idnits 2.17.1 draft-ietf-ospf-prefix-link-attr-11.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year == The document seems to contain a disclaimer for pre-RFC5378 work, but was first submitted on or after 10 November 2008. The disclaimer is usually necessary only for documents that revise or obsolete older RFCs, and that take significant amounts of text from those RFCs. If you can contact all authors of the source material and they are willing to grant the BCP78 rights to the IETF Trust, you can and should remove the disclaimer. Otherwise, the disclaimer is needed and you can ignore this comment. (See the Legal Provisions document at https://trustee.ietf.org/license-info for more information.) -- The document date (August 18, 2015) is 3173 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(See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Outdated reference: A later version (-18) exists of draft-ietf-bier-ospf-bier-extensions-00 == Outdated reference: A later version (-23) exists of draft-ietf-ospf-ospfv3-lsa-extend-06 == Outdated reference: A later version (-27) exists of draft-ietf-ospf-segment-routing-extensions-05 == Outdated reference: A later version (-04) exists of draft-francois-rtgwg-segment-routing-ti-lfa-00 Summary: 0 errors (**), 0 flaws (~~), 6 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group P. Psenak 3 Internet-Draft Cisco Systems 4 Intended status: Standards Track H. Gredler 5 Expires: February 19, 2016 Juniper Networks, Inc. 6 R. Shakir 7 Individual Contributor 8 W. Henderickx 9 Alcatel-Lucent 10 J. Tantsura 11 Ericsson 12 A. Lindem 13 Cisco Systems 14 August 18, 2015 16 OSPFv2 Prefix/Link Attribute Advertisement 17 draft-ietf-ospf-prefix-link-attr-11.txt 19 Abstract 21 OSPFv2 requires functional extension beyond what can readily be done 22 with the fixed-format Link State Advertisements (LSAs) as described 23 in RFC 2328. This document defines OSPF opaque LSAs based on Type- 24 Length-Value (TLV) tuples that can be used to associate additional 25 attributes with prefixes or links. Dependent on the application, 26 these prefixes and links may or not be advertised in the fixed-format 27 LSAs. The OSPF opaque LSAs are optional and fully backward 28 compatible. 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 February 19, 2016. 47 Copyright Notice 49 Copyright (c) 2015 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 This document may contain material from IETF Documents or IETF 63 Contributions published or made publicly available before November 64 10, 2008. The person(s) controlling the copyright in some of this 65 material may not have granted the IETF Trust the right to allow 66 modifications of such material outside the IETF Standards Process. 67 Without obtaining an adequate license from the person(s) controlling 68 the copyright in such materials, this document may not be modified 69 outside the IETF Standards Process, and derivative works of it may 70 not be created outside the IETF Standards Process, except to format 71 it for publication as an RFC or to translate it into languages other 72 than English. 74 Table of Contents 76 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 77 1.1. Requirements notation . . . . . . . . . . . . . . . . . . 3 78 2. OSPFv2 Extended Prefix Opaque LSA . . . . . . . . . . . . . . 3 79 2.1. OSPFv2 Extended Prefix TLV . . . . . . . . . . . . . . . 5 80 3. OSPFv2 Extended Link Opaque LSA . . . . . . . . . . . . . . . 8 81 3.1. OSPFv2 Extended Link TLV . . . . . . . . . . . . . . . . 9 82 4. Backward Compatibility . . . . . . . . . . . . . . . . . . . 10 83 5. Implementation Status . . . . . . . . . . . . . . . . . . . . 10 84 5.1. Implementation Survey Results . . . . . . . . . . . . . . 11 85 6. Security Considerations . . . . . . . . . . . . . . . . . . . 12 86 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 87 7.1. OSPF Extended Prefix Opaque LSA TLV Registry . . . . . . 13 88 7.2. OSPF Extended Prefix TLV Sub-TLV Registry . . . . . . . . 13 89 7.3. OSPF Extended Prefix TLV Flags Registry . . . . . . . . . 13 90 7.4. OSPF Extended Link Opaque LSA TLV Registry . . . . . . . 14 91 7.5. OSPF Extended Link TLV Sub-TLV Registry . . . . . . . . . 14 92 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 14 93 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 15 94 9.1. Normative References . . . . . . . . . . . . . . . . . . 15 95 9.2. Informative References . . . . . . . . . . . . . . . . . 15 96 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 98 1. Introduction 100 OSPFv2 requires functional extension beyond what can readily be done 101 with the fixed-format Link State Advertisements (LSAs) as described 102 in RFC 2328 [OSPFV2]. This document defines OSPF opaque LSAs based 103 on Type-Length-Value (TLV) tuples that can be used to associate 104 additional attributes with prefixes or links. Dependent on the 105 application, these prefixes and links may or not be advertised in the 106 fixed-format LSAs. The OSPF opaque LSAs are optional and fully 107 backward compatible. This is in contrast to the approach taken in 108 OSPFv3 [I-D.ietf-ospf-ospfv3-lsa-extend] where the existing LSAs will 109 be replaced by TLV-based extended LSAs. 111 New requirements such as source/destination routing, route tagging, 112 and segment routing necessitate this extension. 114 This specification defines the following OSPFv2 opaque LSAs: 116 1. OSPFv2 Extended Prefix Opaque LSA - Allows advertisement of 117 additional attributes for prefixes advertised in Router-LSAs, 118 Network-LSAs, Network-Summary-LSAs, NSSA-LSAs, and AS-External- 119 LSAs [OSPFV2] 121 2. OSPFv2 Extended Link Opaque LSA - Allows advertisement of 122 additional attributes for links advertised in Router-LSAs. 124 Additionally, the following TLVs are defined: 126 1. OSPFv2 Extended Prefix TLV - Top-level TLV advertising attributes 127 for a prefix in the OSPFv2 Extended Prefix Opaque LSA. 129 2. OSPFv2 Extended Link TLV - Top-level TLV advertising attributes 130 for a link in the OSPFv2 Extended Link Opaque LSA. 132 1.1. Requirements notation 134 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 135 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 136 document are to be interpreted as described in [RFC-KEYWORDS]. 138 2. OSPFv2 Extended Prefix Opaque LSA 140 The OSPFv2 Extended Prefix Opaque LSA will be used to advertise 141 additional prefix attributes. Opaque LSAs are described in [OPAQUE]. 143 Multiple OSPFv2 Extended Prefix Opaque LSAs can be advertised by an 144 OSPFv2 router. The flooding scope of the OSPFv2 Extended Prefix 145 Opaque LSA depends on the scope of the advertised prefixes and is 146 under the control of the advertising router. In some cases (e.g., 147 mapping server deployment [SEGMENT-ROUTING]), the LSA flooding scope 148 may be greater than the scope of the corresponding prefixes. 150 The format of the OSPFv2 Extended Prefix Opaque LSA is as follows: 152 0 1 2 3 153 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 1 154 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 155 | LS age | Options | 9, 10, or 11 | 156 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 157 | Opaque type | Opaque ID | 158 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 159 | Advertising Router | 160 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 161 | LS sequence number | 162 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 163 | LS checksum | Length | 164 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 165 | | 166 +- TLVs -+ 167 | ... | 169 OSPFv2 Extended Prefix Opaque LSA 171 The opaque type used by OSPFv2 Extended Prefix Opaque LSA is 7. The 172 opaque type is used to differentiate the various type of OSPFv2 173 Opaque LSA and is described in section 3 of [OPAQUE]. The LSA 174 "Length" field [OSPFV2] represents the total length (in octets) of 175 the Opaque LSA including the LSA header and all TLVs (including 176 padding). 178 The Opaque ID field is an arbitrary value used to maintain multiple 179 Extended Prefix Opaque LSAs. For OSPFv2 Extended Prefix Opaque LSAs, 180 the Opaque ID has no semantic significance other than to 181 differentiate Extended Prefix Opaque LSAs originated by the same 182 OSPFv2 router. If multiple Extended Prefix Opaque LSAs include the 183 same prefix, the attributes from the Opaque LSA with the lowest 184 Opaque ID SHOULD be used. 186 The format of the TLVs within the body of the OSPFv2 Extended Prefix 187 Opaque LSA is the same as the format used by the Traffic Engineering 188 Extensions to OSPF [TE]. The variable TLV section consists of one or 189 more nested Type/Length/Value (TLV) tuples. Nested TLVs are also 190 referred to as sub-TLVs. The format of each TLV is: 192 0 1 2 3 193 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 1 194 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 195 | Type | Length | 196 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 197 | Value | 198 o 199 o 200 o 201 | | 202 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 204 TLV Format 206 The Length field defines the length of the value portion in octets 207 (thus a TLV with no value portion would have a length of 0). The TLV 208 is padded to 4-octet alignment; padding is not included in the length 209 field (so a 3-octet value would have a length of 3, but the total 210 size of the TLV would be 8 octets). Nested TLVs are also 32-bit 211 aligned. For example, a 1-byte value would have the length field set 212 to 1, and 3 octets of padding would be added to the end of the value 213 portion of the TLV. 215 2.1. OSPFv2 Extended Prefix TLV 217 The OSPF Extended Prefix TLV is used to advertise additional 218 attributes associated with the prefix. Multiple OSPF Extended Prefix 219 TLVs MAY be advertised in each OSPFv2 Extended Prefix Opaque LSA. 220 However, since the opaque LSA type defines the flooding scope, the 221 LSA flooding scope MUST satisfy the application specific requirements 222 for all the prefixes included in a single OSPFv2 Extended Prefix 223 Opaque LSA. The OSPF Extended Prefix TLV has the following format: 225 0 1 2 3 226 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 1 227 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 228 | Type | Length | 229 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 230 | Route Type | Prefix Length | AF | Flags | 231 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 232 | Address Prefix (variable) | 233 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 234 | Sub-TLVs (variable) | 235 +- -+ 236 | | 238 OSPFv2 Extended Prefix TLV 240 Type 241 The TLV type. The value is 1 for this TLV type. 243 Length 244 Variable dependent on sub-TLVs. 246 Route Type 247 Route type: type of the OSPF route. If the route type is 0 248 (Unspecified), the information inside the OSPF External Prefix TLV 249 applies to the prefix regardless of prefix's route-type. This is 250 useful when prefix specific attributes are advertised by an 251 external entity that is not aware of the route-type associated 252 with the prefix. Supported types are: 254 0 - Unspecified 256 1 - Intra-Area 258 3 - Inter-Area 260 5 - AS External 262 7 - NSSA External 264 These route types correspond directly to the OSPFv2 LSAs types as 265 defined in http://www.iana.org/assignments/ospfv2-parameters/ 266 ospfv2-parameters.xhtml#ospfv2-parameters-5. Specification of 267 route types other than those defined will prevent correlation with 268 existing OSPFv2 LSAs and is beyond the scope this specification. 270 Prefix Length 271 Length in the prefix in bits. 273 AF 274 Address family for the prefix. Currently, the only supported 275 value is 0 for IPv4 unicast. The inclusion of address family in 276 this TLV allows for future extension. 278 Flags 279 This one octet field contains flags applicable to the prefix. 280 Supported Flags include: 282 0x80 - A-Flag (Attach flag): An Area Border Router (ABR) 283 generating an Extended Prefix TLV for inter-area prefix that is 284 locally connected or attached in other connected area SHOULD 285 set this flag. 287 0x40 - N-Flag (Node Flag): Set when the prefix identifies the 288 advertising router i.e., the prefix is a host prefix 289 advertising a globally reachable address typically associated 290 with a loopback address. The advertising router MAY choose to 291 not set this flag even when the above conditions are met. If 292 the flag is set and the prefix length is not a host prefix then 293 the flag MUST be ignored. The flag is preserved when the 294 OSPFv2 Extended Prefix Opaque LSA is propagated between areas. 296 Address Prefix 297 For the address family IPv4 unicast, the prefix itself encoded as 298 a 32-bit value. The default route is represented by a prefix of 299 length 0. Prefix encoding for other address families is beyond 300 the scope of this specification. 302 If this TLV is advertised multiple times for the same prefix in the 303 same OSPFv2 Extended Prefix Opaque LSA, only the first instance of 304 the TLV is used by receiving OSPFv2 Routers. This situation SHOULD 305 be logged as an error. 307 If this TLV is advertised multiple times for the same prefix in 308 different OSPFv2 Extended Prefix Opaque LSAs originated by the same 309 OSPF router, the OSPF advertising router is re-originating Extended 310 Prefix Opaque LSAs for multiple prefixes and is most likely repacking 311 Extended-Prefix-TLVs in Extended Prefix Opaque LSAs. In this case, 312 the Extended-Prefix-TLV in the Extended Prefix Opaque LSA with the 313 smallest Opaque ID is used by receiving OSPFv2 Routers. This 314 situation may be logged as a warning. 316 It is RECOMMENDED that OSPF routers advertising Extended Prefix TLVs 317 in different Extended Prefix Opaque LSAs re-originate these LSAs in 318 ascending order of Opaque ID to minimize the disruption. 320 If this TLV is advertised multiple times for the same prefix in 321 different OSPFv2 Extended Prefix Opaque LSAs originated by different 322 OSPF routers, the application using the information is required to 323 determine which OSPFv2 Extended Prefix Opaque LSA is used. For 324 example, the application could prefer the LSA providing the best path 325 to the prefix. 327 This document creates a registry for OSPF Extended Prefix sub-TLVs in 328 Section 7. 330 3. OSPFv2 Extended Link Opaque LSA 332 The OSPFv2 Extended Link Opaque LSA will be used to advertise 333 additional link attributes. Opaque LSAs are described in [OPAQUE]. 335 The OSPFv2 Extended Link Opaque LSA has an area flooding scope. 336 Multiple OSPFv2 Extended Link Opaque LSAs can be advertised by a 337 single router in an area. 339 The format of the OSPFv2 Extended Link Opaque LSA is as follows: 341 0 1 2 3 342 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 1 343 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 344 | LS age | Options | 10 | 345 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 346 | Opaque type | Opaque ID | 347 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 348 | Advertising Router | 349 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 350 | LS sequence number | 351 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 352 | LS checksum | Length | 353 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 354 | | 355 +- TLVs -+ 356 | ... | 358 OSPFv2 Extended Link Opaque LSA 360 The Opaque type used by OSPFv2 Extended Link Opaque LSA is 8. The 361 opaque type is used to differentiate the various type of OSPFv2 362 Opaque LSA and is described in section 3 of [OPAQUE]. The LSA 363 "Length" field [OSPFV2] represents the total length (in octets) of 364 the Opaque LSA including the LSA header and all TLVs (including 365 padding). 367 The Opaque ID field is an arbitrary value used to maintain multiple 368 Extended Prefix Opaque LSAs. For OSPFv2 Extended Link Opaque LSAs, 369 the Opaque ID has no semantic significance other than to 370 differentiate Extended Link Opaque LSAs originated by the same OSPFv2 371 router. If multiple Extended Link Opaque LSAs include the same link, 372 the attributes from the Opaque LSA with the lowest Opaque ID will be 373 used. 375 The format of the TLVs within the body of the OSPFv2 Extended Link 376 Opaque LSA is the same as described in Section 2. 378 3.1. OSPFv2 Extended Link TLV 380 The OSPFv2 Extended Link TLV is used to advertise various attributes 381 of the link. It describes a single link and is constructed of a set 382 of Sub-TLVs. There are no ordering requirements for the Sub-TLVs. 383 Only one Extended Link TLV SHALL be advertised in each Extended Link 384 Opaque LSA, allowing for fine granularity changes in the topology. 386 The Extended Link TLV has following format: 388 0 1 2 3 389 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 1 390 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 391 | Type | Length | 392 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 393 | Link-Type | Reserved | 394 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 395 | Link ID | 396 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 397 | Link Data | 398 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 399 | Sub-TLVs (variable) | 400 +- -+ 401 | | 403 OSPFv2 Extended Link TLV 405 Type 406 The TLV type. The value is 1 for this TLV type. 408 Length 409 Variable dependent on sub-TLVs. 411 Link-Type 412 Link-Type is defined in section A.4.2 of [OSPFV2] and 413 http://www.iana.org/assignments/ospfv2-parameters/ 414 ospfv2-parameters.xhtml#ospfv2-parameters-6. Specification of 415 link types other than those defined will prevent correlation with 416 existing OSPFv2 Router-LSA links and is beyond the scope this 417 specification. 419 Link-ID 420 Link-ID is defined in section A.4.2 of [OSPFV2]. 422 Link Data 423 Link-Data is defined in section A.4.2 of [OSPFV2]. 425 If this TLV is advertised multiple times in the same OSPFv2 Extended 426 Link Opaque LSA, only the first instance of the TLV is used by 427 receiving OSPFv2 Routers. This situation SHOULD be logged as an 428 error. 430 If this TLV is advertised multiple times for the same link in 431 different OSPFv2 Extended Link Opaque LSAs originated by the same 432 OSPF router, the Extended Link TLV in the Extended Link Opaque LSA 433 with the smallest Opaque ID is used by receiving OSPFv2 Routers. 434 This situation may be logged as a warning. 436 It is RECOMMENDED that OSPF routers advertising Extended Link TLVs in 437 different Extended Link Opaque LSAs re-originate these LSAs in 438 ascending order of Opaque ID to minimize the disruption. 440 This document creates a registry for OSPF Extended Link sub-TLVs in 441 Section 7. 443 4. Backward Compatibility 445 Since opaque OSPFv2 LSAs are optional and backward compatible 446 [OPAQUE], the extensions described herein are fully backward 447 compatible. However, future OSPFv2 applications utilizing these 448 extensions MUST address backward compatibility of the corresponding 449 functionality. 451 5. Implementation Status 453 Note to RFC Editor: this section may be removed on publication as an 454 RFC. 456 This section records the status of known implementations of the 457 protocol defined by this specification at the time of posting of this 458 Internet-Draft, and is based on a proposal described in RFC 6982. 459 The description of implementations in this section is intended to 460 assist the IETF in its decision processes in progressing drafts to 461 RFCs. Please note that the listing of any individual implementation 462 here does not imply endorsement by the IETF. Furthermore, no effort 463 has been spent to verify the information presented here that was 464 supplied by IETF contributors. This is not intended as, and must not 465 be construed to be, a catalog of available implementations or their 466 features. Readers are advised to note that other implementations may 467 exist. 469 According to RFC 6982, "this will allow reviewers and working groups 470 to assign due consideration to documents that have the benefit of 471 running code, which may serve as evidence of valuable experimentation 472 and feedback that have made the implemented protocols more mature. 473 It is up to the individual working groups to use this information as 474 they see fit". 476 5.1. Implementation Survey Results 478 An implementation survey with seven questions related to the 479 implementer's support of OSPFv2 Prefix/Link Attributes was sent to 480 the OSPF WG list and several known implementers. This section 481 contains responses from four implementers who completed the survey. 482 No external means were used to verify the accuracy of the information 483 submitted by the respondents. The respondents are considered experts 484 on the products they reported on. Additionally, responses were 485 omitted from implementers who indicated that they have not 486 implemented the function yet. 488 Four vendors and one open source entity replied to the survey. These 489 included Alcatel-Lucent, Cisco, Huawei, Juniper, and FreeRouter 490 (http://freerouter.nop.hu). Cisco and Alcatel-Lucent also did 491 interoperability testing. FreeRouter did interoperability testing 492 with Cisco. The Cisco, Alcatel-Lucent, and FreeRouter 493 implementations are in released software versions. The Huawei and 494 Juniper implementation software releases are pending. For prefix 495 attributes, the recent change incorporating the A-Flag is pending 496 implementation for all four vendors. The FreeRouter implementation 497 includes support for the A-Flag. Implementation of the N-flag is 498 pending for the Huawei and Juniper implementations. Otherwise, all 499 the survey respondents have full implementations. For all four 500 vendors and the FreeRouter implementation, segment routing 501 [SEGMENT-ROUTING] was an application making use of the extensions. 502 Additionally, Cisco has implemented Topology-Independent Loop-Free 503 Alternatives (TI-LFA) [TI-LFA] and Bit Indexed Egress Replication 504 (BIER) advertisement [BIER]. 506 Alcatel-Lucent's support of this specification is included in SR OS, 507 Release 13.0.R4. Cisco's support is included in IOS-XR 5.3.2. The 508 FreeRouter implementation is available in the FreeRouter 15.6.4 509 distribution. Huawei and Juniper will respectively provide support 510 in future versions Versatile Routing Platform (VRP) and JUniper 511 Network Operating System (JUNOS). 513 6. Security Considerations 515 In general, new LSAs defined in this document are subject to the same 516 security concerns as those described in [OSPFV2] and [OPAQUE]. 518 OSPFv2 applications utilizing these OSPFv2 extensions must define the 519 security considerations relating to those applications in the 520 specifications corresponding to those applications. 522 Additionally, implementations must assure that malformed TLV and Sub- 523 TLV permutations are detected and do not provide a vulnerability for 524 attackers to crash the OSPFv2 router or routing process. Malformed 525 LSAs MUST NOT be stored in the Link State Database (LSDB), 526 acknowledged, or reflooded. Reception of malformed LSAs SHOULD be 527 counted and/or logged for further analysis. 529 7. IANA Considerations 531 This specification updates the Opaque Link-State Advertisements (LSA) 532 Option Types with the following values: 534 o 7 (IANA Early Allocation [RFC7120]) - OSPFv2 Extended Prefix 535 Opaque LSA 537 o 8 (IANA Early Allocation [RFC7120]) - OSPFv2 Extended Link Opaque 538 LSA 540 This specification also creates five new registries: 542 o OSPF Extended Prefix Opaque LSA TLVs 544 o OSPF Extended Prefix TLV Sub-TLVs 546 o OSPF Extended Prefix TLV Flags 548 o OSPF Extended Link Opaque LSA TLVs 550 o OSPF Extended Link TLV Sub-TLVs 552 7.1. OSPF Extended Prefix Opaque LSA TLV Registry 554 The "OSPF Extend Prefix Opaque LSA TLV" registry will define top- 555 level TLVs for the Extended Prefix Opaque LSAs and should be added to 556 the "Open Shortest Path First v2 (OSPFv2) Parameters" registries 557 group. New values can be allocated via IETF Review or IESG Approval. 559 The following initial values are allocated: 561 o 0 - Reserved 563 o 1 - OSPF Extended Prefix TLV 565 Types in the range 32768-33023 are for experimental use; these will 566 not be registered with IANA, and MUST NOT be mentioned by RFCs. 568 Types in the range 33024-65535 are not to be assigned at this time. 569 Before any assignments can be made in the 33024-65535 range, there 570 MUST be an IETF specification that specifies IANA Considerations that 571 covers the range being assigned. 573 7.2. OSPF Extended Prefix TLV Sub-TLV Registry 575 The "OSPF Extended Prefix TLV sub-TLV" registry will define sub-TLVs 576 at any level of nesting for Extended Prefix TLVs and should be added 577 to the "Open Shortest Path First v2 (OSPFv2) Parameters" registries 578 group. New values can be allocated via IETF Review or IESG Approval. 580 The following initial values are allocated: 582 o 0 - Reserved 584 Types in the range 32768-33023 are for experimental use; these will 585 not be registered with IANA, and MUST NOT be mentioned by RFCs. 587 Types in the range 33024-65535 are not to be assigned at this time. 588 Before any assignments can be made in the 33024-65535 range, there 589 MUST be an IETF specification that specifies IANA Considerations that 590 covers the range being assigned. 592 7.3. OSPF Extended Prefix TLV Flags Registry 594 The "OSPF Extended Prefix TLV Flags" registry will define the bits in 595 the 8-bit Extended Prefix TLV Flags (Section 2.1). This 596 specification defines the N (0x80) and A (0x40) bits. The registry 597 should be added to the "Open Shortest Path First v2 (OSPFv2) 598 Parameters" registries group. New values can be allocated via IETF 599 Review or IESG Approval. 601 7.4. OSPF Extended Link Opaque LSA TLV Registry 603 The "OSPF Extended Link Opaque LSA TLV" registry will define top- 604 level TLVs for Extended Link Opaque LSAs and should be added to the 605 "Open Shortest Path First v2 (OSPFv2) Parameters" registries group. 606 New values can be allocated via IETF Review or IESG Approval. 608 Following initial values are allocated: 610 o 0 - Reserved 612 o 1 - OSPFv2 Extended Link TLV 614 Types in the range 32768-33023 are for experimental use; these will 615 not be registered with IANA, and MUST NOT be mentioned by RFCs. 617 Types in the range 33024-65535 are not to be assigned at this time. 618 Before any assignments can be made in the 33024-65535 range, there 619 MUST be am IETF specification that specifies IANA Considerations that 620 covers the range being assigned. 622 7.5. OSPF Extended Link TLV Sub-TLV Registry 624 The OSPF Extended Link TLV sub-TLV registry will define sub-TLVs at 625 any level of nesting for Extended Link TLVs and should be added to 626 the "Open Shortest Path First v2 (OSPFv2) Parameters" registries 627 group. New values can be allocated via IETF Review or IESG Approval. 629 The following initial values are allocated: 631 o 0 - Reserved 633 Types in the range 32768-33023 are for experimental use; these will 634 not be registered with IANA, and MUST NOT be mentioned by RFCs. 635 Types in the range 33024-65535 are not to be assigned at this time. 636 Before any assignments can be made in the 33024-65535 range, there 637 MUST be an IETF specification that specifies IANA Considerations that 638 covers the range being assigned. 640 8. Acknowledgments 642 We would like to thank Anton Smirnov for his contribution. 644 Thanks to Tony Przygienda for his review and comments. 646 Thanks to Wim Henderickx, Greg Harkins, Peter Psenak, Eric Wu, 647 Shraddha Hegde, and Csaba Mate for their responses to the 648 implementation survey. 650 Thanks to Tom Petch for review and comments. 652 Thanks to Alia Atlas and Alvaro Retana for AD review and comments. 654 Thanks to Carlos Pignataro and Ron Bonica for Operations Directorate 655 review and comments. 657 Thanks to Suresh Krishnan for Gen-ART review and comments. 659 Thanks to Ben Campbell, Kathleen Moriarty, and Barry Leiba for IESG 660 review and comments. 662 9. References 664 9.1. Normative References 666 [OPAQUE] Berger, L., Bryskin, I., Zinin, A., and R. Coltun, "The 667 OSPF Opaque LSA Option", RFC 5250, July 2008. 669 [OSPFV2] Moy, J., "OSPF Version 2", RFC 2328, April 1998. 671 [RFC-KEYWORDS] 672 Bradner, S., "Key words for use in RFCs to Indicate 673 Requirement Levels", RFC 2119, March 1997. 675 [TE] Katz, D., Yeung, D., and K. Kompella, "Traffic Engineering 676 Extensions to OSPF", RFC 3630, September 2003. 678 9.2. Informative References 680 [BIER] Psenak, P., Kumar, N., Wijnands, I., Dolganow, A., 681 Przygienda, T., Zhang, J., and S. Aldrin, "OSPF Extensions 682 for BIER", draft-ietf-bier-ospf-bier-extensions-00.txt 683 (work in progress), April 2015. 685 [I-D.ietf-ospf-ospfv3-lsa-extend] 686 Lindem, A., Mirtorabi, S., Roy, A., and F. Baker, "OSPFv3 687 LSA Extendibility", draft-ietf-ospf-ospfv3-lsa-extend-06 688 (work in progress), February 2015. 690 [RFC7120] Cotton, M., "Early IANA Allocation of Standards Track Code 691 Points", BCP 100, RFC 7120, January 2014. 693 [SEGMENT-ROUTING] 694 Psenak, P., Previdi, S., Filsfils, C., Gredler, H., 695 Shakir, R., Henderickx, W., and J. Tantsura, "OSPF 696 Extensions for Segment Routing", draft-ietf-ospf-segment- 697 routing-extensions-05.txt (work in progress), June 2015. 699 [TI-LFA] Francois, P., Filsfils, C., Bashandy, A., Decraene, B., 700 and S. Litkowski, "Topology Independent Fast Reroute using 701 Segment Routing", draft-francois-rtgwg-segment-routing-ti- 702 lfa-00.txt (work in progress), August 2014. 704 Authors' Addresses 706 Peter Psenak 707 Cisco Systems 708 Apollo Business Center 709 Mlynske nivy 43 710 Bratislava, 821 09 711 Slovakia 713 Email: ppsenak@cisco.com 715 Hannes Gredler 716 Juniper Networks, Inc. 717 1194 N. Mathilda Ave. 718 Sunnyvale, CA 94089 719 USA 721 Email: hannes@juniper.net 723 Rob Shakir 724 Individual Contributor 725 London 726 UK 728 Email: rjs@rob.sh 730 Wim Henderickx 731 Alcatel-Lucent 732 Copernicuslaan 733 Antwerp, 2018 94089 734 Belgium 736 Email: wim.henderickx@alcatel-lucent.com 737 Jeff Tantsura 738 Ericsson 739 300 Holger Way 740 San Jose, CA 95134 741 USA 743 Email: jeff.tantsura@ericsson.com 745 Acee Lindem 746 Cisco Systems 747 301 Midenhall Way 748 Cary, NC 27513 749 USA 751 Email: acee@cisco.com