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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references to lower-maturity documents in RFCs) ** Obsolete normative reference: RFC 7042 (Obsoleted by RFC 9542) == Outdated reference: A later version (-12) exists of draft-ietf-lsvr-l3dl-02 ** Downref: Normative reference to an Experimental draft: draft-ietf-lsvr-l3dl (ref. 'I-D.ietf-lsvr-l3dl') Summary: 2 errors (**), 0 flaws (~~), 2 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 1 LSVR P. Congdon 2 Internet Draft Tallac Networks, Inc. 3 Intended status: Standards Track P. Bottorff 4 Expires: April 21, 2020 Aruba 5 October 22, 2019 7 LSVR IETF Organizationally Specific TLVs for IEEE Std 802.1AB (LLDP) 8 draft-congdon-lsvr-lldp-tlvs-00.txt 10 Status of this Memo 12 This Internet-Draft is submitted in full conformance with the 13 provisions of BCP 78 and BCP 79. 15 Internet-Drafts are working documents of the Internet Engineering 16 Task Force (IETF), its areas, and its working groups. Note that 17 other groups may also distribute working documents as Internet- 18 Drafts. 20 Internet-Drafts are draft documents valid for a maximum of six 21 months and may be updated, replaced, or obsoleted by other documents 22 at any time. It is inappropriate to use Internet-Drafts as 23 reference material or to cite them other than as "work in progress." 25 The list of current Internet-Drafts can be accessed at 26 http://www.ietf.org/ietf/1id-abstracts.txt 28 The list of Internet-Draft Shadow Directories can be accessed at 29 http://www.ietf.org/shadow.html 31 This Internet-Draft will expire on April 22, 2009. 33 Copyright Notice 35 Copyright (c) 2019 IETF Trust and the persons identified as the 36 document authors. All rights reserved. 38 This document is subject to BCP 78 and the IETF Trust's Legal 39 Provisions Relating to IETF Documents 40 (http://trustee.ietf.org/license-info) in effect on the date of 41 publication of this document. Please review these documents 42 carefully, as they describe your rights and restrictions with 43 respect to this document. Code Components extracted from this 44 document must include Simplified BSD License text as described in 45 Section 4.e of the Trust Legal Provisions and are provided without 46 warranty as described in the Simplified BSD License. 48 Abstract 50 IEEE Std 802.1AB, commonly known as the Link Layer Discovery 51 Protocol (LLDP), provides a means for individual organizations to 52 define their own Type-Length-Value (TLV) objects for exchange over 53 the protocol. The IETF is a standards development organization with 54 an IANA OUI (RFC 7042) that can be used in LLDP organizationally 55 specific TLVs. This document specifies IETF Organizationally 56 Specific TLVs that support LSVR protocols. 58 Table of Contents 60 1. Introduction...................................................3 61 2. Conventions....................................................4 62 3. Abbreviations..................................................4 63 4. LLDP Organizationally Specific TLVs............................4 64 4.1. Type......................................................5 65 4.2. Length....................................................5 66 4.3. Organizationally Unique Identifier........................5 67 4.4. Subtype...................................................5 68 4.5. Information...............................................5 69 5. IETF Organizationally Specific TLVs............................5 70 5.1. Logical Link Endpoint Identifier Attributes TLV...........6 71 5.1.1. LLEI Length..........................................6 72 5.1.2. LLEI.................................................6 73 5.1.3. AttrCount............................................7 74 5.1.4. Attribute List.......................................7 75 5.1.5. Logical Link Endpoint Identifier TLV usage rules.....7 76 5.2. IPv4 Announcement TLV.....................................7 77 5.2.1. LLEI Length..........................................7 78 5.2.2. LLEI.................................................8 79 5.2.3. Encaps Flags.........................................8 80 5.2.3.1. Announce........................................8 81 5.2.3.2. Primary.........................................8 82 5.2.3.3. Under/Over......................................8 83 5.2.3.4. Loopback........................................8 84 5.2.4. IPv4 Address.........................................9 85 5.2.5. Prefix Length........................................9 86 5.2.6. IPv4 Announcement TLV usage rules....................9 87 5.3. IPv6 Announcement TLV.....................................9 88 5.3.1. LLEI Length.........................................10 89 5.3.2. LLEI................................................10 90 5.3.3. Encaps Flags........................................10 91 5.3.4. IPv6 Address........................................10 92 5.3.5. Prefix Length.......................................10 93 5.3.6. IPv6 Announcement TLV usage rules...................11 95 5.4. MPLS IPv4 Announcement TLV...............................11 96 5.4.1. LLEI Length.........................................11 97 5.4.2. LLEI................................................11 98 5.4.3. Encaps Flags........................................11 99 5.4.4. MPLS Label List.....................................12 100 5.4.4.1. Label Count....................................12 101 5.4.4.2. Label..........................................12 102 5.4.4.3. Exp............................................12 103 5.4.4.4. S..............................................12 104 5.4.5. IPv4 Address........................................12 105 5.4.6. Prefix Length.......................................13 106 5.4.7. IPv4 Announcement TLV usage rules...................13 107 5.5. MPLS IPv6 Announcement TLV...............................13 108 5.5.1. LLEI Length.........................................13 109 5.5.2. LLEI................................................14 110 5.5.3. Encaps Flags........................................14 111 5.5.4. MPLS Label List.....................................14 112 5.5.5. IPv6 Address........................................14 113 5.5.6. Prefix Length.......................................14 114 5.5.7. MPLS IPv6 Announcement TLV usage rules..............14 115 6. Security Considerations.......................................14 116 7. IANA Considerations...........................................14 117 8. Conclusions...................................................14 118 9. References....................................................15 119 9.1. Normative References.....................................15 120 9.2. Informative References...................................15 121 10. Acknowledgments..............................................15 123 1. Introduction 125 IEEE Std 802.1AB [802.1AB], commonly known as the Link Layer 126 Discovery Protocol (LLDP), provides a means for individual 127 organizations to define their own Type-Length-Value (TLV) objects 128 for exchange over the protocol. TLVs that belong to an organization 129 are identified by the inclusion of the organization's OUI and an 130 organizationally defined subtype in the initial octets of the 131 information field. 133 The IETF is a standards development organization with an IANA OUI. 134 The usage and considerations for this OUI are discussed in 135 [RFC7042]. The IANA OUI can be used in LLDP organizationally 136 specific TLVs. 138 The LSVR working group is specifying protocols that need to discover 139 IP Layer 3 attributes about links, encapsulations and neighbors. 140 This document specifies IETF Organizationally Specific TLVs that 141 carry the necessary discovery attributes for LSVR working group 142 protocols. 144 The IEEE 802 recently approved project P802.1ABdh [802.1ABdh] to 145 amend LLDP with the ability to transmit and receive a set of TLVs 146 that exceed the space available in a single frame. Among other 147 objectives, this project is intended to allow LLDP to better suit 148 the needs of LSVR and other IETF working groups. 150 2. Conventions 152 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 153 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 154 document are to be interpreted as described in RFC 2119 [RFC2119]. 156 In this document, these words will appear with that interpretation 157 only when in ALL CAPS. Lower case uses of these words are not to be 158 interpreted as carrying significance described in RFC 2119. 160 3. Abbreviations 162 LLDP - The Link Layer Discovery 164 TLV - Type-Length-Value 166 4. LLDP Organizationally Specific TLVs 168 IEEE Std 802.1AB defines the format of the organizationally specific 169 TLVs. The format is redrawn here for convenience. 171 0 1 2 3 172 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 1 173 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 174 | Type=127 | Length | Organizationally Unique ~ 175 | 7 bits | 9 bits | Identifier (OUI) 3 octets ~ 176 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 177 ~ OUI | Subtype | Information ~ 178 ~ continued | 1 octet | 0 <= n <= 507 octets ~ 179 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 180 ~ Information... ~ 181 ~ ~ 182 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 184 Figure 1 LLDP Organizationally Specific TLV Format 186 4.1. Type 188 The Type field is 7 bits in length and is set to the value of 127 189 indicating the TLV type is an Organizationally Specific TLV. 191 4.2. Length 193 The Length field contains the length of the TLV specific 194 information, the OUI and subtype. The Length is from 4 to 511 195 octets. 197 4.3. Organizationally Unique Identifier 199 The Organizationally Unique Identifier indicates the organization 200 specifying the TLV. For IETF use, this field is the IANA OUI as 201 discussed in RFC 7042 and has the hex value of 00-00-5E. 203 4.4. Subtype 205 The Subtype field indicates the specific IETF Organizationally 206 Specific TLV. The format of the information string is dependent 207 upon the Subtype field. The following subtypes have been defined: 209 Subtype Name 210 ------- ----- 211 0 Logical Link Endpoint Identifier Attributes 212 1 IPv4 Announcement 213 2 IPv6 Announcement 214 3 MPLS IPv4 Announcement 215 4 MPLS IPv6 Announcement 216 5-255 Reserved 218 The specific TLV format for each subtype is defined in section 5. 220 4.5. Information 222 The Information field contains the octets that are specific to the 223 Organizationally Specific TLV. The field length is between 0 and 224 507 octets. 226 5. IETF Organizationally Specific TLVs 228 This section defines the format for the IETF Organizationally 229 Specific TLVs. The contents of the TLVs are modeled after the TLV 230 PDUs of the L3DL protocol specified by the LSVR working group in [I- 231 D.ietf-lsvr-l3dl]. 233 Each TLV definition starts with the same first four fields that are 234 described once here. The Type field SHALL be 127; the Length field 235 SHALL be the length in octets of the LLDP TLV information string 236 which starts immediately after the Length field; the OUI field SHALL 237 be 00-00-0E and the Subtype field SHALL be one of the named values 238 shown in the table of Section 4.4. The remaining fields of each TLV 239 are specified in the section for the IETF Organizationally Specific 240 TLV. 242 5.1. Logical Link Endpoint Identifier Attributes TLV 244 The Logical Link Endpoint Identifier (LLEI) Attributes TLV carries 245 an LLEI and a list of operator-defined attributes. An LLEI is a 246 variable length descriptor which is unique to a single logical link 247 endpoint in the topology. An LLEI and its use in discovering a 248 logical link are defined in [I-D.ietf-lsvr-l3dl]. 250 A router or switch supporting LSVR protocols MAY include the Logical 251 Link Endpoint Identifier Attributes TLV in LLDPDU transmissions. 252 The format of the Logical Link Endpoint Identifier Attributes TLV is 253 shown in Figure 2. 255 0 1 2 3 256 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 1 257 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 258 | Type=127 | Length | OUI = 00-00-5E ~ 259 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 260 ~ | Subtype = 0 | LLEI Length | ~ 261 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 262 ~ LLEI | AttrCount | 263 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 264 | Attribute List... | 265 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 267 Figure 2 Logical Link Endpoint Identifier Attributes TLV 269 5.1.1. LLEI Length 271 The LLEI Length is 1 octet and specifies the length in octets of the 272 LLEI field. The LLEI Length MUST NOT be 0. 274 5.1.2. LLEI 276 The LLEI is the variable length descriptor which is unique to a 277 single logical link endpoint in the topology. Possible formats for 278 the LLEI are discussed in [I-D.ietf-lsvr-l3dl]. 280 5.1.3. AttrCount 282 The AttrCount field is 1 octet and specifies the number of 283 attributes in the Attribute List. If there are no attributes in the 284 Attribute List, then AttrCount SHALL be 0. 286 5.1.4. Attribute List 288 The Attribute List is a sequence of single octets, the syntax and 289 semantics of which are local to an operator or datacenter. 291 5.1.5. Logical Link Endpoint Identifier TLV usage rules 293 An LLDPDU SHOULD contain at most one Logical Link Endpoint 294 Identifier Attributes TLV for each unique LLEI operating on a 295 physical port. 297 5.2. IPv4 Announcement TLV 299 The IPv4 Announcement TLV describes a device's ability to exchange 300 IPv4 packets on one or more subnets. It does so by announcing the 301 interface's addresses and the corresponding prefix lengths. 302 Multiple tuples of IPv4 address information can be announced in a 303 single TLV, each tuple with its own set of encapsulation flags, 304 address and prefix length. The format of the IPv4 Announcement TLV 305 is as follows: 307 0 1 2 3 308 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 1 309 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 310 | Type=127 | Length | OUI = 00-00-5E ~ 311 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 312 ~ | Subtype = 1 | LLEI Length | ~ 313 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 314 ~ LLEI | Encaps Flags | 315 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 316 ~ IPv4 Address | 317 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 318 | Prefix Length | more... | 319 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 321 Figure 3 IPv4 Announcement TLV 323 5.2.1. LLEI Length 325 The LLEI Length is the same as specified in section 5.1.1. 327 5.2.2. LLEI 329 The LLEI is the same as specified in section 5.1.2. 331 5.2.3. Encaps Flags 333 The Encaps Flags specify attributes about the IPv4 address being 334 announced and are compatible with the Encapsulation Flags defined 335 [I-D.ietf-lsvr-l3dl]. The Encaps Flags have the following format: 337 0 1 2 3 4 ... 7 338 +------------+------------+------------+------------+-----------+ 339 | Announce | Primary | Under/Over | Loopback | Reserved | 340 +------------+------------+------------+------------+-----------+ 342 Figure 4 Encapsulation Flags 344 5.2.3.1. Announce 346 The Announce flag bit SHALL always be set to 1. [I-D.ietf-lsvr-l3dl] 347 defines this bit as an Announce/Withdraw bit to allow encapsulations 348 to be both announced and withdrawn by the L3DL protocol. Old 349 encapsulations are withdrawn in LLDP by simply excluding them in the 350 next transmission of an LLDPDU. 352 5.2.3.2. Primary 354 The Primary flag bit indicates that the encapsulation interface is a 355 primary interface. The value of 1 indicates the interface is 356 primary and the value of 0 indicates it is not. If the LLEI has 357 multiple addresses for an encapsulation type, one and only one 358 address SHOULD be marked as primary. 360 5.2.3.3. Under/Over 362 The Under/Over flag bit indicates if the interface address is for an 363 underlay interface or an overlay interface. The value of 1 364 indicates the interface is an underlay and the value of 0 indicates 365 it is an overlay. 367 5.2.3.4. Loopback 369 The Loopback flag bit indicates if the interface address is a 370 loopback address. Loopback addresses are generally not seen 371 directly on an external interface. One or more loopback addresses 372 MAY be announced. The value of 1 indicates that the interface 373 address is a loopback address and the value of 0 indicates it is 374 not. 376 5.2.4. IPv4 Address 378 The IPv4 Address field holds the IPv4 address to be announced. 380 5.2.5. Prefix Length 382 The Prefix Length field indicates the number of bits in the IPv4 383 Address that represent the IPv4 prefix for the subnet (network 384 portion of the address). 386 5.2.6. IPv4 Announcement TLV usage rules 388 An LLDPDU MAY contain multiple IPv4 Announcement TLVs, however, the 389 encapsulation flags, IPv4 address and prefix length tuple for a 390 specific IPv4 address MUST only appear once in the LLDPDU. 392 5.3. IPv6 Announcement TLV 394 The IPv6 Announcement TLV describes a device's ability to exchange 395 IPv6 packets on one or more subnets. It does so by announcing the 396 interface's addresses and the corresponding prefix lengths. 397 Multiple tuples of IPv6 address information can be announced in a 398 single TLV, each tuple with its own set of encapsulation flags, 399 address and prefix length. The format of the IPv6 Announcement TLV 400 is as follows: 402 0 1 2 3 403 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 1 404 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 405 | Type=127 | Length | OUI = 00-00-5E ~ 406 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 407 ~ | Subtype = 2 | LLEI Length | ~ 408 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 409 ~ LLEI | | 410 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + 411 | | 412 + + 413 | | 414 + IPv6 Address + 415 | | 416 + +-+-+-+-+-+-+-+-+ 417 | | Prefix Length | 418 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 419 | more... | 420 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 422 Figure 5 IPv6 Announcement TLV 424 5.3.1. LLEI Length 426 The LLEI Length is the same as specified in section 5.1.1. 428 5.3.2. LLEI 430 The LLEI is the same as specified in section 5.1.2. 432 5.3.3. Encaps Flags 434 The Encaps Flags are the same flags specified in section 5.2.3 436 5.3.4. IPv6 Address 438 The IPv6 Address field holds the IPv6 address to be announced. 440 5.3.5. Prefix Length 442 The Prefix Length field indicates the number of bits in the IPv6 443 Address that represent the IPv6 prefix for the subnet (network 444 portion of the address). 446 5.3.6. IPv6 Announcement TLV usage rules 448 An LLDPDU MAY contain multiple IPv6 Announcement TLVs, however, the 449 encapsulation flags, IPv6 address and prefix length tuple for a 450 specific IPv6 address MUST only appear once in the LLDPDU. 452 5.4. MPLS IPv4 Announcement TLV 454 The MPLS IPv4 Encapsulation describes a logical link's ability to 455 exchange labeled IPv4 packets on one or more subnets. It does so by 456 stating the interface's addresses the corresponding prefix lengths, 457 and the corresponding labels which will be accepted for each 458 address. The format of the MPLS IPv4 Announcement TLV is as 459 follows: 461 0 1 2 3 462 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 1 463 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 464 | Type=127 | Length | OUI = 00-00-5E ~ 465 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 466 ~ | Subtype = 3 | LLEI Length | ~ 467 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 468 ~ LLEI | ~ 469 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 470 ~ MPLS Label List... | ~ 471 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 472 ~ IPv4 Address | Prefix Length | 473 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 474 | more... | 475 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 477 Figure 6 MPLS IPv4 Announcement TLV 479 5.4.1. LLEI Length 481 The LLEI Length is the same as specified in section 5.1.1. 483 5.4.2. LLEI 485 The LLEI is the same as specified in section 5.1.2. 487 5.4.3. Encaps Flags 489 The Encaps Flags are the same flags specified in section 5.2.3 491 5.4.4. MPLS Label List 493 The MPLS Label List is a variable length field that contains the 494 label stack, see [RFC3032], that the sender will accept for the 495 prefix to which the list is attached. The format of the MPLS Label 496 List is as follows: 498 0 1 2 3 499 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 1 500 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 501 | Label Count | Label | Exp |S| 502 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 503 | Label | Exp |S| more ... | 504 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 505 Figure 7 MPLS Label List 507 5.4.4.1. Label Count 509 The number of label stack entries that are included in the list. 510 Each label stack entry has a label, experimental use bits and the 511 bottom of stack indicator. The Label Count MUST NOT be 0. 513 <> 516 5.4.4.2. Label 518 The Label field is the 20-bit value of the label. 520 5.4.4.3. Exp 522 The Exp field is a 3-bit value reserved for experimental use. 524 5.4.4.4. S 526 The S field is a single bit that indicates the last entry in the 527 label stack. The bit is set to 1 for the last entry and 0 for all 528 other entries in the list. 530 5.4.5. IPv4 Address 532 The IPv4 Address field holds the IPv4 address to be announced. 534 5.4.6. Prefix Length 536 The Prefix Length field indicates the number of bits in the IPv4 537 Address that represent the IPv4 prefix for the subnet (network 538 portion of the address). 540 5.4.7. IPv4 Announcement TLV usage rules 542 An LLDPDU MAY contain multiple MPLS IPv4 Announcement TLVs, however, 543 the encapsulation flags, label list, IPv4 address and prefix length 544 tuple for a specific IPv4 address MUST only appear once in the 545 LLDPDU. 547 5.5. MPLS IPv6 Announcement TLV 549 The MPLS IPv6 Encapsulation describes a logical link's ability to 550 exchange labeled IPv6 packets on one or more subnets. It does so by 551 stating the interface's addresses the corresponding prefix lengths, 552 and the corresponding labels which will be accepted for each 553 address. The format of the MPLS IPv6 Announcement TLV is as 554 follows: 556 0 1 2 3 557 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 1 558 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 559 | Type=127 | Length | OUI = 00-00-5E ~ 560 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 561 ~ | Subtype = 4 | LLEI Length | ~ 562 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 563 ~ LLEI | ~ 564 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 565 | MPLS Label List... | | 566 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + 567 | | 568 + + 569 | IPV6 Address | 570 + +-+-+-+-+-+-+-+-+ 571 | | Prefix Length | 572 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 573 | more... | 574 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 576 Figure 8 MPLS IPv6 Announcement TLV 578 5.5.1. LLEI Length 580 The LLEI Length is the same as specified in section 5.1.1. 582 5.5.2. LLEI 584 The LLEI is the same as specified in section 5.1.2. 586 5.5.3. Encaps Flags 588 The Encaps Flags are the same flags specified in section 5.2.3 590 5.5.4. MPLS Label List 592 The MPLS Label List is the same as specified in section 5.4.4 594 5.5.5. IPv6 Address 596 The IPv6 Address field holds the IPv6 address to be announced. 598 5.5.6. Prefix Length 600 The Prefix Length field indicates the number of bits in the IPv6 601 Address that represent the IPv6 prefix for the subnet (network 602 portion of the address). 604 5.5.7. MPLS IPv6 Announcement TLV usage rules 606 An LLDPDU MAY contain multiple MPLS IPv6 Announcement TLVs, however, 607 the encapsulation flags, label list, IPv6 address and prefix length 608 tuple for a specific IPv6 address MUST only appear once in the 609 LLDPDU. 611 6. Security Considerations 613 615 7. IANA Considerations 617 619 8. Conclusions 621 623 9. References 625 9.1. Normative References 627 [802.1AB] "IEEE Standard for Local and metropolitan area networks- 628 Station and Media Access Control Connectivity Discovery", 629 IEEE Std 802.1AB-2016, 29 January 2016. 631 [RFC2119] Bradner, S. "Key words for use in RFCs to Indicate 632 Requirement Levels", RFC 2119, March 1997. 634 [RFC3032] Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y., 635 Farinacci, D., Li, T. and Conta, A. "MPLS Label Stack 636 Encoding", RFC 3032, January 2001. 638 [RFC7042] Eastlake, D. and Abley, J. "IANA Considerations and IETF 639 Protocol and Documentation Usage for IEEE 802 Parameters", 640 RFC 7042, October 2013. 642 [I-D.ietf-lsvr-l3dl] Bush, R., Austein, R. and Patel, K., "Layer 3 643 Discovery and Liveness", draft-ietf-lsvr-l3dl-02.txt (work 644 in progress), July 2019. 646 9.2. Informative References 648 [802.1ABdh] "Amendment: Support for Multiframe Protocol Data Units", 649 Project P802.1ABdh, September 2019. 650 https://standards.ieee.org/project/802_1ABdh.html 652 10. Acknowledgments 654 656 This document was prepared using 2-Word-v2.0.template.dot. 658 Authors' Addresses 660 Paul Congdon 661 Tallac Networks, Inc 662 6528 Lonetree Blvd. 663 Rocklin, CA 95765 665 Email: paul.congdon@tallac.com 666 Paul Bottorff 667 Aruba a Hewlett Packard Enterprise Company 668 8000 Foothill Blvd 669 Roseville, CA 95747 671 Email: paul.bottorff@hpe.com