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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) No issues found here. Summary: 0 errors (**), 0 flaws (~~), 1 warning (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 MPLS Working Group R. Gandhi 3 Internet-Draft P. Brissette 4 Intended status: Standards Track Cisco Systems, Inc. 5 Expires: January 13, 2022 E. Leyton 6 Verizon Wireless 7 July 12, 2021 9 Encapsulation of Simple TWAMP (STAMP) for Pseudowires in MPLS Networks 10 draft-gandhi-mpls-stamp-pw-00 12 Abstract 14 Pseudowires (PWs) are used in MPLS networks for various services 15 including carrying layer 2 and layer 3 data packets. This document 16 describes the procedure for encapsulation of the Simple Two-Way 17 Active Measurement Protocol (STAMP) defined in RFC 8762 and its 18 optional extensions defined in RFC 8972 for PWs in MPLS networks. 19 The procedure uses PW Generic Associated Channel (G-ACh) to 20 encapsulate the STAMP test packets with or without an IP/UDP header. 22 Status of This Memo 24 This Internet-Draft is submitted in full conformance with the 25 provisions of BCP 78 and BCP 79. 27 Internet-Drafts are working documents of the Internet Engineering 28 Task Force (IETF). Note that other groups may also distribute 29 working documents as Internet-Drafts. The list of current Internet- 30 Drafts is at https://datatracker.ietf.org/drafts/current/. 32 Internet-Drafts are draft documents valid for a maximum of six months 33 and may be updated, replaced, or obsoleted by other documents at any 34 time. It is inappropriate to use Internet-Drafts as reference 35 material or to cite them other than as "work in progress." 37 This Internet-Draft will expire on January 13, 2022. 39 Copyright Notice 41 Copyright (c) 2021 IETF Trust and the persons identified as the 42 document authors. All rights reserved. 44 This document is subject to BCP 78 and the IETF Trust's Legal 45 Provisions Relating to IETF Documents 46 (https://trustee.ietf.org/license-info) in effect on the date of 47 publication of this document. Please review these documents 48 carefully, as they describe your rights and restrictions with respect 49 to this document. Code Components extracted from this document must 50 include Simplified BSD License text as described in Section 4.e of 51 the Trust Legal Provisions and are provided without warranty as 52 described in the Simplified BSD License. 54 Table of Contents 56 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 57 2. Conventions Used in This Document . . . . . . . . . . . . . . 3 58 2.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 59 2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 3 60 2.3. Reference Topology . . . . . . . . . . . . . . . . . . . 4 61 3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 4 62 4. Session-Sender Test Packet . . . . . . . . . . . . . . . . . 5 63 4.1. Session-Sender Test Packet with IP/UDP Header . . . . . . 5 64 4.2. Session-Sender Test Packet without IP/UDP Header . . . . 7 65 5. Session-Reflector Test Packet . . . . . . . . . . . . . . . . 7 66 5.1. Session-Reflector Test Packet with IP/UDP Header . . . . 8 67 5.2. Session-Reflector Test Packet without IP/UDP Header . . . 10 68 6. Security Considerations . . . . . . . . . . . . . . . . . . . 11 69 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 70 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 71 8.1. Normative References . . . . . . . . . . . . . . . . . . 12 72 8.2. Informative References . . . . . . . . . . . . . . . . . 12 73 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 13 74 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13 76 1. Introduction 78 The Simple Two-way Active Measurement Protocol (STAMP) provides 79 capabilities for the measurement of various metrics in IP networks 80 [RFC8762] without the use of a control channel to pre-signal session 81 parameters. [RFC8972] defines optional extensions for STAMP. 83 Pseudowires (PWs) are used in MPLS networks for various services 84 including carrying layer 2 and layer 3 data packets [RFC6658]. The 85 PWs are bidirectional in nature. The PWs can be point-to-point or 86 point-to-multipoint. A PW Generic Associated Channel (G-ACh) 87 [RFC5586] provides a mechanism to transport Operations, 88 Administration, and Maintenance (OAM) and other control messages over 89 MPLS data plane. The G-ACh channel types identify the various OAM 90 messages being transported over the channel. 92 The STAMP test packets need to be transmitted with the same MPLS 93 label stack that is used by the PW traffic to ensure proper 94 validation of underlay path taken by the actual PW traffic. Also, 95 the test packets need to follow the same ECMP path taken by the PW 96 traffic. The STAMP test packets may be encapsulated over the PW 97 associated channel with or without an IP/UDP header. The 98 requirements for the encapsulation of the STAMP test packets for the 99 PWs in MPLS networks can be summarized as follows: 101 o The PW associated channel MUST support STAMP test packets with IP/ 102 UDP header. 104 o The PW associated channel MUST support STAMP test packets without 105 IP/UDP header. 107 o The Session-Sender test packets MUST follow the same underlay path 108 taken by the traffic for the associated PW channel. 110 o The Session-Sender test packets MUST follow the same ECMP underlay 111 path taken by the traffic for the associated PW channel. 113 o The Session-Reflector test packets MAY follow the same reverse 114 underlay path taken by Session-Sender test packets. 116 o The Session-Reflector test packets MAY follow the same reverse ECMP 117 underlay path taken by Session-Sender test packets. 119 This document describes the procedure for encapsulation of the STAMP 120 defined in [RFC8762] and its optional extensions defined in [RFC8972] 121 for point-to-point PWs in MPLS networks. The procedure uses PW 122 Generic Associated Channel (G-ACh) to encapsulate the STAMP test 123 packets with or without an IP/UDP header. The procedure for point- 124 to-multipoint PWs will be added in future. 126 2. Conventions Used in This Document 128 2.1. Requirements Language 130 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 131 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 132 document are to be interpreted as described in [RFC2119] [RFC8174] 133 when, and only when, they appear in all capitals, as shown here. 135 2.2. Abbreviations 137 ECMP: Equal Cost Multi-Path. 139 G-ACh: Generic Associated Channel. 141 GAL: G-ACh Label. 143 HMAC: Hashed Message Authentication Code. 145 MPLS: Multiprotocol Label Switching. 147 OAM: Operations, Administration, and Maintenance. 149 PW: Pseudowires. 151 SHA: Secure Hash Algorithm. 153 STAMP: Simple Two-way Active Measurement Protocol. 155 TC: Traffic Class. 157 2.3. Reference Topology 159 In the Reference Topology shown in Figure 1, there exists a packet 160 pseudowire to transport data between LSRs S1 and R1. The STAMP 161 Session-Sender on LSR S1 initiates a Session-Sender test packet and 162 the STAMP Session-Reflector on LSR R1 transmits a reply test packet. 163 The reply test packet is transmitted to the STAMP Session-Sender on 164 the same path (same set of links and nodes) in the reverse direction 165 of the path taken towards the Session-Reflector. 167 |<-------- Pseudowire ------->| 168 | | 169 | T1 T2 | 170 | / \ | 171 +-------+ Test Packet +-------+ 172 | | - - - - - - - - - ->| | 173 | S1 |=====================| R1 | 174 | |<- - - - - - - - - - | | 175 +-------+ Reply Test Packet +-------+ 176 \ / 177 T4 T3 179 STAMP Session-Sender STAMP Session-Reflector 181 T1, T2, T3, T4: Timestamps as described in [RFC8762] 183 Figure 1: Reference Topology 185 3. Overview 187 The STAMP Session-Sender and Session-Reflector test packets defined 188 in [RFC8972] are transmitted over the PWs in MPLS networks. The base 189 STAMP test packets can be encapsulated using IP/UDP header and may 190 use Destination UDP port 862 [RFC8762]. 192 The STAMP test packets are encapsulated with MPLS header using the 193 same label stack as the PW traffic and the PW G-ACh header. The 194 encapsulation allows the STAMP test packets to follow the same path 195 as the PW traffic, and provide the same ECMP path selection on the 196 intermediate nodes. 198 There are two ways in which STAMP test packets may be encapsulated 199 over a PW associated channel, either using an IP/UDP header or 200 without using an IP/UDP header. 202 For encapsulating the STAMP test packets over a PW associated channel 203 with an IP/UDP header, IPv4 and IPv6 G-ACh types [RFC4385] are used 204 for both Session-Sender and Session-Reflector test packets. The 205 destination UDP port numbers in the Session-Sender and Session- 206 Reflector test packets discriminate the test packets. The IP version 207 (IPv4 or IPv6) MUST match the IP version used for signaling for 208 dynamically established PWs or MUST be configured for statically 209 provisioned PWs. 211 For encapsulating the STAMP test packets over a PW associated channel 212 without an IP/UDP header, two new G-ACh types are defined in this 213 document, one for the Session-Sender test packets and one for the 214 Session-Reflector test packets. The different G-ACh types are 215 required for the Session-Sender and Session-Reflector test packets as 216 the STAMP test packet formats do not have a way to discriminate them. 218 The Time to Live (TTL)/Hop Limit (HL) and Generalized TTL Security 219 Mechanism (GTSM) procedures from [RFC5082] apply to this 220 encapsulation, and hence the TTL/HL is set to 255. 222 The G-ACh label (GAL) [RFC5586] is not added in the MPLS label stack. 224 4. Session-Sender Test Packet 226 4.1. Session-Sender Test Packet with IP/UDP Header 228 The content of an example STAMP Session-Sender test packet 229 encapsulated over a PW associated channel using an IP/UDP header is 230 shown in Figure 2. The STAMP G-ACh header [RFC5586] with G-ACh MUST 231 immediately follow the bottom of the MPLS label stack. The payload 232 contains the STAMP Session-Sender test packet defined in [RFC8972]. 234 0 1 2 3 235 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 1 236 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 237 | Label(1) | TC |S| TTL | 238 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 239 . . 240 . . 241 . . 242 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 243 | PW Label | TC |1| TTL | 244 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 245 |0 0 0 1|Version| Reserved | IPv4 (0x0021) or IPv6 (0x0057)| 246 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 247 | IP Header | 248 . Source IP Address = Session-Sender IPv4 or IPv6 Address . 249 . Destination IP Address=Session-Reflector IPv4 or IPv6 Address. 250 . . 251 +---------------------------------------------------------------+ 252 | UDP Header | 253 . Source Port = As chosen by Session-Sender . 254 . Destination Port = User-configured Destination Port | 862 . 255 . . 256 +---------------------------------------------------------------+ 257 | Payload = Test Packet as specified in Section 3 of RFC 8972 | 258 . in Figure 1 and Figure 3 . 259 . . 260 +---------------------------------------------------------------+ 261 | Optional STAMP TLVs defined in RFC 8972 | 262 . . 263 +---------------------------------------------------------------+ 265 Figure 2: Example Session-Sender Test Packet with IP/UDP Header 267 The STAMP Session-Sender test packet G-ACh header contains following 268 fields: 270 Version: The Version field is set to 0, as defined in [RFC4385]. 272 Reserved: Reserved Bits MUST be set to zero upon transmission and 273 ignored upon receipt. 275 Channel Type: G-ACh channel type for IPv4 header (0x0021) or IPv6 276 header (0x0057) [RFC4385]. 278 4.2. Session-Sender Test Packet without IP/UDP Header 280 The content of an example STAMP Session-Sender test packet 281 encapsulated over a PW associated channel without using an IP/UDP 282 header is shown in Figure 3. The STAMP G-ACh header [RFC5586] with 283 new STAMP Session-Sender G-ACh type (value TBD1) MUST immediately 284 follow the bottom of the MPLS label stack. The payload contains the 285 STAMP Session-Sender test packet defined in [RFC8972]. 287 0 1 2 3 288 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 1 289 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 290 | Label(1) | TC |S| TTL | 291 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 292 . . 293 . . 294 . . 295 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 296 | PW Label | TC |1| TTL | 297 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 298 |0 0 0 1|Version| Reserved | STAMP G-ACh (TBD1) | 299 +---------------------------------------------------------------+ 300 | Payload = Test Packet as specified in Section 3 of RFC 8972 | 301 . in Figure 1 and Figure 3 . 302 . . 303 +---------------------------------------------------------------+ 304 | Optional STAMP TLVs defined in RFC 8972 | 305 . . 306 +---------------------------------------------------------------+ 308 Figure 3: Example Session-Sender Test Packet without IP/UDP Header 310 The STAMP Session-Sender test packet G-ACh header contains following 311 fields: 313 Version: The Version field is set to 0, as defined in [RFC4385]. 315 Reserved: Reserved Bits MUST be set to zero upon transmission and 316 ignored upon receipt. 318 Channel Type: G-ACh channel type for STAMP Session-Sender packet 319 (TBD1). 321 5. Session-Reflector Test Packet 323 The STAMP Session-Reflector reply test packet is sent on the same 324 path in the reverse direction of a bidirectional PW. The STAMP test 325 packet can be sent using an MPLS header with or without IP/UDP 326 header. The Session-Reflector test packet is sent with an IP/UDP 327 header if the Session-Sender test packet is received with an IP/UDP 328 header, otherwise, it is sent without an IP/UDP header. 330 5.1. Session-Reflector Test Packet with IP/UDP Header 332 The content of an example STAMP Session-Reflector test packet 333 encapsulated over a PW associated channel using an IP/UDP header is 334 shown in Figure 4. The STAMP G-ACh header [RFC5586] with G-ACh MUST 335 immediately follow the bottom of the MPLS label stack. The payload 336 contains the STAMP Session-Reflector test packet defined in 337 [RFC8972]. 339 The STAMP Session-Reflector reply test packet MUST use the IP/UDP 340 information from the received test packet when an IP/UDP header is 341 present in the received test packet. 343 0 1 2 3 344 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 1 345 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 346 | Label(1) | TC |S| TTL | 347 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 348 . . 349 . . 350 . . 351 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 352 | PW Label | TC |1| TTL | 353 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 354 |0 0 0 1|Version| Reserved | IPv4 (0x0021) or IPv6 (0x0057)| 355 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 356 | IP Header | 357 . Source IP Address = Session-Reflector IPv4 or IPv6 Address . 358 . Destination IP Address . 359 . = Source IP Address from Received Test Packet . 360 . . 361 +---------------------------------------------------------------+ 362 | UDP Header | 363 . Source Port = As chosen by Session-Reflector . 364 . Destination Port = Source Port from Received Test Packet . 365 . . 366 +---------------------------------------------------------------+ 367 | Payload = Test Packet as specified in Section 3 of RFC 8972 | 368 . in Figure 2 and Figure 4 . 369 . . 370 +---------------------------------------------------------------+ 371 | Optional STAMP TLVs defined in RFC 8972 | 372 . . 373 +---------------------------------------------------------------+ 375 Figure 4: Example Session-Reflector Test Packet with IP/UDP Header 377 The STAMP Session-Reflector test packet G-ACh header contains 378 following fields: 380 Version: The Version field is set to 0, as defined in [RFC4385]. 382 Reserved: Reserved Bits MUST be set to zero upon transmission and 383 ignored upon receipt. 385 Channel Type: G-ACh channel type for IPv4 header (0x0021) or IPv6 386 header (0x0057) [RFC4385]. 388 5.2. Session-Reflector Test Packet without IP/UDP Header 390 The content of an example STAMP Session-Reflector test packet 391 encapsulated over a PW associated channel without using an IP/UDP 392 header is shown in Figure 5. The STAMP G-ACh header [RFC5586] with 393 new STAMP Session-Reflector G-ACh type (value TBD2) MUST immediately 394 follow the bottom of the MPLS label stack. The payload contains the 395 STAMP Session-Reflector test packet defined in [RFC8972]. 397 The STAMP Session-Reflector reflects the test packet back to the 398 Session-Sender using the same channel of the reverse direction of the 399 PW on which it was received. The Session-Reflector has enough 400 information to reflect the test packet received by it to the Session- 401 Sender using the PW context. 403 0 1 2 3 404 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 1 405 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 406 | Label(1) | TC |S| TTL | 407 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 408 . . 409 . . 410 . . 411 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 412 | PW Label | TC |1| TTL | 413 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 414 |0 0 0 1|Version| Reserved | STAMP G-ACh (TBD2) | 415 +---------------------------------------------------------------+ 416 | Payload = Test Packet as specified in Section 3 of RFC 8972 | 417 . in Figure 2 and Figure 4 . 418 . . 419 +---------------------------------------------------------------+ 421 Figure 5: Example Session-Reflector Test Packet without IP/UDP Header 423 The STAMP Session-Reflector test packet G-ACh header contains 424 following fields: 426 Version: The Version field is set to 0, as defined in [RFC4385]. 428 Reserved: Reserved Bits MUST be set to zero upon transmission and 429 ignored upon receipt. 431 Channel Type: G-ACh channel type for STAMP Session-Reflector packet 432 (TBD2). 434 6. Security Considerations 436 The usage of STAMP protocol is intended for deployment in limited 437 domains [RFC8799]. As such, it assumes that a node involved in STAMP 438 protocol operation has previously verified the integrity of the path 439 and the identity of the far-end STAMP Session-Reflector. 441 If desired, attacks can be mitigated by performing basic validation 442 and sanity checks, at the STAMP Session-Sender, of the counter or 443 timestamp fields in received reply test packets. The minimal state 444 associated with these protocols also limits the extent of disruption 445 that can be caused by a corrupt or invalid packet to a single test 446 cycle. 448 Use of HMAC-SHA-256 in the authenticated mode protects the data 449 integrity of the test packets. Cryptographic measures may be 450 enhanced by the correct configuration of access-control lists and 451 firewalls. 453 The security considerations specified in [RFC8762] and [RFC8972] also 454 apply to the procedure described in this document. Specifically, the 455 message integrity protection using HMAC, as defined in [RFC8762] 456 Section 4.4, also apply to the procedure described in this document. 458 Routers that support G-ACh are subject to the same security 459 considerations as defined in [RFC4385] and [RFC5586]. 461 7. IANA Considerations 463 IANA maintains G-ACh Type Registry (see 464 ). IANA is requested to allocate values for the 466 STAMP G-ACh Types from "MPLS Generalized Associated Channel (G-ACh) 467 Types (including Pseudowire Associated Channel Types)" registry. 469 +-------+------------------------------------+---------------+ 470 | Value | Description | Reference | 471 +-------+------------------------------------+---------------+ 472 | TBD1 | STAMP Session-Sender G-ACh Type | This document | 473 | TBD2 | STAMP Session-Reflector G-ACh Type | This document | 474 +-------+------------------------------------+---------------+ 476 Table 1: STAMP G-ACh Type 478 8. References 480 8.1. Normative References 482 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 483 Requirement Levels", BCP 14, RFC 2119, 484 DOI 10.17487/RFC2119, March 1997, 485 . 487 [RFC4385] Bryant, S., Swallow, G., Martini, L., and D. McPherson, 488 "Pseudowire Emulation Edge-to-Edge (PWE3) Control Word for 489 Use over an MPLS PSN", RFC 4385, DOI 10.17487/RFC4385, 490 February 2006, . 492 [RFC5586] Bocci, M., Ed., Vigoureux, M., Ed., and S. Bryant, Ed., 493 "MPLS Generic Associated Channel", RFC 5586, 494 DOI 10.17487/RFC5586, June 2009, 495 . 497 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 498 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 499 May 2017, . 501 [RFC8762] Mirsky, G., Jun, G., Nydell, H., and R. Foote, "Simple 502 Two-Way Active Measurement Protocol", RFC 8762, 503 DOI 10.17487/RFC8762, March 2020, 504 . 506 [RFC8972] Mirsky, G., Min, X., Nydell, H., Foote, R., Masputra, A., 507 and E. Ruffini, "Simple Two-Way Active Measurement 508 Protocol Optional Extensions", RFC 8972, 509 DOI 10.17487/RFC8972, January 2021, 510 . 512 8.2. Informative References 514 [RFC5082] Gill, V., Heasley, J., Meyer, D., Savola, P., Ed., and C. 515 Pignataro, "The Generalized TTL Security Mechanism 516 (GTSM)", RFC 5082, DOI 10.17487/RFC5082, October 2007, 517 . 519 [RFC6658] Bryant, S., Ed., Martini, L., Swallow, G., and A. Malis, 520 "Packet Pseudowire Encapsulation over an MPLS PSN", 521 RFC 6658, DOI 10.17487/RFC6658, July 2012, 522 . 524 [RFC8799] Carpenter, B. and B. Liu, "Limited Domains and Internet 525 Protocols", RFC 8799, DOI 10.17487/RFC8799, July 2020, 526 . 528 Acknowledgments 530 TBA. 532 Authors' Addresses 534 Rakesh Gandhi 535 Cisco Systems, Inc. 536 Canada 538 Email: rgandhi@cisco.com 540 Patrice Brissette 541 Cisco Systems, Inc. 542 Canada 544 Email: pbrisset@cisco.com 546 Edward Leyton 547 Verizon Wireless 549 Email: edward.leyton@verizonwireless.com