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'P2MP FRR' Summary: 0 errors (**), 0 flaws (~~), 21 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Internet Engineering Task Force H. Chen 3 Internet-Draft Huawei Technologies 4 Intended status: Standards Track N. So 5 Expires: September 18, 2014 Tata Communications 6 A. Liu 7 Ericsson 8 F. Xu 9 Verizon 10 M. Toy 11 Comcast 12 L. Huang 13 China Mobile 14 L. Liu 15 UC Davis 16 March 17, 2014 18 Extensions to RSVP-TE for LSP Egress Local Protection 19 draft-ietf-mpls-rsvp-egress-protection-00.txt 21 Abstract 23 This document describes extensions to Resource Reservation Protocol - 24 Traffic Engineering (RSVP-TE) for locally protecting egress nodes of 25 a Traffic Engineered (TE) Label Switched Path (LSP) in a Multi- 26 Protocol Label Switching (MPLS) and Generalized MPLS (GMPLS) network. 28 Status of this Memo 30 This Internet-Draft is submitted to IETF in full conformance with the 31 provisions of BCP 78 and BCP 79. 33 Internet-Drafts are working documents of the Internet Engineering 34 Task Force (IETF). Note that other groups may also distribute 35 working documents as Internet-Drafts. The list of current Internet- 36 Drafts is at http://datatracker.ietf.org/drafts/current/. 38 Internet-Drafts are draft documents valid for a maximum of six months 39 and may be updated, replaced, or obsoleted by other documents at any 40 time. It is inappropriate to use Internet-Drafts as reference 41 material or to cite them other than as "work in progress." 43 This Internet-Draft will expire on September 18, 2014. 45 Copyright Notice 47 Copyright (c) 2014 IETF Trust and the persons identified as the 48 document authors. All rights reserved. 50 This document is subject to BCP 78 and the IETF Trust's Legal 51 Provisions Relating to IETF Documents 52 (http://trustee.ietf.org/license-info) in effect on the date of 53 publication of this document. Please review these documents 54 carefully, as they describe your rights and restrictions with respect 55 to this document. Code Components extracted from this document must 56 include Simplified BSD License text as described in Section 4.e of 57 the Trust Legal Provisions and are provided without warranty as 58 described in the Simplified BSD License. 60 Table of Contents 62 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 63 1.1. An Example of Egress Local Protection . . . . . . . . . . 3 64 1.2. Egress Local Protection with FRR . . . . . . . . . . . . . 4 65 2. Conventions Used in This Document . . . . . . . . . . . . . . 4 66 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 67 4. Protocol Extensions . . . . . . . . . . . . . . . . . . . . . 4 68 4.1. EGRESS_BACKUP Object . . . . . . . . . . . . . . . . . . . 4 69 4.2. Flags in FAST_REROUTE . . . . . . . . . . . . . . . . . . 6 70 4.3. Path Message . . . . . . . . . . . . . . . . . . . . . . . 6 71 5. Egress Protection Behaviors . . . . . . . . . . . . . . . . . 6 72 5.1. Ingress Behavior . . . . . . . . . . . . . . . . . . . . . 6 73 5.2. Intermediate Node and PLR Behavior . . . . . . . . . . . . 7 74 5.2.1. Signaling for One-to-One Protection . . . . . . . . . 8 75 5.2.2. Signaling for Facility Protection . . . . . . . . . . 8 76 5.2.3. Signaling for S2L Sub LSP Protection . . . . . . . . . 9 77 5.2.4. PLR Procedures during Local Repair . . . . . . . . . . 10 78 6. Considering Application Traffic . . . . . . . . . . . . . . . 10 79 6.1. A Typical Application . . . . . . . . . . . . . . . . . . 10 80 6.2. PLR Procedure for Applications . . . . . . . . . . . . . . 11 81 6.3. Egress Procedures for Applications . . . . . . . . . . . . 11 82 7. Security Considerations . . . . . . . . . . . . . . . . . . . 12 83 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 84 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 12 85 10. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 13 86 11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 87 11.1. Normative References . . . . . . . . . . . . . . . . . . . 13 88 11.2. Informative References . . . . . . . . . . . . . . . . . . 14 89 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14 91 1. Introduction 93 RFC 4090 describes two methods for protecting the transit nodes of a 94 P2P LSP: one-to-one and facility protection. RFC 4875 specifies how 95 to use them to protect the transit nodes of a P2MP LSP. However, 96 they do not mention any local protection for an egress of an LSP. 98 To protect the egresses of an LSP (P2P or P2MP), an existing approach 99 sets up a backup LSP from a backup ingress (or the ingress of the 100 LSP) to the backup egresses, where each egress is paired with a 101 backup egress and protected by the backup egress. 103 This approach may use more resources and provide slow fault recovery. 104 This document specifies extensions to RSVP-TE for local protection of 105 an egress of an LSP, which overcomes these disadvantages. 107 1.1. An Example of Egress Local Protection 109 Figure 1 shows an example of using backup LSPs to locally protect 110 egresses of a primary P2MP LSP from ingress R1 to two egresses: L1 111 and L2. The primary LSP is represented by star(*) lines and backup 112 LSPs by hyphen(-) lines. 114 La and Lb are the designated backup egresses for egresses L1 and L2 115 respectively. To distinguish an egress (e.g., L1) from a backup 116 egress (e.g., La), an egress is called a primary egress if needed. 118 The backup LSP for protecting L1 is from its upstream node R3 to 119 backup egress La. The one for protecting L2 is from R5 to Lb. 121 [R2]*****[R3]*****[L1] 122 * \ :.....: $ **** Primary LSP 123 * \ $ ---- Backup LSP 124 * \ [CE1] .... BFD Session 125 * \ $ $ Link 126 * \ $ $ 127 * [La] $ 128 * 129 [R1]******[R4]*******[R5]*****[L2] 130 $ \ :.....: $ 131 $ \ $ 132 [S] \ [CE2] 133 \ $ 134 \ $ 135 [Lb] 137 Figure 1: Backup LSP for Locally Protecting Egress 139 During normal operations, the traffic carried by the P2MP LSP is sent 140 through R3 to L1, which delivers the traffic to its destination CE1. 141 When R3 detects the failure of L1, R3 switches the traffic to the 142 backup LSP to backup egress La, which delivers the traffic to CE1. 143 The time for switching the traffic is within tens of milliseconds. 145 The failure of a primary egress (e.g., L1 in the figure) MAY be 146 detected by its upstream node (e.g., R3 in the figure) through a BFD 147 between the upstream node and the egress in MPLS networks. Exactly 148 how the failure is detected is out of scope for this document. 150 1.2. Egress Local Protection with FRR 152 Using the egress local protection and the FRR, we can locally protect 153 the egresses, the links and the intermediate nodes of an LSP. The 154 traffic switchover time is within tens of milliseconds whenever an 155 egress, any of the links and the intermediate nodes of the LSP fails. 157 The egress nodes of the LSP can be locally protected via the egress 158 local protection. All the links and the intermediate nodes of the 159 LSP can be locally protected through using the FRR. 161 2. Conventions Used in This Document 163 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 164 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 165 document are to be interpreted as described in RFC 2119. 167 3. Terminology 169 This document uses terminologies defined in RFC 2205, RFC 3031, RFC 170 3209, RFC 3473, RFC 4090, RFC 4461, and RFC 4875. 172 4. Protocol Extensions 174 A new object EGRESS_BACKUP is defined for egress local protection. 175 It contains a backup egress for a primary egress. 177 4.1. EGRESS_BACKUP Object 179 The class of the EGRESS_BACKUP object is TBD-1 to be assigned by 180 IANA. The C-Type of the EGRESS_BACKUP IPv4/IPv6 object is TBD-2/ 181 TBD-3 to be assigned by IANA. 183 EGRESS_BACKUP Class Num = TBD-1, IPv4/IPv6 C-Type = TBD-2/TBD-3 185 0 1 2 3 186 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 1 187 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 188 ~ Egress Backup destination IPv4/IPv6 address ~ 189 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 190 ~ Egress Primary destination IPv4/IPv6 address ~ 191 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 192 ~ (Subobjects) ~ 193 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 195 o Egress Backup destination IPv4/IPv6 address: 196 IPv4/IPv6 address of the backup egress node 197 o Egress Primary destination IPv4/IPv6 address: 198 IPv4/IPv6 address of the primary egress node 200 The Subobjects are optional. One of them is P2P LSP ID IPv4/IPv6 201 subobject, whose body has the following format and Type is TBD-4/ 202 TBD-5. It may be used to identify a backup LSP. 204 0 1 2 3 205 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 1 206 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 207 ~ P2P LSP Tunnel Egress IPv4/IPv6 Address (4/16 bytes) ~ 208 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 209 | Reserved | Tunnel ID | 210 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 211 ~ Extended Tunnel ID (4/16 bytes) ~ 212 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 214 o P2P LSP Tunnel Egress IPv4/IPv6 Address: 215 IPv4/IPv6 address of the egress of the tunnel 216 o Tunnel ID: 217 A 16-bit identifier that is constant over the life of the tunnel 218 o Extended Tunnel ID: 219 A 4/16-byte identifier being constant over the life of the tunnel 221 Another one is Label subobject, whose body has the format below and 222 Type is TBD-6 to be assigned by IANA. 224 0 1 2 3 225 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 1 226 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 227 | Label | 228 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 230 4.2. Flags in FAST_REROUTE 232 A bit of the flags in the FAST_REROUTE object may be used to indicate 233 whether S2L Sub LSP is desired for protecting an egress of a P2MP LSP 234 or One-to-One Backup is preferred for protecting an egress of a P2P 235 LSP when the "Facility Backup Desired" flag is set. This bit is 236 called "S2L Sub LSP Backup Desired" or "One-to-One Backup Preferred". 238 4.3. Path Message 240 A Path message is enhanced to carry the information about a backup 241 egress for a primary egress of an LSP through including an egress 242 backup descriptor list. The format of the enhanced Path message is 243 illustrated below. 245 ::= [ ] 246 [ [ | ] ...] 247 [ ] 248 [ ] 249 [ ] [ ...] 250 [ ] [ ] 251 [ ] [ ... ] 252 [] 253 [] 255 The egress backup descriptor list in the message is defined below. 256 It is a sequence of EGRESS_BACKUP objects, each of which describes a 257 pair of a primary egress and a backup egress. 259 ::= 260 261 [ ] 263 ::= 265 5. Egress Protection Behaviors 267 5.1. Ingress Behavior 269 To protect a primary egress of an LSP, the ingress MUST set the 270 "label recording desired" flag and the "node protection desired" flag 271 in the SESSION_ATTRIBUTE object. 273 If one-to-one backup or facility backup method is desired to protect 274 a primary egress of an LSP, the ingress SHOULD include a FAST_REROUTE 275 object and set the "One-to-One Backup Desired" or "Facility Backup 276 Desired" flag. 278 If S2L Sub LSP backup method is desired to protect a primary egress 279 of a P2MP LSP, the ingress SHOULD include a FAST_REROUTE object and 280 set the "S2L Sub LSP Backup Desired" flag. 282 Note that if "Facility Backup Desired" flag is set for protecting the 283 intermediate nodes of a primary P2P LSP, but we want to use "One-to- 284 One Backup" for protecting the egress of the LSP, then the ingress 285 SHOULD set "One-to-One Backup Preferred" flag. 287 Optionally, a backup egress may be configured on the ingress of an 288 LSP to protect a primary egress of the LSP. 290 The ingress sends a Path message for the LSP with the objects above 291 and an optional egress backup descriptor list. For each primary 292 egress of the LSP to be protected, the ingress adds an EGRESS_BACKUP 293 object into the list if the backup egress is given. The object 294 contains the primary egress and the backup egress for protecting the 295 primary egress. 297 5.2. Intermediate Node and PLR Behavior 299 If an intermediate node of an LSP receives the Path message with an 300 egress backup descriptor list and it is not an upstream node of any 301 primary egress of the LSP, it forwards the list unchanged. 303 If the intermediate node is the upstream node of a primary egress to 304 be protected, it determines the backup egress, obtains a path for the 305 backup LSP and sets up the backup LSP along the path. 307 The PLR (upstream node of the primary egress) tries to get the backup 308 egress from EGRESS_BACKUP in the egress backup descriptor list if the 309 Path message contains the list. If the PLR can not get it, the PLR 310 tries to find the backup egress, which is not the primary egress but 311 has the same IP address as the destination IP address of the LSP. 313 Note that the primary egress and the backup egress SHOULD have a same 314 local address configured, and the cost to the local address on the 315 backup egress SHOULD be much bigger than the cost to the local 316 address on the primary egress. Thus another name such as virtual 317 node based egress protection may be used for egress local protection. 319 After obtaining the backup egress, the PLR tries to compute a path 320 from itself to the backup egress. 322 The PLR then sets up the backup LSP along the path obtained. It 323 provides one-to-one backup protection for the primary egress if the 324 "One-to-One Backup Desired" or "One-to-One Backup Preferred" flag is 325 set in the message; otherwise, it provides facility backup protection 326 if the "Facility Backup Desired flag" is set. 328 The PLR sets the protection flags in the RRO Sub-object for the 329 primary egress in the Resv message according to the status of the 330 primary egress and the backup LSP protecting the primary egress. For 331 example, it will set the "local protection available" and the "node 332 protection" flag indicating that the primary egress is protected when 333 the backup LSP is up and ready for protecting the primary egress. 335 5.2.1. Signaling for One-to-One Protection 337 The behavior of the upstream node of a primary egress of an LSP as a 338 PLR is the same as that of a PLR for one-to-one backup method 339 described in RFC 4090 except for that the upstream node creates a 340 backup LSP from itself to a backup egress. 342 If the LSP is a P2MP LSP and a primary egress of the LSP is a transit 343 node (i.e., bud node), the upstream node of the primary egress as a 344 PLR also creates a backup LSP from itself to each of the next hops of 345 the primary egress. 347 When the PLR detects the failure of the primary egress, it MUST 348 switch the packets from the primary LSP to the backup LSP to the 349 backup egress. For the failure of the bud node of a P2MP LSP, the 350 PLR MUST also switch the packets to the backup LSPs to the bud node's 351 next hops, where the packets are merged into the primary LSP. 353 5.2.2. Signaling for Facility Protection 355 Except for backup LSP and downstream label, the behavior of the 356 upstream node of the primary egress of a primary LSP as a PLR follows 357 the PLR behavior for facility backup method described in RFC 4090. 359 For a number of primary P2P LSPs going through the same PLR to the 360 same primary egress, the primary egress of these LSPs may be 361 protected by one backup LSP from the PLR to the backup egress 362 designated for protecting the primary egress. 364 The PLR selects or creates a backup LSP from itself to the backup 365 egress. If there is a backup LSP that satisfies the constraints 366 given in the Path message, then this one is selected; otherwise, a 367 new backup LSP to the backup egress will be created. 369 After getting the backup LSP, the PLR associates the backup LSP with 370 a primary LSP for protecting its primary egress. The PLR records 371 that the backup LSP is used to protect the primary LSP against its 372 primary egress failure and includes an EGRESS_BACKUP object in the 373 Path message to the primary egress. The object contains the backup 374 egress and the backup LSP ID. It indicates that the primary egress 375 SHOULD send the backup egress the primary LSP label as UA label. 377 After receiving the Path message with the EGRESS_BACKUP, the primary 378 egress includes the information about the primary LSP label in the 379 Resv message with an EGRESS_BACKUP object as UA label. When the PLR 380 receives the Resv message with the information about the UA label, it 381 includes the information in the Path message for the backup LSP to 382 the backup egress. Thus the primary LSP label as UA label is sent to 383 the backup egress from the primary egress. 385 When the PLR detects the failure of the primary egress, it redirects 386 the packets from the primary LSP into the backup LSP to backup egress 387 using the primary LSP label from the primary egress as an inner 388 label. The backup egress delivers the packets to the same 389 destinations as the primary egress using the backup LSP label as 390 context label and the inner label as UA label. 392 5.2.3. Signaling for S2L Sub LSP Protection 394 The S2L Sub LSP Protection is used to protect a primary egress of a 395 P2MP LSP. Its major advantage is that the application traffic 396 carried by the LSP is easily protected against the egress failure. 398 The PLR determines to protect a primary egress of a P2MP LSP via S2L 399 sub LSP protection when it receives a Path message with flag "S2L Sub 400 LSP Backup Desired" set. 402 The PLR sets up the backup S2L sub LSP to the backup egress, creates 403 and maintains its state in the same way as of setting up a source to 404 leaf (S2L) sub LSP defined in RFC 4875 from the signaling's point of 405 view. It computes a path for the backup LSP from itself to the 406 backup egress, constructs and sends a Path message along the path, 407 receives and processes a Resv message responding to the Path message. 409 After receiving the Resv message for the backup LSP, the PLR creates 410 a forwarding entry with an inactive state or flag called inactive 411 forwarding entry. This inactive forwarding entry is not used to 412 forward any data traffic during normal operations. 414 When the PLR detects the failure of the primary egress, it changes 415 the forwarding entry for the backup LSP to active. Thus, the PLR 416 forwards the traffic to the backup egress through the backup LSP, 417 which sends the traffic to its destination. 419 5.2.4. PLR Procedures during Local Repair 421 When the upstream node of a primary egress of an LSP as a PLR detects 422 the failure of the primary egress, it follows the procedures defined 423 in section 6.5 of RFC 4090. It SHOULD notify the ingress about the 424 failure of the primary egress in the same way as a PLR notifies the 425 ingress about the failure of an intermediate node. 427 In the local revertive mode, the PLR re-signals each of the primary 428 LSPs that were routed over the restored resource once it detects that 429 the resource is restored. Every primary LSP successfully re-signaled 430 along the restored resource is switched back. 432 Moreover, the PLR lets the upstream part of the primary LSP stay 433 after the primary egress fails. The downstream part of the primary 434 LSP from the PLR to the primary egress SHOULD be removed. 436 6. Considering Application Traffic 438 This section focuses on the application traffic carried by P2P LSPs. 439 When a primary egress of a P2MP LSP fails, the application traffic 440 carried by the P2MP LSP may be delivered to the same destination by 441 the backup egress since the inner label if any for the traffic is a 442 upstream assigned label for every egress of the P2MP LSP. 444 6.1. A Typical Application 446 L3VPN is a typical application. An existing solution (refer to 447 Figure 2) for protecting L3VPN traffic against egress failure 448 includes: 1) A multi-hop BFD session between ingress R1 and egress L1 449 of primary LSP; 2) A backup LSP from ingress R1 to backup egress La; 450 3) La sends R1 VPN backup label and related information via BGP; 4) 451 R1 has a VRF with two sets of routes: one uses primary LSP and L1 as 452 next hop; the other uses backup LSP and La as next hop. 454 CE1,CE2 in [R2]*****[R3]*****[L1] **** Primary LSP 455 one VPN * : $ ---- Backup LSP 456 * .................: $ .... BFD Session 457 [R1] ..: [CE2] $ Link 458 $ \ $ $ 459 $ \ $ 460 [CE1] [R4]-----[R5]-----[La](BGP sends R1 VPN backup label) 462 Figure 2: Protect Egress for L3VPN Traffic 464 In normal operations, R1 sends the traffic from CE1 through primary 465 LSP with VPN label received from L1 as inner label to L1, which 466 delivers the traffic to CE2 using VPN label. 468 When R1 detects the failure of L1, R1 sends the traffic from CE1 via 469 backup LSP with VPN backup label received from La as inner label to 470 La, which delivers the traffic to CE2 using VPN backup label. 472 A new solution (refer to Figure 3) with egress local protection for 473 protecting L3VPN traffic includes: 1) A BFD session between R3 and 474 egress L1 of primary LSP; 2) A backup LSP from R3 to backup egress 475 La; 3) L1 sends La VPN label as UA label and related information; 4) 476 L1 and La is virtualized as one. This can be achieved by configuring 477 a same local address on L1 and La, using the address as a destination 478 of the LSP and BGP next hop for VPN traffic. 480 CE1,CE2 in [R2]*****[R3]*****[L1] **** Primary LSP 481 one VPN * \ :.....: $ ---- Backup LSP 482 * \ $ .... BFD Session 483 [R1] \ [CE2] $ Link 484 $ \ $ $ 485 $ \ $ 486 [CE1] [La](VPN label from L1 as UA label) 488 Figure 3: Locally Protect Egress for L3VPN Traffic 490 When R3 detects L1's failure, R3 sends the traffic from primary LSP 491 via backup LSP to La, which delivers the traffic to CE2 using VPN 492 label as UA label under the backup LSP label as a context label. 494 6.2. PLR Procedure for Applications 496 When the PLR gets a backup LSP from itself to a backup egress for 497 protecting a primary egress of a primary LSP, it includes an 498 EGRESS_BACKUP object in the Path message for the primary LSP. The 499 object contains the ID information of the backup LSP and indicates 500 that the primary egress SHOULD send the backup egress the application 501 traffic label (e.g., VPN label) as UA label when needed. 503 6.3. Egress Procedures for Applications 505 When a primary egress of an LSP sends the ingress of the LSP a label 506 for an application such as a VPN, it SHOULD send the backup egress 507 for protecting the primary egress the label as a UA label via BGP or 508 another protocol. Exactly how the label is sent is out of scope for 509 this document. 511 When the backup egress receives a UA label from the primary egress, 512 it adds a forwarding entry with the label into the LFIB for the 513 primary egress. When the backup egress receives a packet from the 514 backup LSP, it uses the top label as a context label to find the LFIB 515 for the primary egress and the inner label to deliver the packet to 516 the same destination as the primary egress according to the LFIB. 518 7. Security Considerations 520 In principle this document does not introduce new security issues. 521 The security considerations pertaining to RFC 4090, RFC 4875 and 522 other RSVP protocols remain relevant. 524 8. IANA Considerations 526 IANA considerations for new objects will be specified after the 527 objects used are decided upon. 529 9. Contributors 531 Boris Zhang 532 Telus Communications 533 200 Consilium Pl Floor 15 534 Toronto, ON M1H 3J3 535 Canada 536 Email: Boris.Zhang@telus.com 538 Zhenbin Li 539 Huawei Technologies 540 Huawei Bld., No.156 Beiqing Rd. 541 Beijing 100095 542 China 543 Email: lizhenbin@huawei.com 545 Nan Meng 546 Huawei Technologies 547 Huawei Bld., No.156 Beiqing Rd. 548 Beijing 100095 549 China 550 Email: mengnan@huawei.com 552 Vic Liu 553 China Mobile 554 No.32 Xuanwumen West Street, Xicheng District 555 Beijing, 100053 556 China 557 Email: liuzhiheng@chinamobile.com 559 10. Acknowledgement 561 The authors would like to thank Richard Li, Tarek Saad, Lizhong Jin, 562 Ravi Torvi, Eric Gray, Olufemi Komolafe, Michael Yue, Rob Rennison, 563 Neil Harrison, Kannan Sampath, Yimin Shen, Ronhazli Adam and Quintin 564 Zhao for their valuable comments and suggestions on this draft. 566 11. References 568 11.1. Normative References 570 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 571 Requirement Levels", BCP 14, RFC 2119, March 1997. 573 [RFC3692] Narten, T., "Assigning Experimental and Testing Numbers 574 Considered Useful", BCP 82, RFC 3692, January 2004. 576 [RFC2205] Braden, B., Zhang, L., Berson, S., Herzog, S., and S. 577 Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1 578 Functional Specification", RFC 2205, September 1997. 580 [RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol 581 Label Switching Architecture", RFC 3031, January 2001. 583 [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., 584 and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP 585 Tunnels", RFC 3209, December 2001. 587 [RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching 588 (GMPLS) Signaling Resource ReserVation Protocol-Traffic 589 Engineering (RSVP-TE) Extensions", RFC 3473, January 2003. 591 [RFC4090] Pan, P., Swallow, G., and A. Atlas, "Fast Reroute 592 Extensions to RSVP-TE for LSP Tunnels", RFC 4090, 593 May 2005. 595 [RFC4875] Aggarwal, R., Papadimitriou, D., and S. Yasukawa, 596 "Extensions to Resource Reservation Protocol - Traffic 597 Engineering (RSVP-TE) for Point-to-Multipoint TE Label 598 Switched Paths (LSPs)", RFC 4875, May 2007. 600 [RFC5331] Aggarwal, R., Rekhter, Y., and E. Rosen, "MPLS Upstream 601 Label Assignment and Context-Specific Label Space", 602 RFC 5331, August 2008. 604 [RFC5786] Aggarwal, R. and K. Kompella, "Advertising a Router's 605 Local Addresses in OSPF Traffic Engineering (TE) 606 Extensions", RFC 5786, March 2010. 608 [P2MP FRR] 609 Le Roux, J., Aggarwal, R., Vasseur, J., and M. Vigoureux, 610 "P2MP MPLS-TE Fast Reroute with P2MP Bypass Tunnels", 611 draft-leroux-mpls-p2mp-te-bypass , March 1997. 613 11.2. Informative References 615 [RFC4461] Yasukawa, S., "Signaling Requirements for Point-to- 616 Multipoint Traffic-Engineered MPLS Label Switched Paths 617 (LSPs)", RFC 4461, April 2006. 619 Authors' Addresses 621 Huaimo Chen 622 Huawei Technologies 623 Boston, MA 624 USA 626 Email: huaimo.chen@huawei.com 628 Ning So 629 Tata Communications 630 2613 Fairbourne Cir. 631 Plano, TX 75082 632 USA 634 Email: ning.so@tatacommunications.com 636 Autumn Liu 637 Ericsson 638 CA 639 USA 641 Email: autumn.liu@ericsson.com 642 Fengman Xu 643 Verizon 644 2400 N. Glenville Dr 645 Richardson, TX 75082 646 USA 648 Email: fengman.xu@verizon.com 650 Mehmet Toy 651 Comcast 652 1800 Bishops Gate Blvd. 653 Mount Laurel, NJ 08054 654 USA 656 Email: mehmet_toy@cable.comcast.com 658 Lu Huang 659 China Mobile 660 No.32 Xuanwumen West Street, Xicheng District 661 Beijing, 100053 662 China 664 Email: huanglu@chinamobile.com 666 Lei Liu 667 UC Davis 668 USA 670 Email: liulei.kddi@gmail.com