idnits 2.17.1 draft-ietf-isis-te-app-03.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 == Line 567 has weird spacing: '...pecific y ...' == Line 574 has weird spacing: '...pecific n ...' -- The document date (November 14, 2017) is 2354 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references to lower-maturity documents in RFCs) ** Obsolete normative reference: RFC 7810 (Obsoleted by RFC 8570) == Outdated reference: A later version (-02) exists of draft-hegdeppsenak-isis-sr-flex-algo-01 == Outdated reference: A later version (-06) exists of draft-filsfils-spring-segment-routing-policy-03 Summary: 1 error (**), 0 flaws (~~), 5 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Networking Working Group L. Ginsberg 3 Internet-Draft P. Psenak 4 Intended status: Standards Track Cisco Systems 5 Expires: May 18, 2018 S. Previdi 6 Individual 7 W. Henderickx 8 Nokia 9 J. Drake 10 Juniper Networks 11 November 14, 2017 13 IS-IS TE Attributes per application 14 draft-ietf-isis-te-app-03.txt 16 Abstract 18 Existing traffic engineering related link attribute advertisements 19 have been defined and are used in RSVP-TE deployments. In cases 20 where multiple applications wish to make use of these link attributes 21 the current advertisements do not support application specific values 22 for a given attribute nor do they support indication of which 23 applications are using the advertised value for a given link. 25 This draft introduces new link attribute advertisements which address 26 both of these shortcomings. It also discusses backwards 27 compatibility issues and how to minimize duplicate advertisements in 28 the presence of routers which do not support the extensions defined 29 in this document. 31 Requirements Language 33 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 34 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 35 document are to be interpreted as described in RFC 2119 [RFC2119]. 37 Status of This Memo 39 This Internet-Draft is submitted in full conformance with the 40 provisions of BCP 78 and BCP 79. 42 Internet-Drafts are working documents of the Internet Engineering 43 Task Force (IETF). Note that other groups may also distribute 44 working documents as Internet-Drafts. The list of current Internet- 45 Drafts is at https://datatracker.ietf.org/drafts/current/. 47 Internet-Drafts are draft documents valid for a maximum of six months 48 and may be updated, replaced, or obsoleted by other documents at any 49 time. It is inappropriate to use Internet-Drafts as reference 50 material or to cite them other than as "work in progress." 52 This Internet-Draft will expire on May 18, 2018. 54 Copyright Notice 56 Copyright (c) 2017 IETF Trust and the persons identified as the 57 document authors. All rights reserved. 59 This document is subject to BCP 78 and the IETF Trust's Legal 60 Provisions Relating to IETF Documents 61 (https://trustee.ietf.org/license-info) in effect on the date of 62 publication of this document. Please review these documents 63 carefully, as they describe your rights and restrictions with respect 64 to this document. Code Components extracted from this document must 65 include Simplified BSD License text as described in Section 4.e of 66 the Trust Legal Provisions and are provided without warranty as 67 described in the Simplified BSD License. 69 Table of Contents 71 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 72 2. Requirements Discussion . . . . . . . . . . . . . . . . . . . 3 73 3. Legacy Advertisements . . . . . . . . . . . . . . . . . . . . 4 74 3.1. Legacy sub-TLVs . . . . . . . . . . . . . . . . . . . . . 4 75 3.2. Legacy SRLG Advertisements . . . . . . . . . . . . . . . 5 76 4. Advertising Application Specific Link Attributes . . . . . . 5 77 4.1. Application Identifier Bit Mask . . . . . . . . . . . . . 6 78 4.2. Application Specific Link Attributes sub-TLV . . . . . . 8 79 4.2.1. Special Considerations for Maximum Link Bandwidth . . 9 80 4.2.2. Special Considerations for Unreserved Bandwidth . . . 9 81 4.3. Application Specific SRLG TLV . . . . . . . . . . . . . . 9 82 5. Deployment Considerations . . . . . . . . . . . . . . . . . . 10 83 6. Attribute Advertisements and Enablement . . . . . . . . . . . 11 84 7. Interoperability, Backwards Compatibility and Migration 85 Concerns . . . . . . . . . . . . . . . . . . . . . . . . . . 12 86 7.1. RSVP-TE only deployments . . . . . . . . . . . . . . . . 12 87 7.2. Multiple Applications: Common Attributes with RSVP-TE . 12 88 7.3. Multiple Applications: All Attributes Not Shared w RSVP- 89 TE . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 90 7.4. Deprecating legacy advertisements . . . . . . . . . . . . 13 91 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 92 9. Security Considerations . . . . . . . . . . . . . . . . . . . 14 93 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15 94 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 15 95 11.1. Normative References . . . . . . . . . . . . . . . . . . 15 96 11.2. Informative References . . . . . . . . . . . . . . . . . 16 98 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 100 1. Introduction 102 Advertisement of link attributes by the Intermediate-System-to- 103 Intermediate-System (IS-IS) protocol in support of traffic 104 engineering (TE) was introduced by [RFC5305] and extended by 105 [RFC5307], [RFC6119], and [RFC7810]. Use of these extensions has 106 been associated with deployments supporting Traffic Engineering over 107 Multiprotocol Label Switching (MPLS) in the presence of Resource 108 Reservation Protocol (RSVP) - more succinctly referred to as RSVP-TE. 110 In recent years new applications have been introduced which have use 111 cases for many of the link attributes historically used by RSVP-TE. 112 Such applications include Segment Routing Traffic Engineering (SRTE) 113 and Loop Free Alternates (LFA). This has introduced ambiguity in 114 that if a deployment includes a mix of RSVP-TE support and SRTE 115 support (for example) it is not possible to unambiguously indicate 116 which advertisements are to be used by RSVP-TE and which 117 advertisements are to be used by SRTE. If the topologies are fully 118 congruent this may not be an issue, but any incongruence leads to 119 ambiguity. 121 An additional issue arises in cases where both applications are 122 supported on a link but the link attribute values associated with 123 each application differ. Current advertisements do not support 124 advertising application specific values for the same attribute on a 125 specific link. 127 This document defines extensions which address these issues. Also, 128 as evolution of use cases for link attributes can be expected to 129 continue in the years to come, this document defines a solution which 130 is easily extensible to the introduction of new applications and new 131 use cases. 133 2. Requirements Discussion 135 As stated previously, evolution of use cases for link attributes can 136 be expected to continue - so any discussion of existing use cases is 137 limited to requirements which are known at the time of this writing. 138 However, in order to determine the functionality required beyond what 139 already exists in IS-IS, it is only necessary to discuss use cases 140 which justify the key points identified in the introduction - which 141 are: 143 1. Support for indicating which applications are using the link 144 attribute advertisements on a link 146 2. Support for advertising application specific values for the same 147 attribute on a link 149 [RFC7855] discusses use cases/requirements for SR. Included among 150 these use cases is SRTE which is defined in [SR-POLICY]. If both 151 RSVP-TE and SRTE are deployed in a network, link attribute 152 advertisements can be used by one or both of these applications. As 153 there is no requirement for the link attributes advertised on a given 154 link used by SRTE to be identical to the link attributes advertised 155 on that same link used by RSVP-TE, there is a clear requirement to 156 indicate independently which link attribute advertisements are to be 157 used by each application. 159 As the number of applications which may wish to utilize link 160 attributes may grow in the future, an additional requirement is that 161 the extensions defined allow the association of additional 162 applications to link attributes without altering the format of the 163 advertisements or introducing new backwards compatibility issues. 165 Finally, there may still be many cases where a single attribute value 166 can be shared among multiple applications, so the solution must 167 minimize advertising duplicate link/attribute pairs whenever 168 possible. 170 3. Legacy Advertisements 172 There are existing advertisements used in support of RSVP-TE. These 173 advertisements include sub-TLVs for TLVs 22, 23, 141, 222, and 223 174 and TLVs for SRLG advertisement. 176 3.1. Legacy sub-TLVs 177 Sub-TLVs for TLVs 22, 23, 141, 222, and 223 179 Code Point/Attribute Name 180 -------------------------- 181 3 Administrative group (color) 182 9 Maximum link bandwidth 183 10 Maximum reservable link bandwidth 184 11 Unreserved bandwidth 185 14 Extended Administrative Group 186 33 Unidirectional Link Delay 187 34 Min/Max Unidirectional Link Delay 188 35 Unidirectional Delay Variation 189 36 Unidirectional Link Loss 190 37 Unidirectional Residual Bandwidth 191 38 Unidirectional Available Bandwidth 192 39 Unidirectional Utilized Bandwidth 194 3.2. Legacy SRLG Advertisements 196 TLV 138 GMPLS-SRLG 197 Supports links identified by IPv4 addresses and 198 unnumbered links 200 TLV 139 IPv6 SRLG 201 Supports links identified by IPv6 addresses 203 Note that [RFC6119] prohibits the use of TLV 139 when it is possible 204 to use TLV 138. 206 4. Advertising Application Specific Link Attributes 208 Two new code points are defined in support of Application Specific 209 Link Attribute Advertisements: 211 1) Application Specific Link Attributes sub-TLV for TLVs 22, 23, 141, 212 222, and 223 214 2)Application Specific Shared Risk Link Group (SRLG) TLV 216 In support of these new advertisements, an application bit mask is 217 defined which identifies the application(s) associated with a given 218 advertisement. 220 The following sections define the format of these new advertisements. 222 4.1. Application Identifier Bit Mask 224 Identification of the set of applications associated with link 225 attribute advertisements utilizes two bit masks. One bit mask is for 226 standard applications where the definition of each bit is defined in 227 a new IANA controlled registry. A second bit mask is for non- 228 standard User Defined Applications(UDAs). 230 The encoding defined below is used by both the Application Specific 231 Link Attributes sub-TLV and the Application Specific SRLG TLV. 233 0 1 2 3 4 5 6 7 234 +-+-+-+-+-+-+-+-+ 235 | SABML+F | 1 octet 236 +-+-+-+-+-+-+-+-+ 237 | UDABML+F | 1 octet 238 +-+-+-+-+-+-+-+-+ 239 | SABM ... 0 - 127 octets 240 +-+-+-+-+-+-+-+-+ 241 | UDABM ... 0 - 127 octets 242 +-+-+-+-+-+-+-+-+ 244 SABML+F (1 octet) 245 Standard Application Bit Mask Length/Flags 247 0 1 2 3 4 5 6 7 248 +-+-+-+-+-+-+-+-+ 249 |L| SA-Length | 250 +-+-+-+-+-+-+-+-+ 252 L-flag: Applications listed (both Standard and 253 User Defined) MUST use the legacy advertisements 254 for the corresponding link found in TLVs 22, 23, 255 141, 222, and 223 or TLV 138 or TLV 139 as appropriate. 257 SA-Length: Indicates the length in octets (0-127) of the Bit Mask 258 for Standard Applications. 260 UDABML+F (1 octet) 261 User Defined Application Bit Mask Length/Flags 263 0 1 2 3 4 5 6 7 264 +-+-+-+-+-+-+-+-+ 265 |R| UDA-Length | 266 +-+-+-+-+-+-+-+-+ 268 R: Reserved. Transmitted as 0 and ignored on receipt 269 UDA-Length: Indicates the length in octets (0-127) of the Bit Mask 270 for User Defined Applications. 272 SABM (variable length) 273 Standard Application Bit Mask 275 (SA-Length * 8) bits 277 This is omitted if SA-Length is 0. 279 0 1 2 3 4 5 6 7 ... 280 +-+-+-+-+-+-+-+-+... 281 |R|S|F|X| ... 282 +-+-+-+-+-+-+-+-+... 284 R-bit: RSVP-TE 286 S-bit: Segment Routing Traffic Engineering 288 F-bit: Loop Free Alternate 290 X-bit: Flex-Algo 292 UDABM (variable length) 293 User Defined Application Bit Mask 295 (UDA Length * 8) bits 297 0 1 2 3 4 5 6 7 ... 298 +-+-+-+-+-+-+-+-+... 299 | ... 300 +-+-+-+-+-+-+-+-+... 302 This is omitted if UDA-Length is 0. 304 NOTE: If both SA-length and UDA-Length are zero, then the 305 attributes associated with this attribute identifier bit mask 306 MAY be used by any Standard Application and any User Defined 307 Application. 309 Standard Application Bits are defined/sent starting with Bit 0. 310 Additional bit definitions that may be defined in the future SHOULD 311 be assigned in ascending bit order so as to minimize the number of 312 octets that will need to be transmitted. Undefined bits MUST be 313 transmitted as 0 and MUST be ignored on receipt. Bits that are NOT 314 transmitted MUST be treated as if they are set to 0 on receipt. 316 User Defined Application bits have no relationship to Standard 317 Application bits and are NOT managed by IANA or any other standards 318 body. It is recommended that bits are used starting with Bit 0 so as 319 to minimize the number of octets required to advertise all UDAs. 321 4.2. Application Specific Link Attributes sub-TLV 323 A new sub-TLV for TLVs 22, 23, 141, 222, and 223 is defined which 324 supports specification of the applications and application specific 325 attribute values. 327 Type: 16 (suggested value - to be assigned by IANA) 328 Length: Variable (1 octet) 329 Value: 331 Application Bit Mask (as defined in Section 3.1) 333 Link Attribute sub-sub-TLVs - format matches the 334 existing formats defined in [RFC5305] and [RFC7810] 336 When the L-flag is set in the Application Identifiers, all of the 337 applications specified in the bit mask MUST use the link attribute 338 sub-TLV advertisements listed in Section 3.1 for the corresponding 339 link. Application specific link attribute sub-sub-TLVs for the 340 corresponding link attributes MUST NOT be advertised for the set of 341 applications specified in the Standard/User Application Bit Masks and 342 all such advertisements MUST be ignored on receipt. 344 Multiple sub-TLVs for the same link MAY be advertised. When multiple 345 sub-TLVs for the same link are advertised, they SHOULD advertise non- 346 conflicting application/attribute pairs. A conflict exists when the 347 same application is associated with two different values of the same 348 link attribute for a given link. In cases where conflicting values 349 for the same application/attribute/link are advertised all the 350 conflicting values MUST be ignored. 352 For a given application, the setting of the L-flag MUST be the same 353 in all sub-TLVs for a given link. In cases where this constraint is 354 violated, the L-flag MUST be considered set for this application. 356 A new registry of sub-sub-TLVs is to be created by IANA which defines 357 the link attribute sub-sub-TLV code points. A sub-sub-TLV is defined 358 for each of the existing sub-TLVs listed in Section 3.1 except as 359 noted below. The format of the sub-sub-TLVs matches the format of 360 the corresponding legacy sub-TLV and IANA is requested to assign the 361 legacy sub-TLV identifer to the corresponding sub-sub-TLV. 363 4.2.1. Special Considerations for Maximum Link Bandwidth 365 Maximum link bandwidth is an application independent attribute of the 366 link. When advertised using the Application Specific Link Attributes 367 sub-TLV, multiple values for the same link MUST NOT be advertised. 368 This can be accomplished most efficiently by having a single 369 advertisement for a given link where the Application Bit Mask 370 identifies all the applications which are making use of the value for 371 that link. 373 It is also possible to advertise the same value for a given link 374 multiple times with disjoint sets of applications specified in the 375 Application Bit Mask. This is less efficient but still valid. 377 If different values for Maximum Link Bandwidth for a given link are 378 advertised, all values MUST be ignored. 380 4.2.2. Special Considerations for Unreserved Bandwidth 382 Unreserved bandwidth is an attribute specific to RSVP. When 383 advertised using the Application Specific Link Attributes sub-TLV, 384 bits other than the RSVP-TE(R-bit) MUST NOT be set in the Application 385 Bit Mask. If an advertisement of Unreserved Bandwidth is received 386 with bits other than the RSVP-TE bit set, the advertisement MUST be 387 ignored. 389 4.3. Application Specific SRLG TLV 391 A new TLV is defined to advertise application specific SRLGs for a 392 given link. Although similar in functionality to TLV 138 (defined by 393 [RFC5307]) and TLV 139 (defined by [RFC6119], a single TLV provides 394 support for IPv4, IPv6, and unnumbered identifiers for a link. 395 Unlike TLVs 138/139, it utilizes sub-TLVs to encode the link 396 identifiers in order to provide the flexible formatting required to 397 support multiple link identifier types. 399 Type: 238 (Suggested value - to be assigned by IANA) 400 Length: Number of octets in the value field (1 octet) 401 Value: 402 Neighbor System-ID + pseudo-node ID (7 octets) 403 Application Bit Mask (as defined in Section 3.1) 404 Length of sub-TLVs (1 octet) 405 Link Identifier sub-TLVs (variable) 406 0 or more SRLG Values (Each value is 4 octets) 408 The following Link Identifier sub-TLVs are defined. The type 409 values are suggested and will be assigned by IANA - but as 410 the formats are identical to existing sub-TLVs defined for 411 TLVs 22, 23, 141, 222, and 223 the use of the suggested sub-TLV 412 types is strongly encouraged. 414 Type Description 415 4 Link Local/Remote Identifiers (see [RFC5307]) 416 6 IPv4 interface address (see [RFC5305]) 417 8 IPv4 neighbor address (see [RFC5305]) 418 12 IPv6 Interface Address (see [RFC6119]) 419 13 IPv6 Neighbor Address (see [RFC6119]) 421 At least one set of link identifiers (IPv4, IPv6, or unnumbered) MUST 422 be present. TLVs which do not meet this requirement MUST be ignored. 424 Multiple TLVs for the same link MAY be advertised. 426 When the L-flag is set in the Application Identifiers, SRLG values 427 MUST NOT be included in the TLV. Any SRLG values which are 428 advertised MUST be ignored. Based on the link identifiers advertised 429 the corresponding legacy TLV (see Section 3.2) can be identified and 430 the SRLG values advertised in the legacy TLV MUST be used by the set 431 of applications specified in the Application Bit Mask. 433 For a given application, the setting of the L-flag MUST be the same 434 in all TLVs for a given link. In cases where this constraint is 435 violated, the L-flag MUST be considered set for this application. 437 5. Deployment Considerations 439 If link attributes are advertised associated with zero length 440 application bit masks for both standard applications and user defined 441 applications, then that set of link attributes MAY be used by any 442 application. If support for a new application is introduced on any 443 node in a network in the presence of such advertisements, these 444 advertisements MAY be used by the new application. If this is not 445 what is intended, then existing advertisements MUST be readvertised 446 with an explicit set of applications specified before a new 447 application is introduced. 449 6. Attribute Advertisements and Enablement 451 This document defines extensions to support the advertisement of 452 application specific link attributes. 454 Whether the presence of link attribute advertisements for a given 455 application indicates that the application is enabled on that link 456 depends upon the application. Similarly, whether the absence of link 457 attribute advertisements indicates that the application is not 458 enabled depends upon the application. 460 In the case of RSVP-TE, the advertisement of application specific 461 link attributes implies that RSVP is enabled on that link. 463 In the case of SRTE, advertisement of application specific link 464 attributes does NOT indicate enablement of SRTE. The advertisements 465 are only used to support constraints which may be applied when 466 specifying an explicit path. SRTE is implicitly enabled on all links 467 which are part of the Segment Routing enabled topology independent of 468 the existence of link attribute advertisements 470 In the case of LFA, advertisement of application specific link 471 attributes does NOT indicate enablement of LFA on that link. 472 Enablement is controlled by local configuration. 474 In the case of Flex-Algo, advertisement of application specific link 475 attributes does NOT indicate enablement of Flex-Algo. Rather the 476 attributes are used to determine what links are included/excluded in 477 the algorithm specific constrained SPF. This is fully specified in 478 [FLEX-ALGO]. 480 If, in the future, additional standard applications are defined to 481 use this mechanism, the specification defining this use MUST define 482 the relationship between application specific link attribute 483 advertisements and enablement for that application. 485 This document allows the advertisement of application specific link 486 attributes with no application identifiers i.e., both the Standard 487 Application Bit Mask and the User Defined Application Bit Mask are 488 not present (See Section 4.1). This supports the use of the link 489 attribute by any application. In the presence of an application 490 where the advertisement of link attribute advertisements is used to 491 infer the enablement of an application on that link (e.g., RSVP-TE), 492 the absence of the application identifier leaves ambiguous whether 493 that application is enabled on such a link. This needs to be 494 considered when making use of the "any application" encoding. 496 7. Interoperability, Backwards Compatibility and Migration Concerns 498 Existing deployments of RSVP-TE utilize the legacy advertisements 499 listed in Section 3. Routers which do not support the extensions 500 defined in this document will only process legacy advertisements and 501 are likely to infer that RSVP-TE is enabled on the links for which 502 legacy advertisements exist. It is expected that deployments using 503 the legacy advertisements will persist for a significant period of 504 time - therefore deployments using the extensions defined in this 505 document must be able to co-exist with use of the legacy 506 advertisements by routers which do not support the extensions defined 507 in this document. The following sub-sections discuss 508 interoperability and backwards compatibility concerns for a number of 509 deployment scenarios. 511 Note that in all cases the defined strategy can be employed on a per 512 link basis. 514 7.1. RSVP-TE only deployments 516 In deployments where RSVP-TE is the only application utilizing link 517 attribute advertisements, use of the the legacy advertisements can 518 continue without change. 520 7.2. Multiple Applications: Common Attributes with RSVP-TE 522 In cases where multiple applications are utilizing a given link, one 523 of the applications is RSVP-TE, and all link attributes for a given 524 link are common to the set of applications utilizing that link, 525 interoperability is achieved by using legacy advertisements and 526 sending application specific advertisements with L-bit set and no 527 link attribute values. This avoids duplication of link attribute 528 advertisements. 530 7.3. Multiple Applications: All Attributes Not Shared w RSVP-TE 532 In cases where one or more applications other than RSVP-TE are 533 utilizing a given link and one or more link attribute values are NOT 534 shared with RSVP-TE, it is necessary to use application specific 535 advertisements as defined in this document. Attributes for 536 applications other than RSVP-TE MUST be advertised using application 537 specific advertisements which have the L-bit clear. In cases where 538 some link attributes are shared with RSVP-TE, this requires duplicate 539 advertisements for those attributes. 541 The discussion in this section applies to cases where RSVP-TE is NOT 542 using any advertised attributes on a link and to cases where RSVP-TE 543 is using some link attribute advertisements on the link but some link 544 attributes cannot be shared with RSVP-TE. 546 7.4. Deprecating legacy advertisements 548 The extensions defined in this document support RSVP-TE as one of the 549 supported applications - so a long term goal for deployments would be 550 to deprecate use of the legacy advertisements in support of RSVP-TE. 551 This can be done in the following step-wise manner: 553 1)Upgrade all routers to support extensions in this document 555 2)Readvertise all legacy link attributes using application specific 556 advertisements with L-bit clear and R-bit set. 558 3)Remove legacy advertisements 560 8. IANA Considerations 562 This document defines a new sub-TLV for TLVs 22, 23, 141, 222, and 563 223. 565 Type Description 22 23 141 222 223 566 ---- --------------------- --- --- --- --- --- 567 16 Application Specific y y y y y 568 Link Attributes 570 This document defines one new TLV: 572 Type Description IIH SNP LSP Purge 573 ---- --------------------- --- --- --- ----- 574 238 Application Specific n n y n 575 SRLG 577 This document requests a new IANA registry be created to control the 578 assignment of sub-sub-TLV codepoints for the Application Specific 579 Link Attributes sub-TLV. The suggested name of the new registry is 580 "sub-sub-TLV code points for application link attributes". The 581 registration procedure is "Expert Review" as defined in [RFC8126]. 582 The following assignments are made by this document: 584 Type Description 585 --------------------------------------------------------- 586 3 Administrative group (color) 587 9 Maximum link bandwidth 588 10 Maximum reservable link bandwidth 589 11 Unreserved bandwidth 590 14 Extended Administrative Group 591 33 Unidirectional Link Delay 592 34 Min/Max Unidirectional Link Delay 593 35 Unidirectional Delay Variation 594 36 Unidirectional Link Loss 595 37 Unidirectional Residual Bandwidth 596 38 Unidirectional Available Bandwidth 597 39 Unidirectional Utilized Bandwidth 599 This document requests a new IANA registry be created to control the 600 assignment of application bit identifiers. The suggested name of the 601 new registry is "Link Attribute Applications". The registration 602 procedure is "Expert Review" as defined in [RFC8126]. The following 603 assignments are made by this document: 605 Bit # Name 606 --------------------------------------------------------- 607 0 RSVP-TE (R-bit) 608 1 Segment Routing Traffic Engineering (S-bit) 609 2 Loop Free Alternate (F-bit) 610 3 Flex Algorithm (X-bit) 612 This document requests a new IANA registry be created to control the 613 assignment of sub-TLV types for the application specific SRLG TLV. 614 The suggested name of the new registry is "Sub-TLVs for TLV 238". 615 The registration procedure is "Expert Review" as defined in 616 [RFC8126]. The following assignments are made by this document: 618 Value Description 619 --------------------------------------------------------- 620 4 Link Local/Remote Identifiers (see [RFC5307]) 621 6 IPv4 interface address (see [RFC5305]) 622 8 IPv4 neighbor address (see [RFC5305]) 623 12 IPv6 Interface Address (see [RFC6119]) 624 13 IPv6 Neighbor Address (see [RFC6119]) 626 9. Security Considerations 628 Security concerns for IS-IS are addressed in [ISO10589, [RFC5304], 629 and [RFC5310]. 631 10. Acknowledgements 633 The authors would like to thank Eric Rosen and Acee Lindem for their 634 careful review and content suggestions. 636 11. References 638 11.1. Normative References 640 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 641 Requirement Levels", BCP 14, RFC 2119, 642 DOI 10.17487/RFC2119, March 1997, 643 . 645 [RFC5304] Li, T. and R. Atkinson, "IS-IS Cryptographic 646 Authentication", RFC 5304, DOI 10.17487/RFC5304, October 647 2008, . 649 [RFC5305] Li, T. and H. Smit, "IS-IS Extensions for Traffic 650 Engineering", RFC 5305, DOI 10.17487/RFC5305, October 651 2008, . 653 [RFC5307] Kompella, K., Ed. and Y. Rekhter, Ed., "IS-IS Extensions 654 in Support of Generalized Multi-Protocol Label Switching 655 (GMPLS)", RFC 5307, DOI 10.17487/RFC5307, October 2008, 656 . 658 [RFC5310] Bhatia, M., Manral, V., Li, T., Atkinson, R., White, R., 659 and M. Fanto, "IS-IS Generic Cryptographic 660 Authentication", RFC 5310, DOI 10.17487/RFC5310, February 661 2009, . 663 [RFC6119] Harrison, J., Berger, J., and M. Bartlett, "IPv6 Traffic 664 Engineering in IS-IS", RFC 6119, DOI 10.17487/RFC6119, 665 February 2011, . 667 [RFC7810] Previdi, S., Ed., Giacalone, S., Ward, D., Drake, J., and 668 Q. Wu, "IS-IS Traffic Engineering (TE) Metric Extensions", 669 RFC 7810, DOI 10.17487/RFC7810, May 2016, 670 . 672 [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for 673 Writing an IANA Considerations Section in RFCs", BCP 26, 674 RFC 8126, DOI 10.17487/RFC8126, June 2017, 675 . 677 11.2. Informative References 679 [FLEX-ALGO] 680 "ISIS Segment Routing Flexible Algorithm, draft- 681 hegdeppsenak-isis-sr-flex-algo-01(work in progress)", 682 October 2017. 684 [RFC7855] Previdi, S., Ed., Filsfils, C., Ed., Decraene, B., 685 Litkowski, S., Horneffer, M., and R. Shakir, "Source 686 Packet Routing in Networking (SPRING) Problem Statement 687 and Requirements", RFC 7855, DOI 10.17487/RFC7855, May 688 2016, . 690 [SR-POLICY] 691 "Segment Routing Policy for Traffic Engineering, draft- 692 filsfils-spring-segment-routing-policy-03(work in 693 progress)", Oct 2017. 695 Authors' Addresses 697 Les Ginsberg 698 Cisco Systems 699 821 Alder Drive 700 Milpitas, CA 95035 701 USA 703 Email: ginsberg@cisco.com 705 Peter Psenak 706 Cisco Systems 707 Apollo Business Center Mlynske nivy 43 708 Bratislava 821 09 709 Slovakia 711 Email: ppsenak@cisco.com 713 Stefano Previdi 714 Individual 716 Email: stefano@previdi.net 717 Wim Henderickx 718 Nokia 719 Copernicuslaan 50 720 Antwerp 2018 94089 721 Belgium 723 Email: wim.henderickx@nokia.com 725 John Drake 726 Juniper Networks 728 Email: jdrake@juniper.net