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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group K. Kompella (Editor) 3 Internet Draft Y. Rekhter (Editor) 4 Category: Standards Track Juniper Networks 5 Expires: February 2003 August 2002 7 OSPF Extensions in Support of Generalized MPLS 9 draft-ietf-ccamp-ospf-gmpls-extensions-08.txt 11 Status of this Memo 13 This document is an Internet-Draft and is in full conformance with 14 all provisions of Section 10 of RFC2026. 16 Internet-Drafts are working documents of the Internet Engineering 17 Task Force (IETF), its areas, and its working groups. Note that 18 other groups may also distribute working documents as Internet- 19 Drafts. 21 Internet-Drafts are draft documents valid for a maximum of six months 22 and may be updated, replaced, or obsoleted by other documents at any 23 time. It is inappropriate to use Internet-Drafts as reference 24 material or to cite them other than as ``work in progress.'' 26 The list of current Internet-Drafts can be accessed at 27 http://www.ietf.org/ietf/1id-abstracts.txt 29 The list of Internet-Draft Shadow Directories can be accessed at 30 http://www.ietf.org/shadow.html. 32 Copyright Notice 34 Copyright (C) The Internet Society (2002). All Rights Reserved. 36 Abstract 38 This document specifies encoding of extensions to the OSPF routing 39 protocol in support of Generalized Multi-Protocol Label Switching. 41 Summary for Sub-IP Area 43 (This section to be removed before publication.) 45 0.1. Summary 47 This document specifies encoding of extensions to the OSPF routing 48 protocol in support of Generalized Multi-Protocol Label Switching 49 (GMPLS). The description of the extensions is specified in [GMPLS- 50 ROUTING]. 52 0.2. Where does it fit in the Picture of the Sub-IP Work 54 This work fits squarely in either the CCAMP or OSPF box. 56 0.3. Why is it Targeted at this WG 58 This draft is targeted at the CCAMP or the OSPF WG, because this 59 draft specifies the extensions to the OSPF routing protocols in 60 support of GMPLS, because GMPLS is within the scope of the CCAMP WG, 61 and because OSPF is within the scope of the OSPF WG. 63 0.4. Justification 65 The WG should consider this document as it specifies the extensions 66 to the OSPF routing protocols in support of GMPLS. 68 1. Specification of Requirements 70 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 71 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 72 document are to be interpreted as described in RFC 2119 [RFC2119]. 74 2. Introduction 76 This document specifies extensions to the OSPF routing protocol in 77 support of carrying link state information for Generalized Multi- 78 Protocol Label Switching (GMPLS). The set of required enhancements to 79 OSPF are outlined in [GMPLS-ROUTING]. 81 3. OSPF Routing Enhancements 83 In this section we define the enhancements to the TE properties of 84 GMPLS TE links that can be announced in OSPF TE LSAs. The Traffic 85 Engineering (TE) LSA, which is an opaque LSA with area flooding scope 86 [OSPF-TE], has only one top-level Type/Length/Value (TLV) triplet and 87 has one or more nested sub-TLVs for extensibility. The top-level TLV 88 can take one of two values (1) Router Address or (2) Link. In this 89 document, we enhance the sub-TLVs for the Link TLV in support of 90 GMPLS. Specifically, we add the following sub-TLVs to the Link TLV: 92 Sub-TLV Type Length Name 93 11 8 Link Local/Remote Identifiers 94 14 4 Link Protection Type 95 15 variable Interface Switching Capability Descriptor 96 16 variable Shared Risk Link Group 98 3.1. Link Local/Remote Identifiers 100 A Link Local/Remote Identifiers is a sub-TLV of the Link TLV. The 101 type of this sub-TLV is 11, and length is eight octets. The value 102 field of this sub-TLV contains four octets of Link Local Identifier 103 followed by four octets of Link Remote Idenfier (see Section "Support 104 for unnumbered links" of [GMPLS-ROUTING]). If the Link Remote 105 Identifier is unknown, it is set to 0. 107 0 1 2 3 108 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 1 109 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 110 | Link Local Idenfiier | 111 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 112 | Link Remote Idenfiier | 113 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 115 A node can communicate its Link Local Identifier to its neighbor 116 using a link local Opaque LSA, as described in Section "Exchanging 117 Link Local TE Information". 119 3.2. Link Protection Type 121 The Link Protection Type is a sub-TLV of the Link TLV. The type of 122 this sub-TLV is 14, and length is four octets. 124 0 1 2 3 125 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 1 126 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 127 |Protection Cap | Reserved | 128 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 130 The first octet is a bit vector describing the protection 131 capabilities of the link (see Section "Link Protection Type" of 132 [GMPLS-ROUTING]). They are: 134 0x01 Extra Traffic 136 0x02 Unprotected 138 0x04 Shared 140 0x08 Dedicated 1:1 142 0x10 Dedicated 1+1 144 0x20 Enhanced 146 0x40 Reserved 148 0x80 Reserved 150 The remaining three octets SHOULD be set to zero by the sender, and 151 SHOULD be ignored by the receiver. 153 The Link Protection Type sub-TLV may occur at most once within the 154 Link TLV. 156 3.3. Shared Risk Link Group (SRLG) 158 The SRLG is a sub-TLV (of type 16) of the Link TLV. The length is the 159 length of the list in octets. The value is an unordered list of 32 160 bit numbers that are the SRLGs that the link belongs to. The format 161 of the value field is as shown below: 163 0 1 2 3 164 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 1 165 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 166 | Shared Risk Link Group Value | 167 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 168 | ............ | 169 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 170 | Shared Risk Link Group Value | 171 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 173 This sub-TLV carries the Shared Risk Link Group information (see 174 Section "Shared Risk Link Group Information" of [GMPLS-ROUTING]). 176 The SRLG sub-TLV may occur at most once within the Link TLV. 178 3.4. Interface Switching Capability Descriptor 180 The Interface Switching Capability Descriptor is a sub-TLV (of type 181 15) of the Link TLV. The length is the length of value field in 182 octets. The format of the value field is as shown below: 184 0 1 2 3 185 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 1 186 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 187 | Switching Cap | Encoding | Reserved | 188 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 189 | Max LSP Bandwidth at priority 0 | 190 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 191 | Max LSP Bandwidth at priority 1 | 192 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 193 | Max LSP Bandwidth at priority 2 | 194 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 195 | Max LSP Bandwidth at priority 3 | 196 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 197 | Max LSP Bandwidth at priority 4 | 198 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 199 | Max LSP Bandwidth at priority 5 | 200 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 201 | Max LSP Bandwidth at priority 6 | 202 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 203 | Max LSP Bandwidth at priority 7 | 204 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 205 | Switching Capability-specific information | 206 | (variable) | 207 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 209 The Switching Capability (Switching Cap) field contains one of the 210 following values: 212 1 Packet-Switch Capable-1 (PSC-1) 213 2 Packet-Switch Capable-2 (PSC-2) 214 3 Packet-Switch Capable-3 (PSC-3) 215 4 Packet-Switch Capable-4 (PSC-4) 216 51 Layer-2 Switch Capable (L2SC) 217 100 Time-Division-Multiplex Capable (TDM) 218 150 Lambda-Switch Capable (LSC) 219 200 Fiber-Switch Capable (FSC) 221 The Encoding field contains one of the values specified in Section 222 3.1.1 of [GMPLS-SIG]. 224 Maximum LSP Bandwidth is encoded as a list of eight 4 octet fields in 225 the IEEE floating point format, with priority 0 first and priority 7 226 last. The units are bytes (not bits!) per second. 228 The content of the Switching Capability specific information field 229 depends on the value of the Switching Capability field. 231 When the Switching Capability field is PSC-1, PSC-2, PSC-3, or PSC-4, 232 the Switching Capability specific information field includes Minimum 233 LSP Bandwidth, Interface MTU, and padding. 235 0 1 2 3 236 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 1 237 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 238 | Minimum LSP Bandwidth | 239 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 240 | Interface MTU | Padding | 241 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 243 The Minimum LSP Bandwidth is is encoded in a 4 octets field in the 244 IEEE floating point format. The units are bytes (not bits!) per 245 second. The Interface MTU is encoded as a 2 octets integer. The 246 padding is 2 octets, and is used to make the Interface Switching 247 Capability Descriptor sub-TLV 32-bits aligned. It SHOULD be set to 248 zero by the sender and SHOULD be ignored by the receiver. 250 When the Switching Capability field is L2SC, there is no Switching 251 Capability specific information field present. 253 When the Switching Capability field is TDM, the Switching Capability 254 specific information field includes Minimum LSP Bandwidth, an 255 indication whether the interface supports Standard or Arbitrary 256 SONET/SDH, and padding. 258 0 1 2 3 259 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 1 260 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 261 | Minimum LSP Bandwidth | 262 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 263 | Indication | Padding | 264 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 266 The Minimum LSP Bandwidth is encoded in a 4 octets field in the IEEE 267 floating point format. The units are bytes (not bits!) per second. 268 The indication whether the interface supports Standard or Arbitrary 269 SONET/SDH is encoded as 1 octet. The value of this octet is 0 if the 270 interface supports Standard SONET/SDH, and 1 if the interface 271 supports Arbitrary SONET/SDH. The padding is 3 octets, and is used 272 to make the Interface Switching Capability Descriptor sub-TLV 32-bits 273 aligned. It SHOULD be set to zero by the sender and SHOULD be ignored 274 by the receiver. 276 When the Switching Capability field is LSC, there is no Switching 277 Capability specific information field present. 279 To support interfaces that have more than one Interface Switching 280 Capability Descriptor (see Section "Interface Switching Capability 281 Descriptor" of [GMPLS-ROUTING]) the Interface Switching Capability 282 Descriptor sub-TLV may occur more than once within the Link TLV. 284 4. Implications on Graceful Restart 286 The restarting node should follow the OSPF restart procedures [OSPF- 287 RESTART], and the RSVP-TE restart procedures [GMPLS-RSVP]. 289 When a restarting node is going to originate its TE LSAs, the TE LSAs 290 containing Link TLV should be originated with 0 unreserved bandwidth, 291 Traffic Engineering metric set to 0xffffffff, and if the Link has LSC 292 or FSC as its Switching Capability then also with 0 as Max LSP 293 Bandwidth, until the node is able to determine the amount of 294 unreserved resources taking into account the resources reserved by 295 the already established LSPs that have been preserved across the 296 restart. Once the restarting node determines the amount of unreserved 297 resources, taking into account the resources reserved by the already 298 established LSPs that have been preserved across the restart, the 299 node should advertise these resources in its TE LSAs. 301 In addition in the case of a planned restart prior to restarting, the 302 restarting node SHOULD originate the TE LSAs containing Link TLV with 303 0 as unreserved bandwidth, and if the Link has LSC or FSC as its 304 Switching Capability then also with 0 as Max LSP Bandwidth. This 305 would discourage new LSP establishment through the restarting router. 307 Neighbors of the restarting node should continue advertise the actual 308 unreserved bandwidth on the TE links from the neighbors to that node. 310 Regular graceful restart should not be aborted if a TE LSA or TE 311 topology changes. TE graceful restart need not be aborted if a TE LSA 312 or TE topology changes. 314 5. Exchanging Link Local TE Information 316 It is often useful for a node to communicate some Traffic Engineering 317 information for a given interface to its neighbors on that interface. 318 One example of this is a Link Local Identifier. If nodes X and Y are 319 connected by an unnumbered point-to-point interface I, then X's Link 320 Local Identifier for I is Y's Link Remote Identifier for I. X can 321 communicate its Link Local Identifer for I by exchanging with Y a TE 322 link local opaque LSA described below. Note that this information 323 need only be exchanged over interface I, hence the use of a link 324 local Opaque LSA. 326 A TE Link Local LSA is an opaque LSA of type 9 (link-local flooding 327 scope) with Opaque Type [TBD] and Opaque ID of 0. 329 0 1 2 3 330 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 1 331 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 332 | LS age | Options | 9 | 333 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 334 | Opaque Type | Opaque ID | 335 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 336 | Advertising Router | 337 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 338 | LS sequence number | 339 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 340 | LS checksum | length | 341 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 342 | | 343 +- TLVs -+ 344 | ... | 346 The format of the TLVs that make up the body of the TE Link Local LSA 347 is the same as that of the TE TLVs: a 2-octet Type field followed by 348 a 2-octet Length field which indicates the length of the Value field 349 in octets. The Value field is zero-padded at the end to a four octet 350 boundary. 352 The only TLV defined here is the Link Local Identifier TLV, with Type 353 1, Length 4 and Value the 32 bit Link Local Identifier for the link 354 over which the TE Link Local LSA is exchanged. 356 6. Normative References 358 [OSPF-TE] Katz, D., Yeung, D. and Kompella, K., "Traffic Engineering 359 Extensions to OSPF", (work in progress) 361 [GMPLS-SIG] Berger, L., and Ashwood-Smith, P. (Editors), "Generalized 362 MPLS - Signaling Functional Description", (work in progress) 364 [GMPLS-RSVP] Berger, L., and Ashwood-Smith, P. (Editors), 365 "Generalized MPLS Signaling - RSVP-TE Extensions", (work in 366 progress) 368 [GMPLS-ROUTING] Kompella, K., and Rekhter, Y. (Editors), "Routing 369 Extensions in Support of Generalized MPLS", (work in progress) 371 [OSPF-RESTART] Moy, J., "Hitless OSPF Restart", (work in progress) 373 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 374 Requirement Levels", BCP 14, RFC 2119, March 1997. 376 7. Security Considerations 378 The sub-TLVs proposed in this document do not raise any new security 379 concerns. 381 8. Acknowledgements 383 The authors would like to thank Suresh Katukam, Jonathan Lang, 384 Quaizar Vohra, and Alex Zinin for their comments on the draft. 386 9. Contributors 388 Ayan Banerjee 389 Calient Networks 390 5853 Rue Ferrari 391 San Jose, CA 95138 392 Phone: +1.408.972.3645 393 Email: abanerjee@calient.net 394 John Drake 395 Calient Networks 396 5853 Rue Ferrari 397 San Jose, CA 95138 398 Phone: (408) 972-3720 399 Email: jdrake@calient.net 401 Greg Bernstein 402 Ciena Corporation 403 10480 Ridgeview Court 404 Cupertino, CA 94014 405 Phone: (408) 366-4713 406 Email: greg@ciena.com 408 Don Fedyk 409 Nortel Networks Corp. 410 600 Technology Park Drive 411 Billerica, MA 01821 412 Phone: +1-978-288-4506 413 Email: dwfedyk@nortelnetworks.com 415 Eric Mannie 416 Independent Consultant 417 E-mail: eric_mannie@hotmail.com 419 Debanjan Saha 420 Tellium Optical Systems 421 2 Crescent Place 422 P.O. Box 901 423 Ocean Port, NJ 07757 424 Phone: (732) 923-4264 425 Email: dsaha@tellium.com 427 Vishal Sharma 428 Metanoia, Inc. 429 335 Elan Village Lane, Unit 203 430 San Jose, CA 95134-2539 431 Phone: +1 408-943-1794 432 Email: v.sharma@ieee.org 433 10. Authors' Information 435 Kireeti Kompella 436 Juniper Networks, Inc. 437 1194 N. Mathilda Ave 438 Sunnyvale, CA 94089 439 Email: kireeti@juniper.net 441 Yakov Rekhter 442 Juniper Networks, Inc. 443 1194 N. Mathilda Ave 444 Sunnyvale, CA 94089 445 Email: yakov@juniper.net 447 11. Intellectual Property Rights Notices 449 The IETF takes no position regarding the validity or scope of any 450 intellectual property or other rights that might be claimed to 451 pertain to the implementation or use of the technology described in 452 this document or the extent to which any license under such rights 453 might or might not be available; neither does it represent that it 454 has made any effort to identify any such rights. 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