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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 TEAS WG A. Deshmukh 3 Internet-Draft K. Kompella 4 Intended status: Standards Track Juniper Networks, Inc. 5 Expires: May 4, 2017 October 31, 2016 7 RSVP Extensions for RMR 8 draft-deshmukh-rsvp-rmr-extension-01 10 Abstract 12 Rings are the most common topology in access and aggregation 13 networks. However, the use of MPLS as the transport protocol for 14 rings is very limited today. draft-ietf-mpls-rmr-02 describes a 15 mechanism to handle rings efficiently using MPLS. This document 16 describes the extensions to the RSVP protocol for signaling MPLS 17 label switched paths in rings. 19 Requirements Language 21 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 22 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 23 document are to be interpreted as described in [RFC2119]. 25 Status of This Memo 27 This Internet-Draft is submitted in full conformance with the 28 provisions of BCP 78 and BCP 79. 30 Internet-Drafts are working documents of the Internet Engineering 31 Task Force (IETF). Note that other groups may also distribute 32 working documents as Internet-Drafts. The list of current Internet- 33 Drafts is at http://datatracker.ietf.org/drafts/current/. 35 Internet-Drafts are draft documents valid for a maximum of six months 36 and may be updated, replaced, or obsoleted by other documents at any 37 time. It is inappropriate to use Internet-Drafts as reference 38 material or to cite them other than as "work in progress." 40 This Internet-Draft will expire on May 4, 2017. 42 Copyright Notice 44 Copyright (c) 2016 IETF Trust and the persons identified as the 45 document authors. All rights reserved. 47 This document is subject to BCP 78 and the IETF Trust's Legal 48 Provisions Relating to IETF Documents 49 (http://trustee.ietf.org/license-info) in effect on the date of 50 publication of this document. Please review these documents 51 carefully, as they describe your rights and restrictions with respect 52 to this document. Code Components extracted from this document must 53 include Simplified BSD License text as described in Section 4.e of 54 the Trust Legal Provisions and are provided without warranty as 55 described in the Simplified BSD License. 57 Table of Contents 59 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 60 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 61 3. RSVP Extensions . . . . . . . . . . . . . . . . . . . . . . . 4 62 3.1. Session Object . . . . . . . . . . . . . . . . . . . . . 4 63 3.2. SENDER_TEMPLATE,FILTER_SPEC Objects . . . . . . . . . . . 5 64 4. Ring Signaling Procedures . . . . . . . . . . . . . . . . . . 5 65 4.1. Differences from regular RSVP-TE LSPs . . . . . . . . . . 5 66 4.2. LSP signaling . . . . . . . . . . . . . . . . . . . . . . 5 67 4.2.1. Path Propagation for RMR . . . . . . . . . . . . . . 7 68 4.2.2. Resv Processing for RMR . . . . . . . . . . . . . . . 8 69 4.3. Protection . . . . . . . . . . . . . . . . . . . . . . . 9 70 4.4. Ring changes . . . . . . . . . . . . . . . . . . . . . . 10 71 4.5. Bandwidth management . . . . . . . . . . . . . . . . . . 11 72 5. Security Considerations . . . . . . . . . . . . . . . . . . . 13 73 6. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 13 74 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 75 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 76 8.1. Normative References . . . . . . . . . . . . . . . . . . 13 77 8.2. Informative References . . . . . . . . . . . . . . . . . 14 78 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 80 1. Introduction 82 This document extends RSVP-TE [RFC3209] to establish label-switched 83 path (LSP) tunnels in the ring topology. Rings are auto-discovered 84 using the mechanisms mentioned in the [draft-ietf-mpls-rmr-02]. 85 Either IS-IS [RFC5305] or OSPF[RFC3630] can be used as the IGP for 86 auto-discovering the rings. 88 After the rings are auto-discovered, each ring node knows its 89 clockwise (CW) and anti-clockwise (AC) ring neighbors and its ring 90 links. All of the express links in the ring also get identified as 91 part of the auto-discovery process. At this point, every node in the 92 ring informs the RSVP protocol to begin the signaling of the ring 93 LSPs. 95 Section 2 covers the terminology used in this document. Section 3 96 presents the RSVP protocol extensions needed to support MPLS rings. 97 Section 4 describes the procedures of RSVP LSP signaling in detail. 99 2. Terminology 101 A ring consists of a subset of n nodes {R_i, 0 <= i < n}. We define 102 the direction from node R_i to R_i+1 as "clockwise" (CW) and the 103 reverse direction as "anti-clockwise" (AC). As there may be several 104 rings in a graph, we number each ring with a distinct ring ID RID. 106 R0 . . . R1 107 . . 108 R7 R2 109 Anti- | . Ring . | 110 Clockwise | . . | Clockwise 111 v . RID = 17 . v 112 R6 R3 113 . . 114 R5 . . . R4 116 Figure 1: Ring with 8 nodes 118 The following terminology is used for ring LSPs: 120 Ring ID (RID): A non-zero number that identifies a ring; this is 121 unique in some scope of a Service Provider's network. A node may 122 belong to multiple rings. 124 Ring node: A member of a ring. Note that a device may belong to 125 several rings. 127 Node index: A logical numbering of nodes in a ring, from zero upto 128 one less than the ring size. Used purely for exposition in this 129 document. 131 Ring neighbors: Nodes whose indices differ by one (modulo ring 132 size). 134 Ring links: Links that connect ring neighbors. 136 Express links: Links that connect non-neighboring ring nodes. 138 MP2P LSP: Each LSP in the ring is a multipoint to point LSP such 139 that LSP can have multiple ingress nodes and one egress node. 141 3. RSVP Extensions 143 Due to the new ring LSP semantics, the signaling-message 144 identification of ring LSPs will be different than the regular RSVP 145 LSPs. So, a new C-Type is defined here for the SESSION object. This 146 new C-Type will help to clearly differentiate ring LSPs from regular 147 LSPs. In addition, new flags are introduced in the SESSION object to 148 represent the ring direction of the corresponding Path message. 150 3.1. Session Object 152 Class = SESSION, LSP_TUNNEL_IPv4 C-Type = TBD 154 0 1 2 3 155 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 1 156 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 157 | Ring anchor node address | 158 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 159 | Ring Flags | MBB ID | 160 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 161 | Ring ID | 162 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 164 SESSION Object 166 Ring anchor node address: IPv4 address of the anchor node. Each 167 anchor node creates a LSP addressed to itself. 169 MBB ID: A 16-bit identifier used in the SESSION. This "Make- 170 before-break" (MBB) ID is useful for graceful ring changes. If a 171 new node is being added to the ring or some existing node goes 172 down and we have to signal a smaller ring, in those cases, anchor 173 node creates a new tunnel with a different "MBB ID". 175 Ring ID: A 32-bit number that identifies a ring; this is unique in 176 some scope of a Service Provider's network. This number remains 177 constant throughout the existence of ring. 179 Ring Flags: For each ring, the anchor node starts signaling of a 180 ring LSP. Ring LSP RL_i, anchored on node R_i, consists of two 181 counter-rotating unicast LSPs that start and end at R_i. One LSP 182 will be in the clockwise direction and other LSP will be in the 183 anti-clockwise direction. A ring LSP is "multipoint": any node 184 R_j can use RL_i to send traffic to R_i; this can be in either the 185 CW or AC directions, or both (i.e., load balanced). Two new flags 186 are defined in the SESSION object which define the ring direction 187 of the corresponding Path message. 189 ClockWise(CW) Direction 0x01: This flag indicates that the 190 corresponding Path message is traveling in the ClockWise(CW) 191 direction along the ring. 193 Anti-ClockWise(AC) Direction 0x02: This flag indicates that the 194 corresponding Path message is traveling in the Anti-ClockWise(AC) 195 direction along the ring. 197 3.2. SENDER_TEMPLATE,FILTER_SPEC Objects 199 There will be no changes to the SENDER_TEMPLATE and FILTER_SPEC 200 objects. The format of the above 2 objects will be similar to the 201 definitions in RFC 3209. [RFC3209] Only the semantics of these 202 objects will slightly change. This will be explained in section 203 Section 4.5 below. 205 4. Ring Signaling Procedures 207 A ring node indicates in its IGP updates the ring LSP signaling 208 protocols that it supports. This can be LDP and/or RSVP-TE. 209 Ideally, each node should support both. If the ring is configured 210 with RSVP as the signaling protocol, then once a ring node R_i knows 211 the RID, its ring links and directions, it kicks off ring RSVP LSP 212 signaling automatically. 214 4.1. Differences from regular RSVP-TE LSPs 216 Ring LSPs differ from regular RSVP-TE LSPs in several ways: 218 1. Ring LSPs (by construction) form a loop. 220 2. Ring LSPs are multipoint-to-point. Any ring node can inject 221 traffic into a ring LSP. 223 3. The bandwidth of a ring LSP can change hop-to-hop. 225 4. Ring LSPs are protected without the use of bypass or detour LSPs. 226 Ring LSP protection is akin to SONET/SDH ring protection. 228 4.2. LSP signaling 230 After the ring auto-discovery process, each anchor node creates a LSP 231 addressed to itself. This ring LSP contains of a pair of counter- 232 rotating unicast LSPs. So, for a ring containing N nodes, there will 233 be 2N total LSPs signaled. 235 There is no need for ERO object in the Path message. The Path 236 message for ring LSPs has the following format: 238 ::= [ ] 239 240 241 242 [ ] 243 245 ::= | 246 247 ::= 249 The anchor node creates 2 Path messages traveling in opposite 250 directions. The SESSION format MUST be as per the description in 251 Section 3.1. The anchor node which creates the LSP will insert it's 252 own address in the "Ring node anchor address" field of the SESSION 253 object. So effectively, the Path messages are addressed to the 254 originating node itself. 256 The SESSION flags of these 2 Path messages are different. The Path 257 message sent to the CW neighbor MUST have the CW flag set in the 258 SESSION object to signal the LSP going in the clockwise direction. 259 The Path message sent to the AC neighbor MUST have the AC flag set to 260 signal the LSP in the anti-clockwise direction. The details for 261 signaling over express links will be given in a future version. 263 When an incoming Path message is received at the ring node R_i, it 264 consults the results of auto-discovery to find the appropriate ring 265 neighbor. If the incoming Path message has CW direction flag set, 266 then R_i sends a Path message to its CW ring neighbor (and vice 267 versa) after including its own SENDER_DESCRIPTOR in the path message. 268 Thus, there is no need of ERO in the Path message. The Path message 269 is routed locally at each ring based on the ring auto-discovery 270 calculations. 272 The RESV message for ring LSPs also uses the new RING_IPv4 SESSION 273 object. When the Path message originated from the anchor node R_i 274 reaches back to R_i, R_i generates a Resv message. Note that this 275 means that anchor node is both Ingress and Egress for the Path 276 message. The Resv message copies the same ring flags as received in 277 the corresponding Path message. So, a Resv message for a CW LSP goes 278 in the AC direction (unlike the Path message, which goes CW). This 279 is done to correctly match Path and corresponding Resv messages at 280 transit ring nodes. Upon receiving Resv message with CW flag set, 281 the ring node will forward the Resv message to its AC neighbor. 283 Each ring node R_i allocates CW and AC labels for each ring LSP RL_k. 284 As the signaling propagates around the ring, CW and AC labels are 285 exchanged. When R_i receives CW and AC labels for RL_k from its ring 286 neighbors, primary and fast reroute (FRR) paths for RL_k are 287 installed at R_i. 289 Consider the following three nodes of the ring, and their signaling 290 interactions for LSP RL_5 originating from anchor node R5: 292 P5_CW -> P5_CW -> 293 Q5_CW <- Q5_CW <- 294 ... ------ R7 --------- R8 --------- R9 ------ ... 295 P5_AC <- P5_AC <- 296 Q5_AC -> Q5_AC -> 298 P corresponds to the Path message and Q corresponds to the Resv 299 message. 301 As explained above, an RMR LSP consists of two counter-rotating ring 302 LSPs that start and end at the same node, say R1. As such, this 303 appears to cause a loop, something that is normally avoided by RSVP- 304 TE. There are some benefits to this: 306 Having a ring LSP form a loop allows the anchor node R1 to ping 307 itself and thus verify the end-to-end operation of the LSP. This, in 308 conjunction with link-level OAM, offers a good indication of the 309 operational state of the LSP. Also, having R1 to be the ingress 310 means that R1 can initiate the Path messages for the two ring LSPs. 311 This avoids R1 having to coordinate with its neighbors to signal the 312 LSPs, and simplifies the case where a ring update changes R1's ring 313 neighbors. The cost of this is a little more signaling and a couple 314 more label entries in the LFIB. However, we will let implementation 315 guide us to the wisdom of this approach. 317 4.2.1. Path Propagation for RMR 319 Ring LSPs are MP2P in nature. It means that every non-egress node is 320 also an ingress and a merge-point for the LSP. Focussing on ring- 321 LSP-0 (i.e ring-LSPs starting at R0): 323 R0---->R1---->R2---->R3---->R4---->R5---->R6--->R7--->R0(CW LSP) 324 R0---->R7---->R6---->R5---->R4---->R3---->R2--->R1--->R0(ACW LSP) 326 Each ring node inserts a new SENDER_TEMPLATE object into an incoming 327 Path message. The procedure for that is as follows: 329 When a ring node R3 receives a Path message initiated by anchor node 330 R0(for anchor lsp "lsp0"), R3 SHOULD make a copy of the received Path 331 message for "lsp0". R3 then inserts a new sender-template object 332 into the Path message for "lsp0". In the sender-template object, R3 333 uses the sender address as the loopback address of node R3 and lsp-id 334 = X. R3 then forwards this modified Path message to it's ring 335 neighbor. 337 So at this point, when Path messages heads out at R3, there will be 4 338 different SENDER_TEMPLATE objects in the outgoing Path message for 339 lsp0: 341 ----------------------------------------------------- 342 |SENDER_TEMPLATE_0 : SENDER_ADDRESS = R0, LSP_ID = 1 | 343 ----------------------------------------------------- 344 |SENDER_TEMPLATE_1 : SENDER_ADDRESS = R1, LSP_ID = 1 | 345 ----------------------------------------------------- 346 |SENDER_TEMPLATE_2 : SENDER_ADDRESS = R2, LSP_ID = 1 | 347 ----------------------------------------------------- 348 |SENDER_TEMPLATE_3 : SENDER_ADDRESS = R3, LSP_ID = 1 | 349 ----------------------------------------------------- 351 4.2.2. Resv Processing for RMR 353 When Egress node R0 receives the modified Path message, it replies 354 with the a Resv message containing multiple FLOW_DESCRIPTOR objects. 355 There should be 1 FLOW_DESCRIPTOR object corresponding to each of the 356 SENDER_TEMPLATE object in the incoming Path message. The SESSION 357 object of the Resv message will exactly match with the received Path 358 message. 360 [RFC 3209] already supports receiving a Resv message with multiple 361 flow-descriptors in it, as described in section 3.2 in that document. 362 In each flow-descriptor there is a separate: 364 a. FLOW_SPEC object corresponding to the SENDER_TSPEC that was sent 365 in the Path message which could be admitted after admission-control 366 downstream, and 368 b. FILTER_SPEC object corresponding to SENDER_TEMPLATE that was sent 369 in the Path message that could be admitted after admission-control 370 downstream. 372 Each transit node removes the FLOW-DESCRIPTOR corresponding to itself 373 from the Resv message before sending the Resv message upstream. 375 4.3. Protection 377 In the rings, there are no protection LSPs -- no node or link bypass 378 LSPs, no standby LSPs and no detours. Protection is via the "other" 379 direction around the ring, which is why ring LSPs are in counter- 380 rotating pairs. Protection works in the same way for link, node and 381 ring LSP failures. 383 Since each ring LSP is a MP2P LSP, any ring node can inject traffic 384 onto a LSP whose anchor might be a different ring node. To achieve 385 the above, an ingress route will be installed as follows at every 386 ring node J, for a given ring-LSP with anchor Rk (say 1.2.3.4). 388 1.2.3.4 -> (Push CL_J+1,K, NH: R_J+1) # CW 389 -> (Push AL_J-1,K, NH: R_J-1) # AC 391 CL = Clockwise label 392 AL = Anti-Clockwise label 394 Traffic will either be load balanced in the CW and AC directions or 395 the traffic will be sent on just CW or AC lsp based on parameters 396 such as hop-count, policy etc. 398 Also, 2 transit routes will be installed for the anchor LSP 399 transiting from node Rj as follows: 401 CL_J,K -> SWAP(CL_J+1,K, NH: R_J+1) #CW 402 -> SWAP(AL_J-1,K , NH: R_J-1) #AC 404 CL = Clockwise label 405 AL = Anti-Clockwise label 406 CW NH has weight 1, AC NH has higher-weight. 408 AL_J,K -> SWAP(AL_J-1,K , NH: R_J-1) #AC 409 -> SWAP(CL_J+1,K, NH: R_J+1) #CW 411 CL = Clockwise label 412 AL = Anti-Clockwise label 413 AC NH has weight 1, CW NH has higher weight. 415 Suppose a packet headed in anti-clockwise direction towards R5 and it 416 arrives at node R8. Lets say that now R8 learns there is a link 417 failure in the AC direction. R8 reroutes this packet back onto the 418 clockwise direction. This reroute action is pre-programmed in the 419 LFIB, to minimize the time between detection of a fault and the 420 corresponding recovery action. 422 At this time, R8 also sends a notification to R7 that the AC 423 direction is not working, so that R7 can similarly switch traffic to 424 the CW direction. These notification SHOULD propagate CW until each 425 traffic source on the ring CW of the failure uses the CW 426 direction.For RSVP-TE, this notification is sent in the form of 427 PathErr message. 429 To provide this notification, the ring node detecting failure SHOULD 430 send a Path Error message with error code of "Notify" and an error 431 value field of ("Tunnel locally repaired"). This Path Error code and 432 value is same as defined in RFC 4090[RFC4090] for the notification of 433 local repair. 435 Note that the failure of a node or a link will not necessarily affect 436 all ring LSPs. Thus, it is important to identify the affected LSPs 437 and only switch the affected LSPs. 439 4.4. Ring changes 441 A ring node can go down resulting in a smaller ring or a new node can 442 be added to the ring which will increase the ring size. In both of 443 the above cases, the ring auto-discovery process SHOULD kick in and 444 it SHOULD calculate a new ring with the changed ring nodes. 446 When the ring auto-discovery process is complete, IGP will signal 447 RSVP to begin the MBB process for the existing ring LSPs. For this 448 MBB process, the anchor node will create a new Path message with a 449 different "MBB ID" in the SESSION object. All other fields in the 450 SESSION Object will remain same as the existing Path message(before 451 the ring change). 453 This new Path message will then propagate along the ring neighbors in 454 the same way as the original Path message. Each ring neighbor SHOULD 455 forward the Path message to it's appropriate neighbor based on the 456 new auto-discovery calculations. 458 For the ring links which are common between the old and new LSPs, the 459 LSPs will share resources(SE style reservation) on those ring links. 460 Note that here we are using MBB_ID in the SESSION object to share 461 resources instead of the LSP_ID in the SENDER_TEMPLATE Object(which 462 is used in RSVP-TE for sharing resources as described in RFC 3209 463 [RFC4090]). The LSP_ID use is reserved for a different functionality 464 as described in section Section 4.5. 466 4.5. Bandwidth management 468 For RSVP-TE LSPs, bandwidths may be signaled in both directions. 469 However, these are not provisioned either; rather, one does "reverse 470 call admission control". When a service needs to use an LSP, the 471 ring node where the traffic enters the ring attempts to increase the 472 bandwidth on the LSP to the egress. If successful, the service is 473 admitted to the ring. 475 . R0 . . . R1 476 . __________|| . 477 . / ________| . 478 R7 / / R2 479 Anti- | . / / . | 480 Clockwise | . | / . | Clockwise 481 v . | \ . v 482 R6 \ R3 483 . \ . 484 R5 . . . R4 486 Figure 2: BW Management in Ring with 8 nodes 488 Let's say that Ring node R5 wants to increase the BW for the LSP 489 whose egress is at node R1. To achieve this BW increase, Ring node 490 R5 has to increase BW along the LSP anchored at node R1(say lsp1). 492 R5 makes a copy of the existing ring Path message for lsp1. R5 then 493 modifies the sender-template object from the copied Path message for 494 "lsp1". In the sender-template object, R5 uses the sender address as 495 the loopback address of node R5 and lsp-id = X+1. R5 also modifies 496 the TSPEC object which represents the BW increase/decrease in this 497 new Path message. R5 then forwards this new Path message to it's 498 ring neighbor. The original anchor Path message has sender address 499 as loopback address of R1. 501 Now, let's say, node 5 wants to increase BW again for lsp1, then R5 502 adds a new SENDER_TEMPLATE object in the existing Path message for 503 "lsp1" with sender address as loopback of node 5 and lsp-id = X+2. 504 So at this point, there will be 2 different SENDER_TEMPLATE objects 505 corresponding to node 5 in the outgoing path message. 507 ----------------------------------------------------- 508 |SENDER_TEMPLATE_0 : SENDER_ADDRESS = R0, LSP_ID = 1 | 509 ----------------------------------------------------- 510 |SENDER_TEMPLATE_1 : SENDER_ADDRESS = R1, LSP_ID = 1 | 511 ----------------------------------------------------- 512 | ........ | 513 ----------------------------------------------------- 514 |SENDER_TEMPLATE_5 : SENDER_ADDRESS = R5, LSP_ID = 1 | 515 ----------------------------------------------------- 516 |SENDER_TEMPLATE_5 : SENDER_ADDRESS = R5, LSP_ID = 2 | 517 ----------------------------------------------------- 519 Similarly, if node R6 wants to increase the BW for "lsp1", it SHOULD 520 create a new Path message containing SENDER_TEMPLATE object with 521 sender address = loopback of node 6 and lsp-id = Y+1. Thus, it 522 should be noted that each ring-node independently tracks its own lsp- 523 ID that is currently in-use on a given RMR sub-LSP. This lsp-ID 524 value will (could) be different for each ring-node for a given ring 525 sub-LSP. 527 If sufficient BW is available all the way towards ring node R1, then 528 this new Path message reaches node R1. R1 generates a Resv message 529 with the correct FILTER_SPEC object corresponding to the received 530 SENDER_TEMPLATE object. This Resv message will also have the correct 531 FLOWSPEC object as per the requested bandwidth. 533 If sufficient BW is not available at some downstream (say node R9), 534 then ring node R9 SHOULD generate a PathErr message with the 535 corresponding Sender Template Object. When node R5 receives this 536 PathErr message, R5 understands that the BW increase was not 537 successful. Note that the existing established bandwidths for lsp1 538 are not affected by this new PathErr message. 540 When ring node R5 no longer needs the BW reservation, then ring node 541 R5 SHOULD originate a PathTear message with the appropriate Sender 542 Template Object as described above. Every downstream node SHOULD 543 then remove bandwidth allocated on the corresponding link on receipt 544 of this PathTear message. 546 Also, note that as part of this BW increase or decrease process, any 547 ring node does not actually change any label associated with the LSP. 548 So, the label remains same as it was signaled initially when the 549 anchor LSP came up. 551 5. Security Considerations 553 It is not anticipated that either the notion of MPLS rings or the 554 extensions to various protocols to support them will cause new 555 security loopholes. As this document is updated, this section will 556 also be updated. 558 6. Contributors 560 Ravi Singh 561 Juniper Networks, Inc. 562 1133 Innovation Way 563 Sunnyvale, CA 94089 564 USA 566 Email: ravis@juniper.net 568 Santosh Esale 569 Juniper Networks, Inc. 570 1133 Innovation Way 571 Sunnyvale, CA 94089 572 USA 574 Email: sesale@juniper.net 576 Raveendra Torvi 577 Juniper Networks, Inc. 578 10 Technology Park Dr 579 Westford, MA 01886 580 USA 582 Email: rtorvi@juniper.net 584 7. IANA Considerations 586 Requests to IANA will be made in a future version of this document. 588 8. References 590 8.1. Normative References 592 [I-D.ietf-mpls-rmr] 593 Kompella, K. and L. Contreras, "Resilient MPLS Rings", 594 draft-ietf-mpls-rmr-03 (work in progress), October 2016. 596 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 597 Requirement Levels", BCP 14, RFC 2119, 598 DOI 10.17487/RFC2119, March 1997, 599 . 601 8.2. Informative References 603 [I-D.dai-mpls-rsvp-te-mbb-label-reuse] 604 Dai, M. and M. Chaudhry, "MPLS RSVP-TE MBB Label Reuse", 605 draft-dai-mpls-rsvp-te-mbb-label-reuse-01 (work in 606 progress), September 2015. 608 [RFC2205] Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S. 609 Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1 610 Functional Specification", RFC 2205, DOI 10.17487/RFC2205, 611 September 1997, . 613 [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V., 614 and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP 615 Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001, 616 . 618 [RFC3630] Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering 619 (TE) Extensions to OSPF Version 2", RFC 3630, 620 DOI 10.17487/RFC3630, September 2003, 621 . 623 [RFC4090] Pan, P., Ed., Swallow, G., Ed., and A. Atlas, Ed., "Fast 624 Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090, 625 DOI 10.17487/RFC4090, May 2005, 626 . 628 [RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic 629 Engineering", RFC 5305, DOI 10.17487/RFC5305, October 630 2008, . 632 Authors' Addresses 634 Abhishek Deshmukh 635 Juniper Networks, Inc. 636 10 Technology Park Dr 637 Westford, MA 01886 638 USA 640 Email: adeshmukh@juniper.net 641 Kireeti Kompella 642 Juniper Networks, Inc. 643 1133 Innovation Way 644 Sunnyvale, CA 94089 645 USA 647 Email: kireeti@juniper.net