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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(See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Outdated reference: A later version (-38) exists of draft-ietf-lisp-rfc6830bis-28 == Outdated reference: A later version (-05) exists of draft-brockners-ippm-ioam-vxlan-gpe-03 == Outdated reference: A later version (-22) exists of draft-ietf-tsvwg-ecn-encap-guidelines-13 -- Obsolete informational reference (is this intentional?): RFC 2460 (Obsoleted by RFC 8200) Summary: 0 errors (**), 0 flaws (~~), 4 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Internet Engineering Task Force F. Maino, Ed. 3 Internet-Draft Cisco 4 Intended status: Standards Track J. Lemon 5 Expires: July 9, 2020 Broadcom 6 P. Agarwal 7 Innovium 8 D. Lewis 9 M. Smith 10 Cisco 11 January 6, 2020 13 LISP Generic Protocol Extension 14 draft-ietf-lisp-gpe-13 16 Abstract 18 This document describes extentions to the Locator/ID Separation 19 Protocol (LISP) Data-Plane, via changes to the LISP header, to 20 support multi-protocol encapsulation. 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 July 9, 2020. 39 Copyright Notice 41 Copyright (c) 2020 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 1.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 3 58 1.2. Definition of Terms . . . . . . . . . . . . . . . . . . . 3 59 2. LISP Header Without Protocol Extensions . . . . . . . . . . . 3 60 3. Generic Protocol Extension for LISP (LISP-GPE) . . . . . . . 4 61 4. Implementation and Deployment Considerations . . . . . . . . 6 62 4.1. Applicability Statement . . . . . . . . . . . . . . . . . 6 63 4.2. Congestion Control Functionality . . . . . . . . . . . . 7 64 4.3. UDP Checksum . . . . . . . . . . . . . . . . . . . . . . 7 65 4.3.1. UDP Zero Checksum Handling with IPv6 . . . . . . . . 8 66 4.4. Ethernet Encapsulated Payloads . . . . . . . . . . . . . 9 67 5. Backward Compatibility . . . . . . . . . . . . . . . . . . . 10 68 5.1. Detection of ETR Capabilities . . . . . . . . . . . . . . 10 69 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 70 6.1. LISP-GPE Next Protocol Registry . . . . . . . . . . . . . 10 71 7. Security Considerations . . . . . . . . . . . . . . . . . . . 10 72 8. Acknowledgements and Contributors . . . . . . . . . . . . . . 11 73 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 74 9.1. Normative References . . . . . . . . . . . . . . . . . . 11 75 9.2. Informative References . . . . . . . . . . . . . . . . . 12 76 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13 78 1. Introduction 80 The LISP Data-Plane is defined in [I-D.ietf-lisp-rfc6830bis]. It 81 specifies an encapsulation format that carries IPv4 or IPv6 packets 82 (henceforth jointly referred to as IP) in a LISP header and outer 83 UDP/IP transport. 85 The LISP Data-Plane header does not specify the protocol being 86 encapsulated and therefore is currently limited to encapsulating only 87 IP packet payloads. Other protocols, most notably Virtual eXtensible 88 Local Area Network (VXLAN) [RFC7348] (which defines a similar header 89 format to LISP), are used to encapsulate Layer-2 (L2) protocols such 90 as Ethernet. 92 This document defines an extension for the LISP header, as defined in 93 [I-D.ietf-lisp-rfc6830bis], to indicate the inner protocol, enabling 94 the encapsulation of Ethernet, IP or any other desired protocol all 95 the while ensuring compatibility with existing LISP deployments. 97 A flag in the LISP header, called the P-bit, is used to signal the 98 presence of the 8-bit Next Protocol field. The Next Protocol field, 99 when present, uses 8 bits of the field that was allocated to the 100 echo-noncing and map-versioning features in 101 [I-D.ietf-lisp-rfc6830bis]. Those two features are no longer 102 available when the P-bit is used. However, appropriate LISP-GPE shim 103 headers can be defined to specify capabilities that are equivalent to 104 echo-noncing and/or map-versioning. 106 Since all of the reserved bits of the LISP Data-Plane header have 107 been allocated, LISP-GPE can also be used to extend the LISP Data- 108 Plane header by defining Next Protocol "shim" headers that implements 109 new data plane functions not supported in the LISP header. For 110 example, the use of the Group-Based Policy (GBP) header 111 [I-D.lemon-vxlan-lisp-gpe-gbp] or of the In-situ Operations, 112 Administration, and Maintenance (IOAM) header 113 [I-D.brockners-ippm-ioam-vxlan-gpe] with LISP-GPE, can be considered 114 an extension to add support in the Data-Plane for Group-Based Policy 115 functionalities or IOAM metadata. 117 1.1. Conventions 119 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 120 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 121 "OPTIONAL" in this document are to be interpreted as described in BCP 122 14 [RFC2119] [RFC8174] when, and only when, they appear in all 123 capitals, as shown here. 125 1.2. Definition of Terms 127 This document uses terms already defined in 128 [I-D.ietf-lisp-rfc6830bis]. 130 2. LISP Header Without Protocol Extensions 132 As described in Section 1, the LISP header has no protocol identifier 133 that indicates the type of payload being carried. Because of this, 134 LISP is limited to carrying IP payloads. 136 The LISP header [I-D.ietf-lisp-rfc6830bis] contains a series of flags 137 (some defined, some reserved), a Nonce/Map-version field and an 138 instance ID/Locator-status-bit field. The flags provide flexibility 139 to define how the various fields are encoded. Notably, Flag bit 5 is 140 the last reserved bit in the LISP header. 142 0 1 2 3 143 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 1 144 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 145 |N|L|E|V|I|R|K|K| Nonce/Map-Version | 146 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 147 | Instance ID/Locator-Status-Bits | 148 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 150 Figure 1: LISP Header 152 3. Generic Protocol Extension for LISP (LISP-GPE) 154 This document defines two changes to the LISP header in order to 155 support multi-protocol encapsulation: the introduction of the P-bit 156 and the definition of a Next Protocol field. This document specifies 157 the protocol behavior when the P-bit is set to 1, no changes are 158 introduced when the P-bit is set to 0. The LISP-GPE header is shown 159 in Figure 2 and described below. 161 0 1 2 3 162 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 1 163 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 164 |N|L|E|V|I|P|K|K| Reserved | Next Protocol | 165 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 166 | Instance ID | 167 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 169 Figure 2: LISP-GPE Header 171 P-Bit: Flag bit 5 is defined as the Next Protocol bit. The P-bit is 172 set to 1 to indicate the presence of the 8 bit Next Protocol 173 field. 175 If the P-bit is clear (0) the LISP header is bit-by-bit equivalent 176 to the definition in [I-D.ietf-lisp-rfc6830bis]. 178 When the P-bit is set to 1, bits N, E, and V MUST be set zero on 179 transmission and ignored on receipt. Features equivalent to those 180 that were implemented with bits N,E and V in 181 [I-D.ietf-lisp-rfc6830bis], such as echo-noncing and map- 182 versioning, can be implemented by defining appropriate LISP-GPE 183 shim headers. 185 Next Protocol: The lower 8 bits of the first 32-bit word are used to 186 carry a Next Protocol. This Next Protocol field contains the 187 protocol of the encapsulated payload packet. 189 This document defines the following Next Protocol values: 191 0x01 : IPv4 193 0x02 : IPv6 195 0x03 : Ethernet 197 0x04 : Network Service Header (NSH) [RFC8300] 199 0x05 to 0x7F: Unassigned 201 0x80 to 0xFF: Unassigned (shim headers) 203 The values are tracked in the IANA LISP-GPE Next Protocol Registry 204 as described in Section 6.1. 206 Next protocol values from Ox80 to 0xFF are assigned to protocols 207 encoded as generic "shim" headers. All shim protocols MUST use the 208 header structure in Figure 3, which includes a Next Protocol field. 209 When a shim header is used with other protocols identified by next 210 protocol values from 0x0 to 0x7F, the shim header MUST come before 211 the further protocol, and the next header of the shim will indicate 212 which protocol follows the shim header. 214 Shim headers can be used to incrementally deploy new GPE features, 215 keeping the processing of shim headers known to a given xTR 216 implementation in the 'fast' path (typically an ASIC), while punting 217 the processing of the remaining new GPE features to the 'slow' path. 219 Shim protocols MUST have the first 32 bits defined as: 221 0 1 2 3 222 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 1 223 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 224 | Type | Length | Reserved | Next Protocol | 225 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 226 | | 227 ~ Protocol Specific Fields ~ 228 | | 229 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 231 Figure 3: Shim Header 233 Where: 235 Type: This field identifies the different messages of this protocol. 237 Length: The length, in 4-octect units, of this protocol message not 238 including the first 4 octects. 240 Reserved: The use of this field is reserved to the protocol defined 241 in this message. 243 Next Protocol Field: The next protocol field contains the protocol 244 of the encapsulated payload. The values are tracked in the IANA 245 LISP-GPE Next Protocol Registry as described in Section 6.1. 247 4. Implementation and Deployment Considerations 249 4.1. Applicability Statement 251 LISP-GPE conforms, as an UDP-based encapsulation protocol, to the UDP 252 usage guidelines as specified in [RFC8085]. The applicability of 253 these guidelines are dependent on the underlay IP network and the 254 nature of the encapsulated payload. 256 [RFC8085] outlines two applicability scenarios for UDP applications, 257 1) general Internet and 2) controlled environment. The controlled 258 environment means a single administrative domain or adjacent set of 259 cooperating domains. A network in a controlled environment can be 260 managed to operate under certain conditions whereas in general 261 Internet this cannot be done. Hence requirements for a tunnel 262 protocol operating under a controlled environment can be less 263 restrictive than the requirements of general internet. 265 LISP-GPE scope of applicability is the same set of use cases covered 266 by[I-D.ietf-lisp-rfc6830bis] for the LISP dataplane protocol. The 267 common property of these use cases is a large set of cooperating 268 entities seeking to communicate over the public Internet or other 269 large underlay IP infrastructures, while keeping the addressing and 270 topology of the cooperating entities separate from the underlay and 271 Internet topology, routing, and addressing. 273 LISP-GPE is meant to be deployed in network environments operated by 274 a single operator or adjacent set of cooperating network operators 275 that fits with the definition of controlled environments in 276 [RFC8085]. 278 For the purpose of this document, a traffic-managed controlled 279 environment (TMCE), outlined in [RFC8086], is defined as an IP 280 network that is traffic-engineered and/or otherwise managed (e.g., 281 via use of traffic rate limiters) to avoid congestion. Significant 282 portions of text in this Section are based on [RFC8086]. 284 It is the responsibility of the network operators to ensure that the 285 guidelines/requirements in this section are followed as applicable to 286 their LISP-GPE deployments 288 4.2. Congestion Control Functionality 290 LISP-GPE does not natively provide congestion control functionality 291 and relies on the payload protocol traffic for congestion control. 292 As such LISP-GPE MUST be used with congestion controlled traffic or 293 within a network that is traffic managed to avoid congestion (TMCE). 294 An operator of a traffic managed network (TMCE) may avoid congestion 295 by careful provisioning of their networks, rate-limiting of user data 296 traffic and traffic engineering according to path capacity. 298 Encapsulated payloads may have Explicit Congestion Notification 299 mechanisms that may or may not be mapped to the outer IP header ECN 300 field. Such new encapsulated payolads, when registered with LISP- 301 GPE, MUST be accompanied by a set of guidelines derived from 302 [I-D.ietf-tsvwg-ecn-encap-guidelines] and [RFC6040]. 304 4.3. UDP Checksum 306 For IP payloads, section 5.3 of [I-D.ietf-lisp-rfc6830bis] specifies 307 how to handle UDP Checksums encouraging implementors to consider UDP 308 checksum usage guidelines in section 3.4 of [RFC8085] when it is 309 desirable to protect UDP and LISP headers against corruption. 311 In order to provide integrity of LISP-GPE headers, options and 312 payload, for example to avoid mis-delivery of payload to different 313 tenant systems in case of data corruption, outer UDP checksum SHOULD 314 be used with LISP-GPE when transported over IPv4. The UDP checksum 315 provides a statistical guarantee that a payload was not corrupted in 316 transit. These integrity checks are not strong from a coding or 317 cryptographic perspective and are not designed to detect physical- 318 layer errors or malicious modification of the datagram (see 319 Section 3.4 of [RFC8085]). In deployments where such a risk exists, 320 an operator SHOULD use additional data integrity mechanisms such as 321 offered by IPSec. 323 An operator MAY choose to disable UDP checksum and use zero checksum 324 if LISP-GPE packet integrity is provided by other data integrity 325 mechanisms such as IPsec or additional checksums or if one of the 326 conditions in Section 4.3.1 a, b, c are met. 328 By default, UDP checksum MUST be used when LISP-GPE is transported 329 over IPv6. A tunnel endpoint MAY be configured for use with zero UDP 330 checksum if additional requirements in Section 4.3.1 are met. 332 4.3.1. UDP Zero Checksum Handling with IPv6 334 When LISP-GPE is used over IPv6, UDP checksum is used to protect IPv6 335 headers, UDP headers and LISP-GPE headers and payload from potential 336 data corruption. As such by default LISP-GPE MUST use UDP checksum 337 when transported over IPv6. An operator MAY choose to configure to 338 operate with zero UDP checksum if operating in a traffic managed 339 controlled environment as stated in Section 4.1 if one of the 340 following conditions are met: 342 a. It is known that the packet corruption is exceptionally unlikely 343 (perhaps based on knowledge of equipment types in their underlay 344 network) and the operator is willing to take a risk of undetected 345 packet corruption 347 b. It is judged through observational measurements (perhaps through 348 historic or current traffic flows that use non zero checksum) 349 that the level of packet corruption is tolerably low and where 350 the operator is willing to take the risk of undetected corruption 352 c. LISP-GPE payload is carrying applications that are tolerant of 353 misdelivered or corrupted packets (perhaps through higher layer 354 checksum validation and/or reliability through retransmission) 356 In addition LISP-GPE tunnel implementations using Zero UDP checksum 357 MUST meet the following requirements: 359 1. Use of UDP checksum over IPv6 MUST be the default configuration 360 for all LISP-GPE tunnels 362 2. If LISP-GPE is used with zero UDP checksum over IPv6 then such 363 xTR implementation MUST meet all the requirements specified in 364 section 4 of [RFC6936] and requirements 1 as specified in section 365 5 of [RFC6936] 367 3. The ETR that decapsulates the packet SHOULD check the source and 368 destination IPv6 addresses are valid for the LISP-GPE tunnel that 369 is configured to receive Zero UDP checksum and discard other 370 packets for which such check fails 372 4. The ITR that encapsulates the packet MAY use different IPv6 373 source addresses for each LISP-GPE tunnel that uses Zero UDP 374 checksum mode in order to strengthen the decapsulator's check of 375 the IPv6 source address (i.e the same IPv6 source address is not 376 to be used with more than one IPv6 destination address, 377 irrespective of whether that destination address is a unicast or 378 multicast address). When this is not possible, it is RECOMMENDED 379 to use each source address for as few LISP-GPE tunnels that use 380 zero UDP checksum as is feasible 382 5. Measures SHOULD be taken to prevent LISP-GPE traffic over IPv6 383 with zero UDP checksum from escaping into the general Internet. 384 Examples of such measures include employing packet filters at the 385 PETR and/or keeping logical or physical separation of LISP 386 network from networks carrying General Internet 388 The above requirements do not change either the requirements 389 specified in [RFC2460] as modified by [RFC6935] or the requirements 390 specified in [RFC6936]. 392 The requirement to check the source IPv6 address in addition to the 393 destination IPv6 address, plus the recommendation against reuse of 394 source IPv6 addresses among LISP-GPE tunnels collectively provide 395 some mitigation for the absence of UDP checksum coverage of the IPv6 396 header. A traffic-managed controlled environment that satisfies at 397 least one of three conditions listed at the beginning of this section 398 provides additional assurance. 400 4.4. Ethernet Encapsulated Payloads 402 When a LISP-GPE router performs Ethernet encapsulation, the inner 403 802.1Q [IEEE.802.1Q_2014] 3-bit priority code point (PCP) field MAY 404 be mapped from the encapsulated frame to the 3-bit Type of Service 405 field in the outer IPv4 header, or in the case of IPv6 the 'Traffic 406 Class' field. 408 When a LISP-GPE router performs Ethernet encapsulation, the inner 409 header 802.1Q [IEEE.802.1Q_2014] VLAN Identifier (VID) MAY be mapped 410 to, or used to determine the LISP Instance IDentifier (IID) field. 412 5. Backward Compatibility 414 LISP-GPE uses the same UDP destination port (4341) allocated to LISP. 416 When encapsulating IP packets to a non LISP-GPE capable router the 417 P-bit MUST be set to 0. That is, the encapsulation format defined in 418 this document MUST NOT be sent to a router that has not indicated 419 that it supports this specification because such a router would 420 ignore the P-bit (as described in [I-D.ietf-lisp-rfc6830bis]) and so 421 would misinterpret the other LISP header fields possibly causing 422 significant errors. 424 5.1. Detection of ETR Capabilities 426 The discovery of xTR capabilities to support LISP-GPE is out of the 427 scope of this document. Given that the applicability domain of LISP- 428 GPE is a traffic-managed controlled environment, ITR/ETR (xTR) 429 configuration mechanisms may be used for this purpose. 431 6. IANA Considerations 433 6.1. LISP-GPE Next Protocol Registry 435 IANA is requested to set up a registry of LISP-GPE "Next Protocol". 436 These are 8-bit values. Next Protocol values in the table below are 437 defined in this document. New values are assigned under the 438 Specification Required policy [RFC8126]. The protocols that are 439 being assigned values do not themselves need to be IETF standards 440 track protocols. 442 +---------------+-------------+---------------+ 443 | Next Protocol | Description | Reference | 444 +---------------+-------------+---------------+ 445 | 0x00 | Reserved | This Document | 446 | 0x01 | IPv4 | This Document | 447 | 0x02 | IPv6 | This Document | 448 | 0x03 | Ethernet | This Document | 449 | 0x04 | NSH | This Document | 450 | 0x05..0x7F | Unassigned | | 451 | 0x82..0xFF | Unassigned | | 452 +---------------+-------------+---------------+ 454 7. Security Considerations 456 LISP-GPE security considerations are similar to the LISP security 457 considerations and mitigation techniques documented in [RFC7835]. 459 LISP-GPE, as many encapsulations that use optional extensions, is 460 subject to on-path adversaries that by manipulating the P-Bit and the 461 packet itself can remove part of the payload or claim to encapsulate 462 any protocol payload type. Typical integrity protection mechanisms 463 (such as IPsec) SHOULD be used in combination with LISP-GPE by those 464 protocol extensions that want to protect from on-path attackers. 466 With LISP-GPE, issues such as data-plane spoofing, flooding, and 467 traffic redirection may depend on the particular protocol payload 468 encapsulated. 470 8. Acknowledgements and Contributors 472 A special thank you goes to Dino Farinacci for his guidance and 473 detailed review. 475 This Working Group (WG) document originated as draft-lewis-lisp-gpe; 476 the following are its coauthors and contributors along with their 477 respective affiliations at the time of WG adoption. The editor of 478 this document would like to thank and recognize them and their 479 contributions. These coauthors and contributors provided invaluable 480 concepts and content for this document's creation. 482 o Darrel Lewis, Cisco Systems, Inc. 484 o Fabio Maino, Cisco Systems, Inc. 486 o Paul Quinn, Cisco Systems, Inc. 488 o Michael Smith, Cisco Systems, Inc. 490 o Navindra Yadav, Cisco Systems, Inc. 492 o Larry Kreeger 494 o John Lemon, Broadcom 496 o Puneet Agarwal, Innovium 498 9. References 500 9.1. Normative References 502 [I-D.ietf-lisp-rfc6830bis] 503 Farinacci, D., Fuller, V., Meyer, D., Lewis, D., and A. 504 Cabellos-Aparicio, "The Locator/ID Separation Protocol 505 (LISP)", draft-ietf-lisp-rfc6830bis-28 (work in progress), 506 November 2019. 508 [IEEE.802.1Q_2014] 509 IEEE, "IEEE Standard for Local and metropolitan area 510 networks--Bridges and Bridged Networks", IEEE 802.1Q-2014, 511 DOI 10.1109/ieeestd.2014.6991462, December 2014, 512 . 515 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 516 Requirement Levels", BCP 14, RFC 2119, 517 DOI 10.17487/RFC2119, March 1997, 518 . 520 [RFC6040] Briscoe, B., "Tunnelling of Explicit Congestion 521 Notification", RFC 6040, DOI 10.17487/RFC6040, November 522 2010, . 524 9.2. Informative References 526 [I-D.brockners-ippm-ioam-vxlan-gpe] 527 Brockners, F., Bhandari, S., Govindan, V., Pignataro, C., 528 Gredler, H., Leddy, J., Youell, S., Mizrahi, T., Kfir, A., 529 Gafni, B., Lapukhov, P., and M. Spiegel, "VXLAN-GPE 530 Encapsulation for In-situ OAM Data", draft-brockners-ippm- 531 ioam-vxlan-gpe-03 (work in progress), November 2019. 533 [I-D.ietf-tsvwg-ecn-encap-guidelines] 534 Briscoe, B., Kaippallimalil, J., and P. Thaler, 535 "Guidelines for Adding Congestion Notification to 536 Protocols that Encapsulate IP", draft-ietf-tsvwg-ecn- 537 encap-guidelines-13 (work in progress), May 2019. 539 [I-D.lemon-vxlan-lisp-gpe-gbp] 540 Lemon, J., Maino, F., Smith, M., and A. Isaac, "Group 541 Policy Encoding with VXLAN-GPE and LISP-GPE", draft-lemon- 542 vxlan-lisp-gpe-gbp-02 (work in progress), April 2019. 544 [RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6 545 (IPv6) Specification", RFC 2460, DOI 10.17487/RFC2460, 546 December 1998, . 548 [RFC6935] Eubanks, M., Chimento, P., and M. Westerlund, "IPv6 and 549 UDP Checksums for Tunneled Packets", RFC 6935, 550 DOI 10.17487/RFC6935, April 2013, 551 . 553 [RFC6936] Fairhurst, G. and M. Westerlund, "Applicability Statement 554 for the Use of IPv6 UDP Datagrams with Zero Checksums", 555 RFC 6936, DOI 10.17487/RFC6936, April 2013, 556 . 558 [RFC7348] Mahalingam, M., Dutt, D., Duda, K., Agarwal, P., Kreeger, 559 L., Sridhar, T., Bursell, M., and C. Wright, "Virtual 560 eXtensible Local Area Network (VXLAN): A Framework for 561 Overlaying Virtualized Layer 2 Networks over Layer 3 562 Networks", RFC 7348, DOI 10.17487/RFC7348, August 2014, 563 . 565 [RFC7835] Saucez, D., Iannone, L., and O. Bonaventure, "Locator/ID 566 Separation Protocol (LISP) Threat Analysis", RFC 7835, 567 DOI 10.17487/RFC7835, April 2016, 568 . 570 [RFC8085] Eggert, L., Fairhurst, G., and G. Shepherd, "UDP Usage 571 Guidelines", BCP 145, RFC 8085, DOI 10.17487/RFC8085, 572 March 2017, . 574 [RFC8086] Yong, L., Ed., Crabbe, E., Xu, X., and T. Herbert, "GRE- 575 in-UDP Encapsulation", RFC 8086, DOI 10.17487/RFC8086, 576 March 2017, . 578 [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for 579 Writing an IANA Considerations Section in RFCs", BCP 26, 580 RFC 8126, DOI 10.17487/RFC8126, June 2017, 581 . 583 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 584 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 585 May 2017, . 587 [RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed., 588 "Network Service Header (NSH)", RFC 8300, 589 DOI 10.17487/RFC8300, January 2018, 590 . 592 Authors' Addresses 594 Fabio Maino (editor) 595 Cisco Systems 596 San Jose, CA 95134 597 USA 599 Email: fmaino@cisco.com 600 Jennifer Lemon 601 Broadcom 602 270 Innovation Drive 603 San Jose, CA 95134 604 USA 606 Email: jennifer.lemon@broadcom.com 608 Puneet Agarwal 609 Innovium 610 USA 612 Email: puneet@acm.org 614 Darrel Lewis 615 Cisco Systems 617 Email: darlewis@cisco.com 619 Michael Smith 620 Cisco Systems 622 Email: michsmit@cisco.com