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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 PCE Working Group H. Ananthakrishnan 3 Internet-Draft Packet Design 4 Intended status: Standards Track S. Sivabalan 5 Expires: December 31, 2017 Cisco 6 C. Barth 7 R. Torvi 8 Juniper Networks 9 I. Minei 10 Google, Inc 11 E. Crabbe 12 Individual Contributor 13 D. Dhody 14 Huawei Technologies 15 June 29, 2017 17 PCEP Extensions for MPSL-TE LSP Path Protection with stateful PCE 18 draft-ananthakrishnan-pce-stateful-path-protection-03 20 Abstract 22 A stateful Path Computation Element (PCE) is capable of computing as 23 well as controlling via Path Computation Element Protocol (PCEP) 24 Multiprotocol Label Switching Traffic Engineering Label Switched 25 Paths (MPLS LSP). Furthermore, it is also possible for a stateful 26 PCE to create, maintain, and delete LSPs. This document describes 27 PCEP extension to associate two or more LSPs to provide end-to-end 28 path protection. 30 Status of This Memo 32 This Internet-Draft is submitted in full conformance with the 33 provisions of BCP 78 and BCP 79. 35 Internet-Drafts are working documents of the Internet Engineering 36 Task Force (IETF). Note that other groups may also distribute 37 working documents as Internet-Drafts. The list of current Internet- 38 Drafts is at http://datatracker.ietf.org/drafts/current/. 40 Internet-Drafts are draft documents valid for a maximum of six months 41 and may be updated, replaced, or obsoleted by other documents at any 42 time. It is inappropriate to use Internet-Drafts as reference 43 material or to cite them other than as "work in progress." 45 This Internet-Draft will expire on December 31, 2017. 47 Copyright Notice 49 Copyright (c) 2017 IETF Trust and the persons identified as the 50 document authors. All rights reserved. 52 This document is subject to BCP 78 and the IETF Trust's Legal 53 Provisions Relating to IETF Documents 54 (http://trustee.ietf.org/license-info) in effect on the date of 55 publication of this document. Please review these documents 56 carefully, as they describe your rights and restrictions with respect 57 to this document. Code Components extracted from this document must 58 include Simplified BSD License text as described in Section 4.e of 59 the Trust Legal Provisions and are provided without warranty as 60 described in the Simplified BSD License. 62 Table of Contents 64 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 65 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 4 66 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 67 3. PCEP Extensions . . . . . . . . . . . . . . . . . . . . . . . 4 68 3.1. Path Protection Association Type . . . . . . . . . . . . 4 69 3.2. Path Protection Association TLV . . . . . . . . . . . . . 5 70 4. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 6 71 4.1. PCC Initiated LSPs . . . . . . . . . . . . . . . . . . . 6 72 4.2. PCE Initiated LSPs . . . . . . . . . . . . . . . . . . . 7 73 4.3. State Synchronization . . . . . . . . . . . . . . . . . . 7 74 4.4. Error Handling . . . . . . . . . . . . . . . . . . . . . 7 75 5. Other considerations . . . . . . . . . . . . . . . . . . . . 7 76 6. IANA considerations . . . . . . . . . . . . . . . . . . . . . 7 77 6.1. Association Type . . . . . . . . . . . . . . . . . . . . 8 78 6.2. PPAG TLV . . . . . . . . . . . . . . . . . . . . . . . . 8 79 6.3. PCEP Errors . . . . . . . . . . . . . . . . . . . . . . . 9 80 7. Security Considerations . . . . . . . . . . . . . . . . . . . 9 81 8. Manageability Considerations . . . . . . . . . . . . . . . . 10 82 8.1. Control of Function and Policy . . . . . . . . . . . . . 10 83 8.2. Information and Data Models . . . . . . . . . . . . . . . 10 84 8.3. Liveness Detection and Monitoring . . . . . . . . . . . . 10 85 8.4. Verify Correct Operations . . . . . . . . . . . . . . . . 10 86 8.5. Requirements On Other Protocols . . . . . . . . . . . . . 10 87 8.6. Impact On Network Operations . . . . . . . . . . . . . . 10 88 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10 89 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 90 10.1. Normative References . . . . . . . . . . . . . . . . . . 11 91 10.2. Information References . . . . . . . . . . . . . . . . . 11 92 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12 94 1. Introduction 96 [RFC5440] describes PCEP for communication between a Path Computation 97 Client (PCC) and a PCE or between one a pair of PCEs as per 98 [RFC4655]. A PCE computes paths for MPLS-TE LSPs based on various 99 constraints and optimization criteria. 101 Stateful pce [I-D.ietf-pce-stateful-pce] specifies a set of 102 extensions to PCEP to enable stateful control of paths such as MPLS 103 TE LSPs between and across PCEP sessions in compliance with 104 [RFC4657]. It includes mechanisms to effect LSP state 105 synchronization between PCCs and PCEs, delegation of control of LSPs 106 to PCEs, and PCE control of timing and sequence of path computations 107 within and across PCEP sessions and focuses on a model where LSPs are 108 configured on the PCC and control over them is delegated to the PCE. 109 Furthermore, a mechanism to dynamically instantiate LSPs on a PCC 110 based on the requests from a stateful PCE or a controller using 111 stateful PCE is specified in [I-D.ietf-pce-pce-initiated-lsp]. 113 Path protection refers to a paradigm in which the working LSP is 114 protected by one or more protection LSP(s). When the working LSP 115 fails, protection LSP(s) is/are activated. When the working LSPs are 116 computed and controlled by the PCE, there is benefit in a mode of 117 operation where protection LSPs are as well. 119 This document specifies a stateful PCEP extension to associate two or 120 more LSPs for the purpose of setting up path protection. The 121 proposed extension covers the following scenarios: 123 o A PCC initiates a protection LSP and retains the control of the 124 LSP. The PCC computes the path himself or make a request for path 125 computation to a PCE. After the path setup, it reports to the PCE 126 with the information and state of the path. This is the passive 127 stateful mode [RFC8051]. 129 o A PCC initiates a protection LSP and delegates the control of the 130 LSP to a stateful PCE. The PCE may compute the path for the LSP 131 and update the PCC with the information about the path as long as 132 it controls the LSP. This is the active stateful mode [RFC8051]. 134 o A protection LSP could be initiated by a stateful PCE, which 135 retains the control of the LSP. The PCE is responsible for 136 computing the path of the LSP and updating to the PCC with the 137 information about the path. This is the PCE Initiated mode 138 [I-D.ietf-pce-pce-initiated-lsp]. 140 Note that protection LSP can be established prior to the failure (in 141 which case the LSP is said to me in standby mode) or post failure of 142 the corresponding working LSP according to the operator choice/ 143 policy. 145 1.1. Requirements Language 147 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 148 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 149 document are to be interpreted as described in [RFC2119]. 151 2. Terminology 153 The following terminologies are used in this document: 155 ERO: Explicit Route Object. 157 LSP: Label Switched Path. 159 PCC: Path Computation Client. 161 PCE: Path Computation Element 163 PCEP: Path Computation Element Protocol. 165 PPAG: Path Protection Association Group. 167 TLV: Type, Length, and Value. 169 3. PCEP Extensions 171 3.1. Path Protection Association Type 173 LSPs are not associated by listing the other LSPs with which they 174 interact, but rather by making them belong to an association group 175 referred to as "Path Protection Association Group" (PPAG) in this 176 document. All LSPs join a PPAG individually. PPAG is based on the 177 generic Association object used to associate two or more LSPs 178 specified in [I-D.ietf-pce-association-group]. A member of a PPAG 179 can take the role of working or protection LSP. This document 180 defines a new association type called "Path Protection Association 181 Type" of value TBD1. A PPAG can have one working LSP and/or one or 182 more protection LSPs. The source and destination of all LSPs within 183 a PPAG MUST be the same. 185 The format of the Association object used for PPAG is specified in 186 [I-D.ietf-pce-association-group] and replicated in this document for 187 easy reference in Figure 1 and Figure 2. 189 0 1 2 3 190 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 1 191 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 192 | Reserved | Flags |R| 193 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 194 | Association type = TBD1 | Association | 195 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 196 | IPv4 Association Source | 197 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 198 // Optional TLVs // 199 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 201 Figure 1: PPAG IPv4 ASSOCIATION Object format 203 0 1 2 3 204 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 1 205 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 206 | Reserved | Flags |R| 207 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 208 | Association Type = TBD1 | Association | 209 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 210 | | 211 | IPv6 Association Source | 212 | | 213 | | 214 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 215 // Optional TLVs // 216 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 218 Figure 2: PPAG IPv6 ASSOCIATION Object format 220 This document defines a new Association type, the Path Protection 221 Association type, value will be assigned by IANA (TBD1). 223 This Association-Type is dynamic in nature and created by the PCC or 224 PCE for the LSPs originating at the same head node and terminating at 225 the same destination. These associations are conveyed via PCEP 226 messages to the PCEP peer. Operator-configured Association Range 227 SHOULD NOT be set for this association-type and MUST be ignored. 229 3.2. Path Protection Association TLV 231 The Path Protection Association TLV is an optional TLV for use with 232 the Path Protection Association Object Type. The Path Protection 233 Association TLV MUST NOT be present more than once. If it appears 234 more than once, only the first occurrence is processed and any others 235 MUST be ignored. 237 The Path Protection Association TLV follows the PCEP TLV format of 238 [RFC5440]. 240 The type (16 bits) of the TLV is to be assigned by IANA. The length 241 field is 16 bit-long and has a fixed value of 4. 243 The value comprises a single field, the Path Protection Association 244 Flags (32 bits), where each bit represents a flag option. 246 The format of the Path Protection Association TLV (Figure 3) is as 247 follows: 249 0 1 2 3 250 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 1 251 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 252 | Type = TBD2 | Length | 253 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 254 | Path Protection Association Flags |S|P| 255 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 257 Figure 3: Path Protection Association TLV format 259 P (PROTECTION-LSP 1 bit) - Indicates whether the LSP associated with 260 the PPAG is working or protection LSP. If this flag is set, the LSP 261 is a protection LSP. 263 S (STANDBY 1 bit)- When the P flag is set, the S flag indicates 264 whether the protection LSP associated with the PPAG is in standby 265 mode. The S flag is ignored if the P flag is not set. 267 If the Path Protection Association TLV is missing, it means the LSP 268 is the working LSP. 270 4. Operation 272 4.1. PCC Initiated LSPs 274 A PCC can associate a set of LSPs under its control for path 275 protection purpose. Similarly, the PCC can remove on or more LSPs 276 under its control from the corresponding PPAG. In both cases, the 277 PCC must report the change in association to PCE(s) via PCRpt 278 message. A PCC can also delegate the working and protection LSPs to 279 a stateful PCE, where PCE would control and update the paths and 280 attributes of the LSPs in the association group. 282 A stateless PCC can request protection to a PCE through PCReq 283 message. 285 4.2. PCE Initiated LSPs 287 A PCE can create/update working and protection LSPs independently. 288 As specified in [I-D.ietf-pce-association-group], Association Groups 289 can be created by both PCE and PCC. 291 A PCE can remove a protection LSP from a PPAG as specified in 292 [I-D.ietf-pce-association-group]. 294 4.3. State Synchronization 296 During state synchronization, a PCC MUST report all the existing path 297 protection association groups as well as any path protection flags to 298 PCE(s). Following the state synchronization, the PCE would remove 299 all stale information as per [I-D.ietf-pce-association-group]. 301 4.4. Error Handling 303 All LSPs (working or protection) within a PPAG MUST have the same 304 source and destination. If a PCE attempts to add an LSP to a PPAG 305 and the source and/or destination of the LSP is/are different from 306 the LSP(s) in the PPAG, the PCC MUST send PCErr with Error-Type= TBD 307 (Association Error) [I-D.ietf-pce-association-group] and Error-Value 308 = TBD3 (End points mismatch for Path Protection Association). 310 There MUST be only one working LSP within a PPAG. If a PCEP Speaker 311 attempts to add another working LSP, the PCEP peer MUST send PCErr 312 with Error-Type=TBD (Association Error) 313 [I-D.ietf-pce-association-group] and Error-Value = TBD4 (Attempt to 314 add another working LSP for Path Protection Association). 316 5. Other considerations 318 The diversity requirement for a group of LSPs is handled via another 319 association type called "Disjointness Association", as described in 320 [I-D.ietf-pce-association-diversity]. The diversity requirements for 321 the the protection LSP are also handled by including both ASSOCIATION 322 object for the group of LSPs. 324 6. IANA considerations 325 6.1. Association Type 327 This document defines a new association type, originally defined in 328 [I-D.ietf-pce-association-group], for path protection. IANA is 329 requested to make the assignment of a new value for the sub-registry 330 "ASSOCIATION Type Field" (request to be created in 331 [I-D.ietf-pce-association-group]), as follows: 333 +------------------------+------------------------+-----------------+ 334 | Association Type Value | Association Name | Reference | 335 +------------------------+------------------------+-----------------+ 336 | TBD1 (Suggested value | Path Protection | This | 337 | - 1) | Association | document | 338 +------------------------+------------------------+-----------------+ 340 6.2. PPAG TLV 342 This document defines a new TLV for carrying additional information 343 of LSPs within a path protection association group. IANA is 344 requested to make the assignment of a new value for the existing 345 "PCEP TLV Type Indicators" registry as follows: 347 +-----------------------+-----------------------------+-------------+ 348 | TLV Type Value | TLV Name | Reference | 349 +-----------------------+-----------------------------+-------------+ 350 | TBD2 (suggested Value | Path Protection Association | This | 351 | - 29) | Group TLV | document | 352 +-----------------------+-----------------------------+-------------+ 354 This document requests that a new sub-registry, named "Path 355 protection Association Group TLV Flag Field", is created within the 356 "Path Computation Element Protocol (PCEP) Numbers" registry to manage 357 the Flag field in the Path Protection Association Group TLV. New 358 values are to be assigned by Standards Action [RFC8126]. Each bit 359 should be tracked with the following qualities: 361 Each bit should be tracked with the following qualities: 363 o Bit number (count from 0 as the most significant bit) 365 o Name flag 367 o Reference 368 +------------+--------------------+----------------+ 369 | Bit Number | Name | Reference | 370 +------------+--------------------+----------------+ 371 | 31 | P - PROTECTION-LSP | This document | 372 | 30 | S - STANDBY | This document | 373 +------------+--------------------+----------------+ 375 Table 1: PPAG TLV 377 6.3. PCEP Errors 379 This document defines new Error-Type and Error-Value related to path 380 protection association. IANA is requested to allocate new error 381 values within the "PCEP-ERROR Object Error Types and Values" sub- 382 registry of the PCEP Numbers registry, as follows: 384 +------------+-------------------+----------------------------------+ 385 | Error-Type | Meaning | Reference | 386 +------------+-------------------+----------------------------------+ 387 | TBD | Association error | [I-D.ietf-pce-association-group] | 388 | | Error-value=TBD3: | This document | 389 | | End points | | 390 | | mismatch for Path | | 391 | | Protection | | 392 | | Association | | 393 | | Error-value=TBD4: | This document | 394 | | Attempt to add | | 395 | | another working | | 396 | | LSP for Path | | 397 | | Protection | | 398 | | Association | | 399 +------------+-------------------+----------------------------------+ 401 7. Security Considerations 403 The security considerations described in [I-D.ietf-pce-stateful-pce], 404 [I-D.ietf-pce-pce-initiated-lsp], and [RFC5440] apply to the 405 extensions described in this document as well. Additional 406 considerations related to associations where a malicious PCEP speaker 407 could be spoofed and could be used as an attack vector by creating 408 associations is described in [I-D.ietf-pce-association-group]. Thus 409 securing the PCEP session using Transport Layer Security (TLS) 410 [I-D.ietf-pce-pceps], as per the recommendations and best current 411 practices in [RFC7525], is RECOMMENDED. 413 8. Manageability Considerations 415 8.1. Control of Function and Policy 417 Mechanisms defined in this document do not imply any control or 418 policy requirements in addition to those already listed in [RFC5440], 419 [I-D.ietf-pce-stateful-pce], and [I-D.ietf-pce-pce-initiated-lsp]. 421 8.2. Information and Data Models 423 [RFC7420] describes the PCEP MIB, there are no new MIB Objects for 424 this document. 426 The PCEP YANG module [I-D.ietf-pce-pcep-yang] supports associations. 428 8.3. Liveness Detection and Monitoring 430 Mechanisms defined in this document do not imply any new liveness 431 detection and monitoring requirements in addition to those already 432 listed in [RFC5440], [I-D.ietf-pce-stateful-pce], and 433 [I-D.ietf-pce-pce-initiated-lsp]. 435 8.4. Verify Correct Operations 437 Mechanisms defined in this document do not imply any new operation 438 verification requirements in addition to those already listed in 439 [RFC5440], [I-D.ietf-pce-stateful-pce], and 440 [I-D.ietf-pce-pce-initiated-lsp]. 442 8.5. Requirements On Other Protocols 444 Mechanisms defined in this document do not imply any new requirements 445 on other protocols. 447 8.6. Impact On Network Operations 449 Mechanisms defined in this document do not have any impact on network 450 operations in addition to those already listed in [RFC5440], 451 [I-D.ietf-pce-stateful-pce], and [I-D.ietf-pce-pce-initiated-lsp]. 453 9. Acknowledgments 455 We would like to thank Jeff Tantsura and Xian Zhang for their 456 contributions to this document. 458 10. References 460 10.1. Normative References 462 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 463 Requirement Levels", BCP 14, RFC 2119, 464 DOI 10.17487/RFC2119, March 1997, 465 . 467 [RFC5440] Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation 468 Element (PCE) Communication Protocol (PCEP)", RFC 5440, 469 DOI 10.17487/RFC5440, March 2009, 470 . 472 [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for 473 Writing an IANA Considerations Section in RFCs", BCP 26, 474 RFC 8126, DOI 10.17487/RFC8126, June 2017, 475 . 477 [I-D.ietf-pce-stateful-pce] 478 Crabbe, E., Minei, I., Medved, J., and R. Varga, "PCEP 479 Extensions for Stateful PCE", draft-ietf-pce-stateful- 480 pce-21 (work in progress), June 2017. 482 [I-D.ietf-pce-pce-initiated-lsp] 483 Crabbe, E., Minei, I., Sivabalan, S., and R. Varga, "PCEP 484 Extensions for PCE-initiated LSP Setup in a Stateful PCE 485 Model", draft-ietf-pce-pce-initiated-lsp-10 (work in 486 progress), June 2017. 488 [I-D.ietf-pce-association-group] 489 Minei, I., Crabbe, E., Sivabalan, S., Ananthakrishnan, H., 490 Dhody, D., and Y. Tanaka, "PCEP Extensions for 491 Establishing Relationships Between Sets of LSPs", draft- 492 ietf-pce-association-group-03 (work in progress), June 493 2017. 495 10.2. Information References 497 [RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation 498 Element (PCE)-Based Architecture", RFC 4655, 499 DOI 10.17487/RFC4655, August 2006, 500 . 502 [RFC4657] Ash, J., Ed. and J. Le Roux, Ed., "Path Computation 503 Element (PCE) Communication Protocol Generic 504 Requirements", RFC 4657, DOI 10.17487/RFC4657, September 505 2006, . 507 [RFC7420] Koushik, A., Stephan, E., Zhao, Q., King, D., and J. 508 Hardwick, "Path Computation Element Communication Protocol 509 (PCEP) Management Information Base (MIB) Module", 510 RFC 7420, DOI 10.17487/RFC7420, December 2014, 511 . 513 [RFC7525] Sheffer, Y., Holz, R., and P. Saint-Andre, 514 "Recommendations for Secure Use of Transport Layer 515 Security (TLS) and Datagram Transport Layer Security 516 (DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May 517 2015, . 519 [RFC8051] Zhang, X., Ed. and I. Minei, Ed., "Applicability of a 520 Stateful Path Computation Element (PCE)", RFC 8051, 521 DOI 10.17487/RFC8051, January 2017, 522 . 524 [I-D.ietf-pce-pceps] 525 Lopez, D., Dios, O., Wu, Q., and D. Dhody, "Secure 526 Transport for PCEP", draft-ietf-pce-pceps-14 (work in 527 progress), May 2017. 529 [I-D.ietf-pce-pcep-yang] 530 Dhody, D., Hardwick, J., Beeram, V., and j. 531 jefftant@gmail.com, "A YANG Data Model for Path 532 Computation Element Communications Protocol (PCEP)", 533 draft-ietf-pce-pcep-yang-03 (work in progress), June 2017. 535 [I-D.ietf-pce-association-diversity] 536 Litkowski, S., Sivabalan, S., Barth, C., and D. Dhody, 537 "Path Computation Element communication Protocol extension 538 for signaling LSP diversity constraint", draft-ietf-pce- 539 association-diversity-01 (work in progress), March 2017. 541 Authors' Addresses 543 Hariharan Ananthakrishnan 544 Packet Design 545 1 South Almaden Blvd, #1150, 546 San Jose, CA, 95113 547 USA 549 EMail: hari@packetdesign.com 550 Siva Sivabalan 551 Cisco 552 2000 Innovation Drive 553 Kananta, Ontaria K2K 3E8 554 Cananda 556 EMail: msiva@cisco.com 558 Colby Barth 559 Juniper Networks 560 1194 N Mathilda Ave, 561 Sunnyvale, CA, 94086 562 USA 564 EMail: cbarth@juniper.net 566 Raveendra Torvi 567 Juniper Networks 568 1194 N Mathilda Ave, 569 Sunnyvale, CA, 94086 570 USA 572 EMail: rtorvi@juniper.net 574 Ina Minei 575 Google, Inc 576 1600 Amphitheatre Parkway 577 Mountain View, CA, 94043 578 USA 580 EMail: inaminei@google.com 582 Edward Crabbe 583 Individual Contributor 585 EMail: edward.crabbe@gmail.com 586 Dhruv Dhody 587 Huawei Technologies 588 Divyashree Techno Park, Whitefield 589 Bangalore, Karnataka 560066 590 India 592 EMail: dhruv.ietf@gmail.com