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Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year == Using lowercase 'not' together with uppercase 'MUST', 'SHALL', 'SHOULD', or 'RECOMMENDED' is not an accepted usage according to RFC 2119. Please use uppercase 'NOT' together with RFC 2119 keywords (if that is what you mean). Found 'MUST not' in this paragraph: Note that[I-D.ietf-lsr-flex-algo].also allows user to define other algorithm values, i.e., FA-id within [128, 255], for the purpose of constraint based path computation. However, an FA-id algorithm value MUST not be set in this field, the reason is that FA-id has not semantic local within AII. -- The document date (December 01, 2019) is 1606 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) -- Looks like a reference, but probably isn't: '128' on line 275 -- Looks like a reference, but probably isn't: '255' on line 275 == Unused Reference: 'RFC2119' is defined on line 486, but no explicit reference was found in the text == Outdated reference: A later version (-26) exists of draft-ietf-lsr-flex-algo-05 ** Obsolete normative reference: RFC 5316 (Obsoleted by RFC 9346) == Outdated reference: A later version (-04) exists of draft-peng-teas-network-slicing-01 Summary: 3 errors (**), 0 flaws (~~), 5 warnings (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Networking Working Group Yongqing. Zhu 3 Internet-Draft China Telecom 4 Intended status: Standards Track Ran. Chen 5 Expires: June 3, 2020 Shaofu. Peng 6 ZTE Corporation 7 Fengwei. Qin 8 China Mobile 9 December 01, 2019 11 IS-IS Extensions to Support Packet Network Slicing using Segment Routing 12 draft-zch-lsr-isis-network-slicing-03 14 Abstract 16 [I-D.peng-teas-network-slicing] defines a unified TN-slice 17 identifier, AII(administrative instance identifier), to indicate the 18 topology, computing, storage resources of the dedicated virtual 19 network for both intra-domain and inter-domain network slicing 20 scenarios. This draft describes the IS-IS extensions required to 21 support Packet Network Slicing using Segment Routing. 23 Status of This Memo 25 This Internet-Draft is submitted in full conformance with the 26 provisions of BCP 78 and BCP 79. 28 Internet-Drafts are working documents of the Internet Engineering 29 Task Force (IETF). Note that other groups may also distribute 30 working documents as Internet-Drafts. The list of current Internet- 31 Drafts is at https://datatracker.ietf.org/drafts/current/. 33 Internet-Drafts are draft documents valid for a maximum of six months 34 and may be updated, replaced, or obsoleted by other documents at any 35 time. It is inappropriate to use Internet-Drafts as reference 36 material or to cite them other than as "work in progress." 38 This Internet-Draft will expire on June 3, 2020. 40 Copyright Notice 42 Copyright (c) 2019 IETF Trust and the persons identified as the 43 document authors. All rights reserved. 45 This document is subject to BCP 78 and the IETF Trust's Legal 46 Provisions Relating to IETF Documents 47 (https://trustee.ietf.org/license-info) in effect on the date of 48 publication of this document. Please review these documents 49 carefully, as they describe your rights and restrictions with respect 50 to this document. Code Components extracted from this document must 51 include Simplified BSD License text as described in Section 4.e of 52 the Trust Legal Provisions and are provided without warranty as 53 described in the Simplified BSD License. 55 Table of Contents 57 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 58 2. Conventions used in this document . . . . . . . . . . . . . . 3 59 3. Router Capabilities for TN-slice Identifier . . . . . . . . . 3 60 4. Advertising TN-slice Identifier as a new TE parameter of a 61 link . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 62 5. Advertising TN-slice Identifier for L2 Bundle Member . . . . 5 63 6. Advertising prefix-SID per TN-slice Identifier . . . . . . . 5 64 7. Advertising Adjacency-SID per TN-slice Identifier . . . . . . 7 65 8. Advertising Adjacency-SID per TN-slice Identifier in LANs . . 8 66 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 67 9.1. Router Capabilities for TN-slice Identifier . . . . . . . 10 68 9.2. TN-slice Identifier list sub-TLV . . . . . . . . . . . . 10 69 9.3. L2 Bundle Member TN-Slice Identifier sub-TLV . . . . . . 10 70 9.4. Prefix-SID for TN-slice Identifier sub-TLV . . . . . . . 10 71 9.5. Adjacency-SID for TN-slice Identifier sub-TLV . . . . . . 10 72 9.6. LAN-Adj-SID for TN-slice Identifier sub-TLV . . . . . . . 11 73 10. Security Considerations . . . . . . . . . . . . . . . . . . . 11 74 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11 75 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 76 12.1. Normative references . . . . . . . . . . . . . . . . . . 11 77 12.2. Informative references . . . . . . . . . . . . . . . . . 12 78 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12 80 1. Introduction 82 For a packet network, network slicing requires the underlying network 83 to support partitioning of the network resources to provide the 84 client with dedicated (private) networking, computing, and storage 85 resources drawn from a shared pool. [I-D.peng-teas-network-slicing] 86 defines a unified TN-slice identifier, AII(administrative instance 87 identifier), to indicate the topology, computing, storage resources 88 of the dedicated virtual network for both intra-domain and inter- 89 domain network slicing scenarios, and how to compute SR-BE or SR-TE 90 path according to TN-slice Identifier combined with other creteria. 92 This draft describes the IS-IS extensions required to distribute TN- 93 slice Identifier(that is AII) information in an AS. 95 2. Conventions used in this document 97 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 98 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 99 document are to be interpreted as described in RFC2119. 101 3. Router Capabilities for TN-slice Identifier 103 Although a router can deduce which TN-slices it has participated in 104 according to the AII configuration of all links, an ISIS instance can 105 explicitly control which TN-slices it wants to enable (or join), to 106 explicitly control which SPT (shortest path tree) for a specific AII 107 to be created. It is possible for a route process not to join any 108 TN-slices (except the default AII 0) in despite of any AII 109 configuration of any links. Especially, it is hard to deduce the 110 participated TN-slice according to the AII configuration of L2 Bundle 111 Member. 113 This section defines AII Participation sub-TLV which is inserted into 114 the IS-IS Router Capability TLV-242 that is defined in [RFC7981], to 115 explicitly advertise which TN-slice a router wants to take part in. 117 The TN-slice identifier Participation sub-TLV has the following 118 format: 120 0 1 2 3 121 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 1 122 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 123 | Type=TBD1 | Length | Number | | 124 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 125 | AII for virtual networks 1 | 126 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 127 | ...... | 128 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 129 | AII for virtual networks N | 130 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 132 Figure 1 134 where: 136 Type: TBD1 (Suggested value to be assigned by IANA) 138 Length: variable. 140 Number:Number of virtual networks. 142 AII for VN: allocate different TN-slice identifier (AII) for 143 different virtual networks. AII is used to distinguish different 144 virtual network resources. 146 4. Advertising TN-slice Identifier as a new TE parameter of a link 148 [RFC5305] describes extensions to the Intermediate System to 149 Intermediate System (IS-IS) protocol to support Traffic Engineering 150 (TE). 152 TN-slice Identifier can be used to color links to partition underlay 153 resource. This document defines a new extension of the existing IGP- 154 TE mechanisms[RFC5305] to distribute TN-slice Identifier information 155 in an AS as a new TE parameter of a link. 157 The TN-slice Identifier list sub-TLV has the following format: 159 0 1 2 3 160 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 1 161 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 162 | Type=TBD2 | Length | Reserved | Number | 163 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 164 | AII for virtual networks 1 | 165 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 166 | ...... | 167 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 168 | AII for virtual networks N | 169 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 171 Figure 2 173 Type: TBD2 (Suggested value to be assigned by IANA) 175 Length: variable. 177 Number:Number of virtual networks. 179 AII for VN: allocate different TN-slice identifier (AII) for 180 different virtual networks. AII is used to distinguish different 181 virtual network resources. 183 This sub-TLV MAY be present in any of the following TLVs: 185 TLV-22 (Extended IS reachability) [RFC5305]. 187 TLV-222 (Multitopology IS)[RFC5120]. 189 TLV-23 (IS Neighbor Attribute)[RFC5311]. 191 TLV-223 (Multitopology IS Neighbor Attribute)[RFC5311]. 193 TLV-141 (inter-AS reachability information)[RFC5316]. 195 This sub-TLV SHOULD appear once at most in each TLV. Indicates that 196 a link MAY belong to multiple virtual networks. 198 Note that AII 0 does not require notification, and all links are 199 always in AII 0 at the same time. 201 5. Advertising TN-slice Identifier for L2 Bundle Member 203 [I-D.ietf-isis-l2bundles] defines a sub-TLV of L2 Bundle Attribute 204 Descriptors, and the sub-TLV may define an attribute common to all of 205 the bundle members listed or a sub-TLV may define an attribute unique 206 to each bundle member. This document defines a new sub-TLV: L2 207 Bundle Member TN-Slice Identifier sub-TLV. 209 This sub-TLV is used to advertise TN-slice Identifier for L2 Bundle 210 Member associated with a parent L3 adjacency which is Point-to- 211 Point.The following format is defined for this sub-TLV: 213 Type: TBD3. 215 Length: variable 217 L2 Bundle Member TN-slice Identifier.There MUST be one TN-slice 218 Identifier(AII) for each of the L2 Bundle Members advertised under 219 the preceding L2 Bundle Member Attribute Descriptor. 221 This sub-TLV MAY be present in the following TLVs: 223 TLV-25 (L2 Bundle Member Attributes) [I-D.ietf-isis-l2bundles]. 225 This sub-TLV SHOULD appear once at most in the TLV. Indicates that 226 the TN-slice Identifier for L2 Bundle Member. 228 6. Advertising prefix-SID per TN-slice Identifier 230 [I-D.ietf-isis-segment-routing-extensions] defines a new IS-IS sub- 231 TLV: the Prefix Segment Identifier sub-TLV (Prefix-SID sub-TLV). The 232 Prefix-SID sub-TLV carries the Segment Routing IGP-Prefix-SID as 233 defined in [RFC8402], and is associated to a prefix advertised by a 234 node. 236 To distinguish forwarding behavior of different virtual networks, 237 Prefix-SID need to be allocated per TN-slice Identifier and 238 advertised in the IGP domain. This document defines a new extension 239 of the existing Prefix-SID sub-TLV. 241 The Prefix-SID for TN-slice Identifier sub-TLV has the following 242 format: 244 0 1 2 3 245 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 1 246 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 247 | Type=TBD4 | Length | Flag | Algorithm | 248 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 249 | AII | 250 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 251 | SID/Index/Label(Variable) | 252 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 254 Figure 3 256 where: 258 Type:TBD4 (Suggested value to be assigned by IANA) 260 Length: Variable. Depending on the size of the SID. 262 The "Flags" and "SID/Index/Label" fields are the same as the Prefix- 263 SID sub-TLV [I-D.ietf-isis-segment-routing-extensions]. 265 Algorithm: Accoridng to section "3.2. SR-Algorithm Sub-TLV" of 266 >[I-D.ietf-isis-segment-routing-extensions], two values can be set in 267 this field. 269 o 0: Shortest Path First (SPF) algorithm based on link metric. 271 o 1: Strict Shortest Path First (SPF) algorithm based on link 272 metric. 274 Note that[I-D.ietf-lsr-flex-algo].also allows user to define other 275 algorithm values, i.e., FA-id within [128, 255], for the purpose of 276 constraint based path computation. However, an FA-id algorithm value 277 MUST not be set in this field, the reason is that FA-id has not 278 semantic local within AII. 280 AII: Identifies the TN-slice (AII) information corresponding to the 281 Prefix-SID. 283 This sub-TLV MAY be present in any of the following TLVs: 285 TLV-135 (Extended IPv4 reachability) defined in [RFC5305]. 287 TLV-235 (Multitopology IPv4 Reachability) defined in [RFC5120]. 289 TLV-236 (IPv6 IP Reachability) defined in [RFC5308]. 291 TLV-237 (Multitopology IPv6 IP Reachability) defined in [RFC5120]. 293 This sub-TLV MAY appear multiple times in each TLV. 295 7. Advertising Adjacency-SID per TN-slice Identifier 297 [I-D.ietf-isis-segment-routing-extensions]defines the IS-IS sub-TLV: 298 the Adjacency Segment Identifier sub-TLV (Adj-SID sub-TLV).The Adj- 299 SID sub-TLV is an optional sub-TLV carrying the Segment Routing IGP- 300 Adjacency-SID as defined in [RFC8402]. 302 To distinguish forwarding behavior of different virtual networks, 303 Adjacency-SID need to be allocated per TN-slice Identifier and 304 advertised in the IGP domain. This document defines a new extension 305 of the existing Adjacency-SID sub-TLV. 307 The Adjacency-SID for TN-slice Identifier sub-TLV has the following 308 format: 310 0 1 2 3 311 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 1 312 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 313 | Type=TBD5 | Length | Flag | Algorithm | 314 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 315 | AII | 316 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 317 | SID/Index/Label(Variable) | 318 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 320 Figure 4 322 where: 324 Type:TBD5(Suggested value to be assigned by IANA) 326 Length: Variable. Depending on the size of the SID. 328 The "Flags" and "SID/Index/Label" fields are the same as the 329 Adjacency-SID sub-TLV [I-D.ietf-isis-segment-routing-extensions]. 331 AII: Identifies the TN-slice (AII) information corresponding to the 332 Adjacency-SID. 334 This sub-TLV MAY be present in any of the following TLVs: 336 TLV-22 (Extended IS reachability) [RFC5305]. 338 TLV-222 (Multitopology IS)[RFC5120]. 340 TLV-23 (IS Neighbor Attribute)[RFC5311]. 342 TLV-223 (Multitopology IS Neighbor Attribute)[RFC5311]. 344 TLV-141 (inter-AS reachability information)[RFC5316]. 346 Multiple Adj-SID sub-TLVs MAY be associated with a single IS- 347 neighbor. This sub-TLV MAY appear multiple times in each TLV. 349 8. Advertising Adjacency-SID per TN-slice Identifier in LANs 351 In LAN subnetworks,[I-D.ietf-isis-segment-routing-extensions]defines 352 the LAN-Adj-SID sub-TLV for a router to advertise the Adj-SID of each 353 of its neighbors. 355 To distinguish forwarding behavior of different virtual networks, 356 Adjacency-SID need to be allocated per TN-slice Identifier and 357 advertised in the IGP domain. This document defines a new extension 358 of the existing Adjacency-SID sub-TLV. 360 The LAN-Adj-SID for TN-slice Identifier sub-TLV has the following 361 format: 363 0 1 2 3 364 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 1 365 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 366 | Type=TBD6 | Length | Flags | Weight | 367 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 369 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 370 | Neighbor System-ID (ID length octets) | 371 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 372 | | 373 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 374 | AII | 375 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 376 | SID/Label/Index (variable) | 377 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 379 Figure 5 381 where: 383 Type:TBD6 (Suggested value to be assigned by IANA) 385 Length: Variable. Depending on the size of the SID. 387 The "Flags" and "SID/Index/Label" fields are the same as the 388 Adjacency-SID sub-TLV [I-D.ietf-isis-segment-routing-extensions]. 390 AII: Identifies the TN-slice (AII) information corresponding to the 391 Adjacency-SID. 393 This sub-TLV MAY be present in any of the following TLVs: 395 TLV-22 (Extended IS reachability) [RFC5305]. 397 TLV-222 (Multitopology IS)[RFC5120]. 399 TLV-23 (IS Neighbor Attribute)[RFC5311]. 401 TLV-223 (Multitopology IS Neighbor Attribute)[RFC5311]. 403 Multiple Adj-SID sub-TLVs MAY be associated with a single IS- 404 neighbor. This sub-TLV MAY appear multiple times in each TLV. 406 9. IANA Considerations 408 This document requests allocation for the following Sub-TLVs. 410 9.1. Router Capabilities for TN-slice Identifier 412 This document requests IANA to assign a new code point in the "sub- 413 TLV for TLV 242" registry. 415 Type: TBD1 417 9.2. TN-slice Identifier list sub-TLV 419 This TLV shares sub-TLV space with existing "Sub-TLVs for TLVs 22, 420 222, 23,223 and 141 registry". 422 Type:TBD2(to be assigned by IANA). 424 9.3. L2 Bundle Member TN-Slice Identifier sub-TLV 426 This TLV shares sub-TLV space with existing "Sub-TLVs for TLVs 22, 427 222, 23, 25, 223 and 141 registry. 429 Type:TBD3(to be assigned by IANA). 431 This sub-TLV is allowed in the following TLVs: 433 22 23 25 141 222 223 434 n n y n n n 436 9.4. Prefix-SID for TN-slice Identifier sub-TLV 438 This TLV shares sub-TLV space with existing "Sub-TLVs for TLVs 439 135,235,226 and 237 registry". 441 Type:TBD4(to be assigned by IANA). 443 9.5. Adjacency-SID for TN-slice Identifier sub-TLV 445 This TLV shares sub-TLV space with existing "Sub-TLVs for TLVs 22, 446 222, 23,223 and 141 registry". 448 Type:TBD5(to be assigned by IANA). 450 9.6. LAN-Adj-SID for TN-slice Identifier sub-TLV 452 This TLV shares sub-TLV space with existing "Sub-TLVs for TLVs 22, 453 222, 23, and 223registry". 455 Type:TBD6(to be assigned by IANA). 457 10. Security Considerations 459 TBD. 461 11. Acknowledgements 463 TBD. 465 12. References 467 12.1. Normative references 469 [I-D.ietf-isis-l2bundles] 470 Ginsberg, L., Bashandy, A., Filsfils, C., Nanduri, M., and 471 E. Aries, "Advertising L2 Bundle Member Link Attributes in 472 IS-IS", draft-ietf-isis-l2bundles-07 (work in progress), 473 May 2017. 475 [I-D.ietf-isis-segment-routing-extensions] 476 Previdi, S., Ginsberg, L., Filsfils, C., Bashandy, A., 477 Gredler, H., and B. Decraene, "IS-IS Extensions for 478 Segment Routing", draft-ietf-isis-segment-routing- 479 extensions-25 (work in progress), May 2019. 481 [I-D.ietf-lsr-flex-algo] 482 Psenak, P., Hegde, S., Filsfils, C., Talaulikar, K., and 483 A. Gulko, "IGP Flexible Algorithm", draft-ietf-lsr-flex- 484 algo-05 (work in progress), November 2019. 486 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 487 Requirement Levels", BCP 14, RFC 2119, 488 DOI 10.17487/RFC2119, March 1997, 489 . 491 [RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi 492 Topology (MT) Routing in Intermediate System to 493 Intermediate Systems (IS-ISs)", RFC 5120, 494 DOI 10.17487/RFC5120, February 2008, 495 . 497 [RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic 498 Engineering", RFC 5305, DOI 10.17487/RFC5305, October 499 2008, . 501 [RFC5308] Hopps, C., "Routing IPv6 with IS-IS", RFC 5308, 502 DOI 10.17487/RFC5308, October 2008, 503 . 505 [RFC5311] McPherson, D., Ed., Ginsberg, L., Previdi, S., and M. 506 Shand, "Simplified Extension of Link State PDU (LSP) Space 507 for IS-IS", RFC 5311, DOI 10.17487/RFC5311, February 2009, 508 . 510 [RFC5316] Chen, M., Zhang, R., and X. Duan, "ISIS Extensions in 511 Support of Inter-Autonomous System (AS) MPLS and GMPLS 512 Traffic Engineering", RFC 5316, DOI 10.17487/RFC5316, 513 December 2008, . 515 [RFC7981] Ginsberg, L., Previdi, S., and M. Chen, "IS-IS Extensions 516 for Advertising Router Information", RFC 7981, 517 DOI 10.17487/RFC7981, October 2016, 518 . 520 [RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L., 521 Decraene, B., Litkowski, S., and R. Shakir, "Segment 522 Routing Architecture", RFC 8402, DOI 10.17487/RFC8402, 523 July 2018, . 525 12.2. Informative references 527 [I-D.peng-teas-network-slicing] 528 Peng, S., Chen, R., Mirsky, G., and F. Qin, "Packet 529 Network Slicing using Segment Routing", draft-peng-teas- 530 network-slicing-01 (work in progress), November 2019. 532 Authors' Addresses 534 Yongqing Zhu 535 China Telecom 537 Email: zhuyq.gd@chinatelecom.cn 539 Ran Chen 540 ZTE Corporation 542 Email: chen.ran@zte.com.cn 543 Shaofu Peng 544 ZTE Corporation 546 Email: peng.shaofu@zte.com.cn 548 Fengwei Qin 549 China Mobile 551 Email: qinfengwei@chinamobile.com