identify a tunnel and 284 MPLS-TP LSP_IDs within the context of a tunnel. 286 5.1. MPLS-TP Tunnel Identifiers 288 At each endpoint a tunnel is uniquely identified by the Source 289 Node_ID and a locally assigned tunnel number. Specifically a 290 Tunnel_Num is a 16-bit unsigned integer unique to the node. The 291 concatenation of the two endpoint identifier servers as the full 292 identifier. Thus the format of a Tunnel_ID is: 294 Src-Node_ID::Src-Tunnel_Num::Dst-Node_ID::Dst-Tunnel_Num 296 Where the Tunnel_ID needs to be globally unique, this is accomplished 297 by using globally unique Node_IDs as defined above. Thus a globally 298 unique Tunnel_ID becomes: 300 Src-Global_ID::Src-Node_ID::Src-Tunnel_Num:: Dst-Global_ID::Dst- 301 Node_ID::Dst-Tunnel_Num 303 When an MPLS-TP Tunnel is configured, it MUST be assigned a unique 304 IF_ID at both the source and destination endpoints. As usual, the 305 IF_ID is composed of the local NODE_ID concatenated with a 32-bit 306 LIH. It is RECOMMENDED that the LIH be auto-generated by adding 2^31 307 to the local Tunnel_Num. 309 5.2. MPLS-TP LSP Identifiers 311 Within the scope of an MPLS-TP Tunnel_ID an LSP can be uniquely 312 identified by a single LSP number. Specifically an LSP_Num is a 16- 313 bit unsigned integer unique within the Tunnel_ID. Thus the format of 314 a Tunnel_ID is: 316 Src-Node_ID::Src-Tunnel_Num::Dst-Node_ID::Dst-Tunnel_Num:: LSP_Num 318 Where the LSP_ID needs to be globally unique, this is accomplished by 319 using globally unique Node_IDs as defined above. Thus a globally 320 unique Tunnel_ID becomes: 322 Src-Global_ID::Src-Node_ID::Src-Tunnel_Num:: Dst-Global_ID::Dst- 323 Node_ID::Dst-Tunnel_Num::LSP_Num 325 5.3. Mapping to GMPLS Signalling 327 This section defines the mapping from an MPLS-TP LSP_ID to GMPLS. At 328 this time, GMPLS has yet to be extended to accommodate Global_IDs. 329 Thus a mapping is only made for the network unique form of the 330 LSP_ID. 332 GMPLS signaling [5] uses a 5-tuple to uniquely identify an LSP within 333 a operator's network. This tuple is composed of a Tunnel Endpoint 334 Address, Tunnel_ID, Extended Tunnel ID, and Tunnel Sender Address and 335 (GMPLS) LSP_ID. 337 In situations where a mapping to the GMPLS 5-tuple is required, the 338 following mapping is used. 340 o Tunnel Endpoint Address = Dst-Node_ID 342 o Tunnel_ID = Src-Tunnel_Num 344 o Extended Tunnel_ID = Src-Node_ID 346 o Tunnel Sender Address = Src-Node_ID 348 o LSP_ID = LSP_Num 350 6. Pseudowire Path Identifiers 352 Pseudowire signaling (RFC 4447 [6]) defines two FECs used to signal 353 pseudowires. Of these, FEC Type 129 along with AII Type 2 as defined 354 in RFC 5003 [3] fits the identification requirements of MPLS-TP. 356 In an MPLS-TP environment, a PW is identified by a set of identifiers 357 which can be mapped directly to the elements required by FEC 129 and 358 AII Type 2. To distinguish this identifier from other Pseudowire 359 Identifiers, we call this a Pseudowire Path Identifier or PW_Path_Id. 361 The AII Type 2 is composed of three fields. These are the Global_ID, 362 the Prefix, and the AC_ID. The Global_ID used in this document is 363 identical to the Global_ID defined in RFC 5003. The Node_ID is used 364 as the Prefix. The AC_ID is as defined in RFC 5003. 366 To complete the FEC 129, all that is required is a Attachment Group 367 Identifier (AGI). That field is exactly as specified in RFC 4447. 368 FEC 129 has a notion of Source AII (SAII) and Target AII (TAII). 369 These terms are used relative to the direction of the signaling. In 370 a purely configured environment when referring to the entire PW, this 371 distinction is not critical. That is a FEC 129 of AGIa::AIIb::AIIc 372 is equivalent to AGIa::AIIc::AIIb. We note that in a signaled 373 environment, the required convention in RFC 4447 is that at a 374 particular endpoint, the AII associated with that endpoint comes 375 first. The complete PW_Path_Id is: 377 AGI:Src-Global_ID::Src-Node_ID::Src-AC_ID:: Dst-Global_ID::Dst- 378 Node_ID::Dst-AC_ID. 380 7. Maintenance Identifiers 382 [Note this section needs to reconciled with the MPLS-TP OAM 383 Framework] 385 In MPLS-TP a Maintenance Entity Group (MEG) represents an Entity that 386 requires management and defines a relationship between a set of 387 maintenance points. A maintenance point is either Maintenance Entity 388 Group End-point (MEP) or a Maintenance Entity Group Intermediate 389 Point (MIP). Maintenance points are uniquely associated with a MEG. 390 Within the context of a MEG, MEPs and MIPs must be uniquely 391 identified. This section defines a means of uniquely identifying 392 Maintenance Entity Groups, Maintenance Entities and uniquely defining 393 MEPs and MIPs within the context of a Maintenance Entity Group. 395 Note that depending on the requirements of a particular OAM 396 interaction, the MPLS-TP maintenance entity context may be provided 397 either explicitly using the MEG_IDs described above or implicitly by 398 the label of the received OAM message. 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. MEP_IDs 471 7.2.1. ICC based MEP_IDs 473 ICC-based MEP_IDs for MPLS-TP LSPs and Pseudowires MAY be formed by 474 appending a unique number to the MEG_ID defined in section 475 Section 7.1.1 above. Within the context of a particular MEG, we call 476 the identifier associated with a MEP the MEP Index (MEP_Index). The 477 MEP_Index is administratively assigned and is encoded as a 16-bit 478 unsigned integer. An ICC-based MEP_ID is: 480 MEG_ID::MEP_Index 482 An ICC-based MEP ID is globally unique by construction given the ICC- 483 based MEG_ID global uniqueness. 485 7.2.2. IP based MEP_IDs 487 7.2.2.1. MEP_IDs for MPLS-TP LSPs and Tunnels 489 In order to automatically generate MEP_IDs for MPLS-TP Tunnels and 490 LSPs, we use the elements of identification that are unique to an 491 endpoint. This ensures that MEP_IDs are unique for all Tunnels and 492 LSPs within a operator. When Tunnels or LSPs cross operator 493 boundaries, these are made unique by pre-pending them with the 494 operator's Global_ID. 496 7.2.2.1.1. MPLS-TP Tunnel_MEP_ID 498 A MPLS-TP Tunnel_MEP_ID is: 500 Src-Node_ID::Src-Tunnel_Num 502 In situations where global uniqueness is required this becomes: 504 Src-Global_ID::Src-Node_ID::Src-Tunnel_Num 506 7.2.2.1.2. MPLS-TP LSP_MEP_ID 508 A MPLS-TP LSP_MEP_ID is: 510 Src-Node_ID::Src-Tunnel_Num::LSP_Num 512 In situations where global uniqueness is required this becomes: 514 Src-Global_ID::Src-Node_ID::Src-Tunnel_Num::LSP_Num 516 7.2.2.2. MEP_IDs for Pseudowires 518 Like MPLS-TP LSPs, Pseudowire endpoints (T-PEs) require MEP_IDs. In 519 order to automatically generate MEP_IDs for PWs, we simply use the 520 AGI plus the AII associated with that end of the PW. Thus a MEP_ID 521 used in end-to-end for an Pseudowire T-PE takes the form: 523 AGI:Src-Global_ID::Src-Node_ID::Src-AC_ID 525 7.2.2.3. MEP_IDs for Pseudowire Segments 527 In some OAM communications, messages are originated at one end of a 528 PW segment and relayed to the other end by setting the TTL of the PW 529 label to one. 531 The MEP_ID Is Formed by a combination of a PW MEP_ID and the 532 identification of the local node. At an S-PE, there are two PW 533 segments. We distinguish the segments by using the MEP_ID which is 534 upstream of the PW segment in question. To complete the 535 identification we suffix this with the identification of the local 536 node. 538 +-------+ +-------+ +-------+ +-------+ 539 | | | | | | | | 540 | A|---------|B C|---------|D E|---------|F | 541 | | | | | | | | 542 +-------+ +-------+ +-------+ +-------+ 543 T-PE1 S-PE2 S-PE3 T-PE4 545 Pseudowire Maintenance Points 547 For example, suppose that in the above figure all of the nodes have 548 Global_ID GID1; the node are represented as named in the figure; and 549 The identification for the Pseudowire is: 551 AGI = AGI1 552 Src-Global_ID = GID1 553 Src-Node_ID = T-PE1 554 Src-AC_ID = AII1 555 Dst-Global_ID = GID1 556 Dst-Node_ID = T-PE1 557 Dst-AC_ID = AII4 559 The MEP_ID at point A would be AGI1::GID1:T-PE1::AII1. The MP_ID at 560 point C would be AGI1::GID1:T-PE1::AII1::GID1:S-PE2. 562 For interaction where the T-PE is acting as the segment endpoint, it 563 too may use the Pseudowire Segment MEP_ID. 565 7.3. MIP_IDs 567 At a cross connect point, in order to automatically generate MIP_IDs 568 for MPLS-TP, we simply use the IF_IDs of the two interfaces which are 569 cross connected via the label bindings of the MPLS-TP LSP. If only 570 one MIP is configured, then the MIP_ID is formed using the Node_ID 571 and an LIH of 0. In some contexts, such as LSP Ping[13], the Node_ID 572 alone may be used as the MEP_ID. 574 8. Open issues 576 1. MEPs and MIPs need to be aligned with MPLS-TP OAM Framework. 578 2. Identifiers for P2MP entities. 580 9. References 582 9.1. Normative References 584 [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement 585 Levels", BCP 14, RFC 2119, March 1997. 587 [2] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., and 588 G. Swallow, "RSVP-TE: Extensions to RSVP for LSP Tunnels", 589 RFC 3209, December 2001. 591 [3] Metz, C., Martini, L., Balus, F., and J. Sugimoto, "Attachment 592 Individual Identifier (AII) Types for Aggregation", RFC 5003, 593 September 2007. 595 [4] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) 596 Signaling Functional Description", RFC 3471, January 2003. 598 [5] Berger, L., "Generalized Multi-Protocol Label Switching (GMPLS) 599 Signaling Resource ReserVation Protocol-Traffic Engineering 600 (RSVP-TE) Extensions", RFC 3473, January 2003. 602 [6] Martini, L., Rosen, E., El-Aawar, N., Smith, T., and G. Heron, 603 "Pseudowire Setup and Maintenance Using the Label Distribution 604 Protocol (LDP)", RFC 4447, April 2006. 606 [7] Kompella, K., Rekhter, Y., and A. Kullberg, "Signalling 607 Unnumbered Links in CR-LDP (Constraint-Routing Label 608 Distribution Protocol)", RFC 3480, February 2003. 610 [8] Kompella, K., Rekhter, Y., and L. Berger, "Link Bundling in 611 MPLS Traffic Engineering (TE)", RFC 4201, October 2005. 613 [9] Lang, J., Rekhter, Y., and D. Papadimitriou, "RSVP-TE 614 Extensions in Support of End-to-End Generalized Multi-Protocol 615 Label Switching (GMPLS) Recovery", RFC 4872, May 2007. 617 [10] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, "BFD 618 For MPLS LSPs", draft-ietf-bfd-mpls-07 (work in progress), 619 June 2008. 621 [11] Nadeau, T. and C. Pignataro, "Bidirectional Forwarding 622 Detection (BFD) for the Pseudowire Virtual Circuit Connectivity 623 Verification (VCCV)", draft-ietf-pwe3-vccv-bfd-07 (work in 624 progress), July 2009. 626 9.2. Informative References 628 [12] Vigoureux, M. and D. Ward, "Requirements for OAM in MPLS 629 Transport Networks", draft-ietf-mpls-tp-oam-requirements-06 630 (work in progress), March 2010. 632 [13] Kompella, K. and G. Swallow, "Detecting Multi-Protocol Label 633 Switched (MPLS) Data Plane Failures", RFC 4379, February 2006. 635 [14] Ohta, H., "Assignment of the 'OAM Alert Label' for 636 Multiprotocol Label Switching Architecture (MPLS) Operation and 637 Maintenance (OAM) Functions", RFC 3429, November 2002. 639 [15] Niven-Jenkins, B., Brungard, D., Betts, M., Sprecher, N., and 640 S. Ueno, "MPLS-TP Requirements", 641 draft-ietf-mpls-tp-requirements-10 (work in progress), 642 August 2009. 644 [16] Bocci, M., Bryant, S., Frost, D., Levrau, L., and L. Berger, "A 645 Framework for MPLS in Transport Networks", 646 draft-ietf-mpls-tp-framework-10 (work in progress), 647 February 2010. 649 Authors' Addresses 651 Matthew Bocci 652 Alcatel-Lucent 653 Voyager Place, Shoppenhangers Road 654 Maidenhead, Berks SL6 2PJ 655 UK 657 Email: matthew.bocci@alcatel-lucent.com 659 George Swallow 660 Cisco 662 Email: swallow@cisco.com