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Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (23 February 2022) is 794 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(See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Outdated reference: A later version (-07) exists of draft-ietf-bier-ospfv3-extensions-05 Summary: 0 errors (**), 0 flaws (~~), 3 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group S. Dhanaraj, Ed. 3 Internet-Draft G. Yan, Ed. 4 Updates: 8296 (if approved) Huawei 5 Intended status: Standards Track IJ. Wijnands 6 Expires: 27 August 2022 P. Psenak 7 Cisco Systems, Inc. 8 Z. Zhang 9 Juniper Networks. 10 J. Xie 11 Huawei 12 23 February 2022 14 LSR Extensions for BIER over Ethernet 15 draft-ietf-bier-lsr-ethernet-extensions-04 17 Abstract 19 Bit Index Explicit Replication (BIER) is an architecture that 20 provides multicast forwarding through a "BIER domain" without 21 requiring intermediate routers to maintain multicast related per-flow 22 state. BIER can be supported in MPLS and non-MPLS networks. 24 This document specifies the required extensions to the IS-IS, OSPFv2 25 and OSPFv3 protocols for supporting BIER in non-MPLS networks using 26 BIER in Ethernet encapsulation. 28 Status of This Memo 30 This Internet-Draft is submitted 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 https://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 27 August 2022. 45 Copyright Notice 47 Copyright (c) 2022 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 (https://trustee.ietf.org/ 52 license-info) in effect on the date of publication of this document. 53 Please review these documents carefully, as they describe your rights 54 and restrictions with respect to this document. Code Components 55 extracted from this document must include Revised BSD License text as 56 described in Section 4.e of the Trust Legal Provisions and are 57 provided without warranty as described in the Revised BSD License. 59 Table of Contents 61 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 62 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 63 2.1. Requirements Language . . . . . . . . . . . . . . . . . . 5 64 3. Specification . . . . . . . . . . . . . . . . . . . . . . . . 5 65 3.1. IS-IS BIER Ethernet Encapsulation Sub-sub TLV . . . . . . 5 66 3.2. OSPFv2 BIER Ethernet Encapsulation Sub-TLV . . . . . . . 7 67 3.3. OSPFv3 BIER Ethernet Encapsulation Sub-TLV . . . . . . . 8 68 4. Security Considerations . . . . . . . . . . . . . . . . . . . 10 69 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 70 5.1. IS-IS sub-sub-TLVs for BIER Info sub-TLV Registry . . . . 10 71 5.2. OSPFv2 Extended Prefix TLV Sub-TLVs Registry . . . . . . 10 72 5.3. OSPFv3 Extended LSA Sub-TLVs Registry . . . . . . . . . . 10 73 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 11 74 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 75 7.1. Normative References . . . . . . . . . . . . . . . . . . 11 76 7.2. Informative References . . . . . . . . . . . . . . . . . 11 77 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13 79 1. Introduction 81 Bit Index Explicit Replication (BIER) [RFC8279] is an architecture 82 that provides multicast forwarding through a "BIER domain" without 83 requiring intermediate routers to maintain multicast related per-flow 84 state. BIER can be supported in MPLS and non-MPLS networks. 86 [RFC8296] specifies a common BIER header format for both MPLS and 87 non-MPLS networks, though the first 20-bits of the BIER header 88 (referred as BIFT-id) is a "MPLS Label" in case of MPLS networks and 89 is a "domain-wide-unique-value" representing the combination of SD- 90 BSL-SI in case of non-MPLS networks. 91 [I-D.ietf-bier-non-mpls-bift-encoding] specifies two optional ways of 92 statically assigning domain-wide-unique mapping between BIFT-id's and 93 SD-BSL-SI combination. 95 However, BIER architecture [RFC8279] does not require domain-wide- 96 unique BIFT-id's to be used (even for non-MPLS encapsulation). As 97 discussed in [I-D.zzhang-bier-rift], the BIFT-id in case of non-MPLS 98 encapsulation can also just be a local 20-bit opaque value and 99 signaled just like in MPLS case. This doucment updates section 100 2.2.1.1 of [RFC8296] that the BIFT-id for a SD-BSL-SI in case of non- 101 MPLS encapsulation need not be unique through out the BIER domain. 102 In such a case when the BIFT-id is not unique, the BIFT-id in the 103 packet is expected to change as the packet travels. 105 As an example, suppose a particular BIER domain contains a SD (SD 0), 106 supports two BSLs (256 and 512), and contains 1024 BFRs. A BFR that 107 is provisioned for above SD, and that supports both BSLs, could 108 advertise the following set of BIFT-id's: 110 BIFT-id 1: corresponding to SD 0, BSL 256, SI 0. 112 BIFT-id 2: corresponding to SD 0, BSL 256, SI 1. 114 BIFT-id 3: corresponding to SD 0, BSL 256, SI 2. 116 BIFT-id 4: corresponding to SD 0, BSL 256, SI 3. 118 BIFT-id 5: corresponding to SD 0, BSL 512, SI 0. 120 BIFT-id 6: corresponding to SD 0, BSL 512, SI 1. 122 Notice that the example uses ranges of continuous BIFT-id's: 124 BIFT-id range [1 to 4] correspond to . The first 125 BIFT-id in the range correspond to SI=0, the second correspond to 126 SI=1, and so on. 128 BIFT-id range [5 to 6] correspond to . The first 129 BIFT-id in the range correspond to SI=0, the second correspond to 130 SI=1. 132 Strictly speaking, using contiguous range is not required, but it is 133 done for the purpose of simplified signaling similar to MPLS label 134 blocks (notice that locally assigning BIFT-id ranges requires no 135 manual processing just like in the case of MPLS label block 136 allocation). 138 Processing and forwarding of BIER packets requires special software 139 and hardware capabilities. The BFRs supporting a BIER encapsulation 140 type MUST advertise this capability (along with the other required 141 parameters specific to the encapsulation) to the other routers in 142 BIER domain. This advertisement, for example, will enable the other 143 BFRs in the BIER domain in deciding, whether to include or exclude 144 the advertising router from the BAR and/or IPA algorithm while 145 computing the multicast path for a specific encapsulation type. 147 [RFC8401], [RFC8444] and [I-D.ietf-bier-ospfv3-extensions] specifies 148 the required extensions to the IS-IS [RFC1195], OSPFv2 [RFC2328] and 149 OSPFv3 [RFC8362] protocols respectively for the distribution of BIER 150 sub-domain information including the Sub-sub-TLV required to support 151 BIER in MPLS encapsulation for MPLS networks. 153 This document specifies the required extensions to the IS-IS 154 [RFC1195], OSPFv2 [RFC2328] and OSPFv3 [RFC8362] protocols for 155 supporting BIER using BIER in Ethernet encapsulation with dynamically 156 and locally assigned BIFT-id's. 158 Support for other encapsulation types are outside the scope of this 159 document. 161 2. Terminology 163 Some of the terminology specified in [RFC8279] is replicated here and 164 extended by necessary definitions: 166 BIER: Bit Index Explicit Replication 168 (The overall architecture of forwarding multicast using a Bit 169 Position). 171 BIER-MPLS: BIER in MPLS encapsulation. 173 (Encapsulation of BIER header inside MPLS header in MPLS 174 networks). 176 BIER-ETH: BIER in Ethernet encapsulation. 178 (Encapsulation of BIER header inside Ethernet header 179 (EtherType=0xAB37) in non-MPLS networks). 181 BFR: Bit Forwarding Router (A router that participates in Bit Index 183 Multipoint Forwarding). A BFR is identified by a unique BFR- 184 prefix in a BIER domain. 186 BIFT: Bit Index Forwarding Table used to forward the BIER packets in 187 a domain. 189 BAR: BIER Algorithm. Used to calculate underlay nexthops 191 as defined by the BAR value. 193 IPA: IGP Algorithm. May be used to modify, enhance or replace the 194 calculation of underlay paths as defined by the BAR value 196 SD: BIER sub-domain 198 2.1. Requirements Language 200 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 201 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 202 "OPTIONAL" in this document are to be interpreted as described in BCP 203 14 [RFC2119] [RFC8174] when, and only when, they appear in all 204 capitals, as shown here. 206 3. Specification 208 A BIER sub-domain MAY support multiple BIER encapsulation types like 209 BIER-MPLS, BIER-ETH. The different encapsulation types supported by 210 a BFR in a sub-domain MUST share the same BFR-id. This would allow 211 the BFR's in transit to translate the encapsulation from one type to 212 the other while forwarding the packet in the BIER sub-domain. 214 When a BFIR/BFR supports multiple BIER encapsulation types, when 215 sending to a BIER neighbor it MUST use a type that the neighbor also 216 supports. If the neighbor also supports more than one encapsulation 217 type that this BFIR/BFR supports, the type selection could be a 218 matter of local policy and is outside the scope of this document. 220 3.1. IS-IS BIER Ethernet Encapsulation Sub-sub TLV 222 BIER Info sub-TLV defined in [RFC8401] is used to advertise the sub- 223 domain id, and other associated parameters of the sub-domain like 224 BFR-id, MT, BAR, IPA. 226 This document introduces new sub-sub-TLV under BIER Info sub-TLV to 227 advertise the ethernet encapsulation capability and other associated 228 parameters of the encapsulation. 230 This sub-sub-TLV carries the information for the BIER Ethernet 231 encapsulation including the BitString length supported for a certain 232 pair. 234 It is advertised within the BIER Info sub-TLV defined in [RFC8401] 235 which in-turn is carried within the TLVs 235, 237 [RFC5120] or TLVs 236 135 [RFC5305], or TLV 236 [RFC5308]. 238 This sub-sub-TLV MAY appear multiple times within a single BIER Info 239 sub-TLV. If the same BitString length is repeated in multiple BIER 240 Ethernet encapsulation sub-sub-TLVs inside the same BIER Info sub- 241 TLV, the BIER Info sub-TLV MUST be ignored. 243 0 1 2 3 244 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 1 245 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 246 | Type | Length | 247 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 248 | Max SI |BS Len | BIFT-id | 249 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 251 Type: TBD1 (To be assigned by IANA). 253 Length: 4 255 Max SI: A 1 octet field encoding the Maximum Set Identifier 256 (Section 1 of [RFC8279]) used in the encapsulation for this BIER 257 subdomain for this BitString length. The first BIFT-id is for SI=0, 258 the second BIFT-id is for SI=1, etc. If the BIFT-id associated with 259 the Maximum Set Identifier exceeds the 20-bit range, the sub-sub-TLV 260 MUST be ignored. 262 Local BitString Length (BS Len): A 4 bit field encoding the 263 bitstring length (as per [RFC8296]) supported for the encapsulation. 265 BIFT-id: A 20 bit field encoding the first BIFT-id of the BIFT-id 266 range. 267 The "BIFT-id range" is the set of 20-bit values beginning with the 268 BIFT-id and ending with (BIFT-id + (Max SI)). These BIFT-id's are 269 used for BIER forwarding as described in [RFC8279] and [RFC8296]. 270 The size of the BIFT-id range is determined by the number of SI's 271 (Section 1 of [RFC8279]) that are used in the network. Each SI maps 272 to a single BIFT-id in the BIFT-id range: the first BIFT-id is for 273 SI=0, the second BIFT-id is for SI=1, etc. 274 If the BIFT-id associated with the Maximum Set Identifier exceeds 275 the 20-bit range, the BIER Ethernet Encapsulation Sub-sub-TLV 276 containing the error MUST be ignored. 277 BIFT-id ranges within all the BIER Ethernet Encapsulation sub-sub- 278 TLVs advertised by the same BFR MUST NOT overlap. If the overlap is 279 detected, the advertising router MUST be treated as if it did not 280 advertise any BIER Ethernet encapsulation sub-sub-TLVs. However the 281 BIFT-id ranges may overlap across different encapsulation types and 282 is allowed. As an example, the BIFT-id value in the Ethernet 283 encapsulation sub-sub-TLV may overlap with the Label value in the 284 Label range in BIER MPLS encapsulation sub-sub-TLV ([RFC8401] and is 285 allowed. 287 3.2. OSPFv2 BIER Ethernet Encapsulation Sub-TLV 289 BIER Sub-TLV defined in [RFC8444] is used to advertise the sub-domain 290 id, and other associated parameters of the sub-domain like BFR-id, 291 MT, BAR, IPA. 293 This document introduces new Sub-TLV under BIER Sub-TLV to advertise 294 the ethernet encapsulation capability and other associated parameters 295 of the encapsulation. 297 This Sub-TLV carries the information for the BIER Ethernet 298 encapsulation including the BitString length supported for a certain 299 pair. 301 It is advertised within the BIER Sub-TLV defined in [RFC8444] which 302 in-turn is carried within the OSPFv2 Extended Prefix TLV defined in 303 [RFC7684]. 305 This Sub-TLV MAY appear multiple times within a single BIER Sub-TLV. 306 If the same BitString length is repeated in multiple BIER Ethernet 307 encapsulation Sub-TLVs inside the same BIER Sub-TLV, the BIER Sub-TLV 308 MUST be ignored. 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 | Length | 314 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 315 | Max SI | BIFT-id | 316 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 317 |BS Len | Reserved | 318 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 320 Type: TBD2 (To be assigned by IANA). 322 Length: 8 324 Max SI: A 1 octet field encoding the Maximum Set Identifier 325 (Section 1 of [RFC8279]) used in the encapsulation for this BIER 326 subdomain for this BitString length. The first BIFT-id is for SI=0, 327 the second BIFT-id is for SI=1, etc. If the BIFT-id associated with 328 the Maximum Set Identifier exceeds the 20-bit range, the sub-sub-TLV 329 MUST be ignored. 331 BIFT-id: A 3-octet field, where the 20 rightmost bits represent the 332 first BIFT-id in the BIFT-id range. The 4 leftmost bits MUST be 333 ignored. 334 The "BIFT-id range" is the set of 20-bit values beginning with the 335 BIFT-id and ending with (BIFT-id + (Max SI)). These BIFT-id's are 336 used for BIER forwarding as described in [RFC8279] and [RFC8296]. 337 The size of the BIFT-id range is determined by the number of SI's 338 (Section 1 of [RFC8279]) that are used in the network. Each SI maps 339 to a single BIFT-id in the BIFT-id range: the first BIFT-id is for 340 SI=0, the second BIFT-id is for SI=1, etc. 341 If the BIFT-id associated with the Maximum Set Identifier exceeds 342 the 20-bit range, the BIER Ethernet Encapsulation Sub-sub-TLV 343 containing the error MUST be ignored. 344 BIFT-id ranges within all the BIER Ethernet Encapsulation sub-sub- 345 TLVs advertised by the same BFR MUST NOT overlap. If the overlap is 346 detected, the advertising router MUST be treated as if it did not 347 advertise any BIER Ethernet encapsulation sub-sub-TLVs. However the 348 BIFT-id ranges may overlap across different encapsulation types and 349 is allowed. As an example, the BIFT-id value in the Ethernet 350 encapsulation sub-sub-TLV may overlap with the Label value in the 351 Label range in BIER MPLS encapsulation sub-sub-TLV ([RFC8444] and is 352 allowed. 354 Local BitString Length (BS Len): A 4 bit field encoding the 355 bitstring length (as per [RFC8296]) supported for the encapsulation. 357 Reserved: SHOULD be set to 0 on transmission and MUST be ignored on 358 reception. 360 3.3. OSPFv3 BIER Ethernet Encapsulation Sub-TLV 362 BIER Sub-TLV defined in [I-D.ietf-bier-ospfv3-extensions] is used to 363 advertise the sub-domain id, and other associated parameters of the 364 sub-domain like BFR-id, MT, BAR, IPA. 366 This document introduces new Sub-TLV under BIER Sub-TLV to advertise 367 the ethernet encapsulation capability and other associated parameters 368 of the encapsulation. 370 This Sub-TLV carries the information for the BIER Ethernet 371 encapsulation including the BitString length supported for a certain 372 pair. 374 It is advertised within the BIER Sub-TLV defined in 375 [I-D.ietf-bier-non-mpls-bift-encoding] which in-turn is carried 376 within the Intra-Area-Prefix TLV or Inter-Area-Prefix TLV in OSPFv2 377 Extended LSA TLV defined in [RFC8362]. 379 This Sub-TLV MAY appear multiple times within a single BIER Sub-TLV. 380 If the same BitString length is repeated in multiple BIER Ethernet 381 encapsulation Sub-TLVs inside the same BIER Sub-TLV, the BIER Sub-TLV 382 MUST be ignored. 384 0 1 2 3 385 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 1 386 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 387 | Type | Length | 388 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 389 | Max SI | BIFT-id | 390 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 391 |BS Len | Reserved | 392 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 394 Type: TBD3 (To be assigned by IANA). 396 Length: 8 398 Max SI: A 1 octet field encoding the Maximum Set Identifier 399 (Section 1 of [RFC8279]) used in the encapsulation for this BIER 400 subdomain for this BitString length. The first BIFT-id is for SI=0, 401 the second BIFT-id is for SI=1, etc. If the BIFT-id associated with 402 the Maximum Set Identifier exceeds the 20-bit range, the sub-sub-TLV 403 MUST be ignored. 405 BIFT-id: A 3-octet field, where the 20 rightmost bits represent the 406 first BIFT-id in the BIFT-id range. The 4 leftmost bits MUST be 407 ignored. 408 The "BIFT-id range" is the set of 20-bit values beginning with the 409 BIFT-id and ending with (BIFT-id + (Max SI)). These BIFT-id's are 410 used for BIER forwarding as described in [RFC8279] and [RFC8296]. 411 The size of the BIFT-id range is determined by the number of SI's 412 (Section 1 of [RFC8279]) that are used in the network. Each SI maps 413 to a single BIFT-id in the BIFT-id range: the first BIFT-id is for 414 SI=0, the second BIFT-id is for SI=1, etc. 415 If the BIFT-id associated with the Maximum Set Identifier exceeds 416 the 20-bit range, the BIER Ethernet Encapsulation Sub-sub-TLV 417 containing the error MUST be ignored. 418 BIFT-id ranges within all the BIER Ethernet Encapsulation sub-sub- 420 TLVs advertised by the same BFR MUST NOT overlap. If the overlap is 421 detected, the advertising router MUST be treated as if it did not 422 advertise any BIER Ethernet encapsulation sub-sub-TLVs. However the 423 BIFT-id ranges may overlap across different encapsulation types and 424 is allowed. As an example, the BIFT-id value in the Ethernet 425 encapsulation sub-sub-TLV may overlap with the Label value in the 426 Label range in BIER MPLS encapsulation sub-sub-TLV 427 ([I-D.ietf-bier-non-mpls-bift-encoding] and is allowed. 429 Local BitString Length (BS Len): A 4 bit field encoding the 430 bitstring length (as per [RFC8296]) supported for the encapsulation. 432 Reserved: SHOULD be set to 0 on transmission and MUST be ignored on 433 reception. 435 4. Security Considerations 437 Security concerns for IS-IS are addressed in [RFC5304] and [RFC5310] 438 and the security concerns for IS-IS extensions for BIER are addressed 439 in [RFC8401]. This document introduces new sub-sub-TLV for the 440 already existing IS-IS TLVs defined for distributing the BIER sub- 441 domain information in [RFC8401]. It does not introduce any new 442 security risks to IS-IS. 444 Security concerns and required extensions for OSPFv2 are addressed in 445 [RFC2328] and [RFC7684] and the security concerns for OSPFv2 446 extensions for BIER are addressed in [RFC8444]. This document 447 introduces new Sub-TLV for the already existing OSPFv2 TLV defined 448 for distributing the BIER sub-domain information in [RFC8444]. It 449 does not introduce any new security risks to OSPFv2. 451 5. IANA Considerations 453 The document requests new allocations from the IANA registries as 454 follows 456 5.1. IS-IS sub-sub-TLVs for BIER Info sub-TLV Registry 458 BIER Ethernet Encapsulation sub-sub-TLV: TBD1 (suggested value 2) 460 5.2. OSPFv2 Extended Prefix TLV Sub-TLVs Registry 462 BIER Ethernet Encapsulation Sub-TLV: TBD2 (suggested value 11) 464 5.3. OSPFv3 Extended LSA Sub-TLVs Registry 466 BIER Ethernet Encapsulation Sub-TLV: TBD3 (suggested value 11) 468 6. Acknowledgments 470 The author wants to thank Antonie Przygienda for his comments and 471 suggestions. 473 7. References 475 7.1. Normative References 477 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 478 Requirement Levels", BCP 14, RFC 2119, 479 DOI 10.17487/RFC2119, March 1997, 480 . 482 [RFC8279] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A., 483 Przygienda, T., and S. Aldrin, "Multicast Using Bit Index 484 Explicit Replication (BIER)", RFC 8279, 485 DOI 10.17487/RFC8279, November 2017, 486 . 488 [RFC8296] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A., 489 Tantsura, J., Aldrin, S., and I. Meilik, "Encapsulation 490 for Bit Index Explicit Replication (BIER) in MPLS and Non- 491 MPLS Networks", RFC 8296, DOI 10.17487/RFC8296, January 492 2018, . 494 [RFC8401] Ginsberg, L., Ed., Przygienda, T., Aldrin, S., and Z. 495 Zhang, "Bit Index Explicit Replication (BIER) Support via 496 IS-IS", RFC 8401, DOI 10.17487/RFC8401, June 2018, 497 . 499 [RFC8444] Psenak, P., Ed., Kumar, N., Wijnands, IJ., Dolganow, A., 500 Przygienda, T., Zhang, J., and S. Aldrin, "OSPFv2 501 Extensions for Bit Index Explicit Replication (BIER)", 502 RFC 8444, DOI 10.17487/RFC8444, November 2018, 503 . 505 7.2. Informative References 507 [I-D.ietf-bier-non-mpls-bift-encoding] 508 Wijnands, I., Mishra, M., Xu, X., and H. Bidgoli, "An 509 Optional Encoding of the BIFT-id Field in the non-MPLS 510 BIER Encapsulation", Work in Progress, Internet-Draft, 511 draft-ietf-bier-non-mpls-bift-encoding-04, 30 May 2021, 512 . 515 [I-D.ietf-bier-ospfv3-extensions] 516 Psenak, P., Nainar, N. K., and I. Wijnands, "OSPFv3 517 Extensions for BIER", Work in Progress, Internet-Draft, 518 draft-ietf-bier-ospfv3-extensions-05, 19 November 2021, 519 . 522 [I-D.zzhang-bier-rift] 523 Zhang, Z., Ma, S., and Z. Zhang, "Supporting BIER with 524 RIFT", Work in Progress, Internet-Draft, draft-zzhang- 525 bier-rift-00, 5 March 2018, 526 . 529 [RFC1195] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and 530 dual environments", RFC 1195, DOI 10.17487/RFC1195, 531 December 1990, . 533 [RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, 534 DOI 10.17487/RFC2328, April 1998, 535 . 537 [RFC5120] Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi 538 Topology (MT) Routing in Intermediate System to 539 Intermediate Systems (IS-ISs)", RFC 5120, 540 DOI 10.17487/RFC5120, February 2008, 541 . 543 [RFC5304] Li, T. and R. Atkinson, "IS-IS Cryptographic 544 Authentication", RFC 5304, DOI 10.17487/RFC5304, October 545 2008, . 547 [RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic 548 Engineering", RFC 5305, DOI 10.17487/RFC5305, October 549 2008, . 551 [RFC5308] Hopps, C., "Routing IPv6 with IS-IS", RFC 5308, 552 DOI 10.17487/RFC5308, October 2008, 553 . 555 [RFC5310] Bhatia, M., Manral, V., Li, T., Atkinson, R., White, R., 556 and M. Fanto, "IS-IS Generic Cryptographic 557 Authentication", RFC 5310, DOI 10.17487/RFC5310, February 558 2009, . 560 [RFC7684] Psenak, P., Gredler, H., Shakir, R., Henderickx, W., 561 Tantsura, J., and A. Lindem, "OSPFv2 Prefix/Link Attribute 562 Advertisement", RFC 7684, DOI 10.17487/RFC7684, November 563 2015, . 565 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 566 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 567 May 2017, . 569 [RFC8362] Lindem, A., Roy, A., Goethals, D., Reddy Vallem, V., and 570 F. Baker, "OSPFv3 Link State Advertisement (LSA) 571 Extensibility", RFC 8362, DOI 10.17487/RFC8362, April 572 2018, . 574 Authors' Addresses 576 Senthil Dhanaraj (editor) 577 Huawei 578 Email: senthil.dhanaraj.ietf@gmail.com 580 Gang Yan (editor) 581 Huawei 582 Email: yangang@huawei.com 584 IJsbrand Wijnands 585 Cisco Systems, Inc. 586 Email: ice@cisco.com 588 Peter Psenak 589 Cisco Systems, Inc. 590 Email: ppsenak@cisco.com 592 Zhaohui Zhang 593 Juniper Networks. 594 Email: zzhang@juniper.net 596 Jingrong Xie 597 Huawei 598 Email: xiejingrong@huawei.com