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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(See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Outdated reference: A later version (-16) exists of draft-ietf-bfd-vxlan-07 ** Downref: Normative reference to an Informational draft: draft-ietf-bfd-vxlan (ref. 'I-D.ietf-bfd-vxlan') == Outdated reference: A later version (-16) exists of draft-ietf-nvo3-geneve-14 ** Downref: Normative reference to an Informational RFC: RFC 7348 ** Downref: Normative reference to an Informational RFC: RFC 7365 ** Downref: Normative reference to an Informational RFC: RFC 8014 Summary: 4 errors (**), 0 flaws (~~), 3 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 NVO3 Working Group X. Min 3 Internet-Draft G. Mirsky 4 Intended status: Standards Track ZTE Corp. 5 Expires: April 24, 2020 S. Pallagatti 6 VMware 7 October 22, 2019 9 BFD for Geneve 10 draft-xiao-nvo3-bfd-geneve-01 12 Abstract 14 This document describes the use of the Bidirectional Forwarding 15 Detection (BFD) protocol in point-to-point Generic Network 16 Virtualization Encapsulation (Geneve) tunnels forming up an overlay 17 network. 19 Status of This Memo 21 This Internet-Draft is submitted in full conformance with the 22 provisions of BCP 78 and BCP 79. 24 Internet-Drafts are working documents of the Internet Engineering 25 Task Force (IETF). Note that other groups may also distribute 26 working documents as Internet-Drafts. The list of current Internet- 27 Drafts is at https://datatracker.ietf.org/drafts/current/. 29 Internet-Drafts are draft documents valid for a maximum of six months 30 and may be updated, replaced, or obsoleted by other documents at any 31 time. It is inappropriate to use Internet-Drafts as reference 32 material or to cite them other than as "work in progress." 34 This Internet-Draft will expire on April 24, 2020. 36 Copyright Notice 38 Copyright (c) 2019 IETF Trust and the persons identified as the 39 document authors. All rights reserved. 41 This document is subject to BCP 78 and the IETF Trust's Legal 42 Provisions Relating to IETF Documents 43 (https://trustee.ietf.org/license-info) in effect on the date of 44 publication of this document. Please review these documents 45 carefully, as they describe your rights and restrictions with respect 46 to this document. Code Components extracted from this document must 47 include Simplified BSD License text as described in Section 4.e of 48 the Trust Legal Provisions and are provided without warranty as 49 described in the Simplified BSD License. 51 Table of Contents 53 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 54 2. Conventions Used in This Document . . . . . . . . . . . . . . 3 55 2.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 56 2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3 57 3. BFD Packet Transmission over Geneve Tunnel . . . . . . . . . 3 58 3.1. BFD Encapsulation With Inner Ethernet/IP/UDP Header . . . 3 59 3.2. BFD Encapsulation With Inner IP/UDP Header . . . . . . . 6 60 3.3. BFD Encapsulation With Inner MPLS Header . . . . . . . . 8 61 4. Reception of BFD packet from Geneve Tunnel . . . . . . . . . 10 62 4.1. Demultiplexing of the BFD packet . . . . . . . . . . . . 11 63 5. Security Considerations . . . . . . . . . . . . . . . . . . . 11 64 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 65 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12 66 8. Normative References . . . . . . . . . . . . . . . . . . . . 12 67 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13 69 1. Introduction 71 "Generic Network Virtualization Encapsulation" (Geneve) 72 [I-D.ietf-nvo3-geneve] provides an encapsulation scheme that allows 73 building an overlay network by decoupling the address space of the 74 attached virtual hosts from that of the network. 76 This document describes the use of Bidirectional Forwarding Detection 77 (BFD) protocol [RFC5880] to enable monitoring continuity of the path 78 between two Geneve tunnel endpoints, which may be NVE (Network 79 Virtualization Edge) or other device acting as a Geneve tunnel 80 endpoint. For simplicity, in this document, NVE is used to represent 81 Geneve tunnel endpoint, TS (Tenant System) is used to represent the 82 physical or virtual device attached to a Geneve tunnel endpoint from 83 the outside. VAP (Virtual Access Point) is the NVE side of the 84 interface between the NVE and the TS, and a VAP is a logical network 85 port (virtual or physical) into a specific virtual network. For 86 detailed definitions and descriptions of NVE, TS and VAP, please 87 refer to [RFC7365] and [RFC8014]. 89 The use cases and the deployment of BFD for Geneve are consistent 90 with what's described in Section 1 and Section 3 of 91 [I-D.ietf-bfd-vxlan]. The major difference between Geneve and 92 "Virtual eXtensible Local Area Network" (VXLAN) [RFC7348] 93 encapsulation is that Geneve supports multi-protocol payload and 94 variable length options. 96 2. Conventions Used in This Document 98 2.1. Terminology 100 BFD: Bidirectional Forwarding Detection 102 CC: Continuity Check 104 GAL: Generic Associated Channel Label 106 G-ACh: Generic Associated Channel 108 Geneve: Generic Network Virtualization Encapsulation 110 MPLS: Multiprotocol Label Switching 112 NVE: Network Virtualization Edge 114 TS: Tenant System 116 VAP: Virtual Access Point 118 VNI: Virtual Network Identifier 120 VXLAN: Virtual eXtensible Local Area Network 122 2.2. Requirements Language 124 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 125 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 126 "OPTIONAL" in this document are to be interpreted as described in BCP 127 14 [RFC2119] [RFC8174] when, and only when, they appear in all 128 capitals, as shown here. 130 3. BFD Packet Transmission over Geneve Tunnel 132 Concerning whether or not the Geneve data packets include an IP 133 protocol data unit, and whether or not the Geneve data packets 134 include an MPLS protocol data unit, this document considers three 135 options of BFD packet encapsulation in Geneve. 137 3.1. BFD Encapsulation With Inner Ethernet/IP/UDP Header 139 If the Protocol Type field (as defined in Section 3.4 of 140 [I-D.ietf-nvo3-geneve]) of data packets indicates that there exists 141 an inner Ethernet header, i.e., the Protocol Type equals to 0x6558 142 (Ethernet frame), then BFD packets are encapsulated in Geneve as 143 described below. The Geneve packet format over IPv4 is defined in 144 Section 3.1 of [I-D.ietf-nvo3-geneve]. The Geneve packet format over 145 IPv6 is defined in Section 3.2 of [I-D.ietf-nvo3-geneve]. The Outer 146 IP/UDP and Geneve headers MUST be encoded by the sender as defined in 147 [I-D.ietf-nvo3-geneve]. Note that the outer IP header and the inner 148 IP header may not be of the same address family, in other words, 149 outer IPv6 header accompanied with inner IPv4 header and outer IPv4 150 header accompanied with inner IPv6 header are both possible. 152 0 1 2 3 153 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 1 154 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 155 | | 156 ~ Outer Ethernet Header ~ 157 | | 158 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 159 | | 160 ~ Outer IPvX Header ~ 161 | | 162 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 163 | | 164 ~ Outer UDP Header ~ 165 | | 166 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 167 | | 168 ~ Geneve Header ~ 169 | | 170 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 171 | | 172 ~ Inner Ethernet Header ~ 173 | | 174 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 175 | | 176 ~ Inner IPvX Header ~ 177 | | 178 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 179 | | 180 ~ Inner UDP Header ~ 181 | | 182 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 183 | | 184 ~ BFD Control Message ~ 185 | | 186 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 187 | FCS | 188 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 190 Figure 1: Geneve Encapsulation of BFD Control Message With the Inner 191 Ethernet/IP/UDP Header 193 The BFD packet MUST be carried inside the inner Ethernet frame of the 194 Geneve packet, as specified in Section 4 of [I-D.ietf-bfd-vxlan]. 196 When the BFD packets are encapsulated in Geneve in this way, the 197 Geneve header follows the value set below. 199 0 1 2 3 200 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 1 201 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 202 |Ver| Opt Len |O|C| Rsvd. | Protocol Type | 203 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 204 | Virtual Network Identifier (VNI) | Reserved | 205 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 206 | Variable Length Options | 207 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 209 Figure 2: Geneve Header 211 Opt Len field SHOULD be set to 0, which indicates there isn't any 212 variable length option. 214 O bit MUST be set to 1, which indicates this packet contains a 215 control message. 217 C bit MUST be set to 0. 219 Protocol Type field MUST be set to 0x6558 (Ethernet frame). 221 3.2. BFD Encapsulation With Inner IP/UDP Header 223 If the Protocol Type field (as defined in Section 3.4 of 224 [I-D.ietf-nvo3-geneve]) of data packets indicates that there exists 225 an inner IP header, i.e., the Protocol Type equals to 0x0800 (IPv4) 226 or 0x86DD (IPv6), then BFD packets are encapsulated in Geneve as 227 described below. The Geneve packet format over IPv4 is defined in 228 Section 3.1 of [I-D.ietf-nvo3-geneve]. The Geneve packet format over 229 IPv6 is defined in Section 3.2 of [I-D.ietf-nvo3-geneve]. The Outer 230 IP/UDP and Geneve headers MUST be encoded by the sender as defined in 231 [I-D.ietf-nvo3-geneve]. Note that the outer IP header and the inner 232 IP header may not be of the same address family, in other words, 233 outer IPv6 header accompanied with inner IPv4 header and outer IPv4 234 header accompanied with inner IPv6 header are both possible. 236 0 1 2 3 237 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 1 238 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 239 | | 240 ~ Outer Ethernet Header ~ 241 | | 242 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 243 | | 244 ~ Outer IPvX Header ~ 245 | | 246 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 247 | | 248 ~ Outer UDP Header ~ 249 | | 250 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 251 | | 252 ~ Geneve Header ~ 253 | | 254 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 255 | | 256 ~ Inner IPvX Header ~ 257 | | 258 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 259 | | 260 ~ Inner UDP Header ~ 261 | | 262 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 263 | | 264 ~ BFD Control Message ~ 265 | | 266 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 267 | FCS | 268 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 270 Figure 3: Geneve Encapsulation of BFD Control Message With the Inner 271 IP/UDP Header 273 The BFD packet MUST be carried inside the inner IP packet of the 274 Geneve packet. The inner IP packet carrying the BFD payload has the 275 following format: 277 IP header: 279 Source IP: IP address of a VAP of the originating NVE. 281 Destination IP: IP address of a VAP of the terminating NVE. 283 TTL: MUST be set to 1 to ensure that the BFD packet is not 284 routed within the L3 underlay network. 286 The fields of the UDP header and the BFD control packet are 287 encoded as specified in [RFC5881]. 289 When the BFD packets are encapsulated in Geneve in this way, the 290 Geneve header follows the value set below. 292 Opt Len field SHOULD be set to 0, which indicates there isn't any 293 variable length option. 295 O bit MUST be set to 1, which indicates this packet contains a 296 control message. 298 C bit MUST be set to 0. 300 Protocol Type field MUST be set to 0x0800 (IPv4) or 0x86DD (IPv6), 301 depending on the address family of the inner IP packet. 303 3.3. BFD Encapsulation With Inner MPLS Header 305 If the Protocol Type field (as defined in Section 3.4 of 306 [I-D.ietf-nvo3-geneve]) of data packets indicates that there exists 307 an inner MPLS header, i.e., the Protocol Type equals to 0x8847 (MPLS) 308 or 0x8848 (MPLS with the upstream-assigned label), then BFD packets 309 are encapsulated in Geneve as described below. The Geneve packet 310 format over IPv4 is defined in Section 3.1 of [I-D.ietf-nvo3-geneve]. 311 The Geneve packet format over IPv6 is defined in Section 3.2 of 312 [I-D.ietf-nvo3-geneve]. The Outer IP/UDP and Geneve headers MUST be 313 encoded by the sender as defined in [I-D.ietf-nvo3-geneve]. 315 0 1 2 3 316 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 1 317 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 318 | | 319 ~ Outer Ethernet Header ~ 320 | | 321 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 322 | | 323 ~ Outer IPvX Header ~ 324 | | 325 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 326 | | 327 ~ Outer UDP Header ~ 328 | | 329 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 330 | | 331 ~ Geneve Header ~ 332 | | 333 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 334 | MPLS Interface Context Label | 335 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 336 | MPLS GAL | 337 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 338 | MPLS G-ACh | 339 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 340 | | 341 ~ BFD Control Message ~ 342 | | 343 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 344 | FCS | 345 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 347 Figure 4: Geneve Encapsulation of BFD Control Message With the Inner 348 MPLS GAL/G-ACh 350 The BFD packet MUST be carried inside the inner MPLS packet of the 351 Geneve packet. The inner MPLS packet carrying the BFD payload has 352 the following format: 354 MPLS Interface Context Label: This Label would be used to identify 355 a VAP of the originating NVE and a VAP of the terminating NVE. 357 MPLS GAL (Generic Associated Channel Label): 359 Label value: MUST be set to 13, as specified in [RFC5586]. 361 S bit: MUST be set to 1. 363 TTL: MUST be set to 1. 365 The fields of the MPLS G-ACh (Generic Associated Channel) and the 366 BFD control packet are encoded as specified for MPLS-TP CC 367 (Continuity Check) message in [RFC6428]. 369 When the BFD packets are encapsulated in Geneve in this way, the 370 Geneve header follows the value set below. 372 Opt Len field SHOULD be set to 0, which indicates there isn't any 373 variable length option. 375 O bit MUST be set to 1, which indicates this packet contains a 376 control message. 378 C bit MUST be set to 0. 380 Protocol Type field MUST be set to 0x8847 (MPLS). 382 4. Reception of BFD packet from Geneve Tunnel 384 Once a packet is received, NVE MUST validate the packet as described 385 in [I-D.ietf-nvo3-geneve]. 387 If the Protocol Type field equals 0x6558 (Ethernet frame), and the 388 Destination MAC of the inner Ethernet frame matches one MAC 389 address owned by the NVE, the Destination IP, the UDP destination 390 port and the TTL of the inner IP packet MUST be validated to 391 determine whether the received packet can be processed by BFD. 392 BFD packet with inner MAC set to NVE MUST NOT be forwarded to TSs. 394 If the Protocol Type field equals 0x0800 (IPv4) or 0x86DD (IPv6), 395 and the Destination IP of the inner IP packet matches a VAP IP 396 address of the NVE, the UDP destination port and the TTL of the 397 inner IP packet MUST be validated to determine whether the 398 received packet can be processed by BFD. BFD packet with inner IP 399 set to NVE MUST NOT be forwarded to TSs. 401 If the Protocol Type field equals 0x8847 (MPLS), the MPLS 402 Interface Context Label, the MPLS GAL and the MPLS G-ACh of the 403 inner MPLS packet MUST be validated to determine whether the 404 received packet can be processed by BFD. BFD packet with MPLS GAL 405 MUST NOT be forwarded to TSs. 407 4.1. Demultiplexing of the BFD packet 409 In BFD over Geneve, a BFD session is originated and terminated at 410 VAP, usually one NVE owns multiple VAPs, so multiple BFD sessions may 411 be running between two NVEs, there needs to be a mechanism for 412 demultiplexing received BFD packets to the proper session. 414 If the BFD packet is received with Your Discriminator equals to 0, 415 for different BFD encapsulation, the procedure for demultiplexing the 416 received BFD packets is different. 418 When the BFD Encapsulation With Inner Ethernet/IP/UDP Header is 419 used, the BFD session MUST be identified using the procedure 420 specified in Section 5.1 of [I-D.ietf-bfd-vxlan]. 422 When the BFD Encapsulation With Inner IP/UDP Header is used, the 423 BFD session MUST be identified using the inner IP/UDP header, 424 i.e., the source IP and the destination IP present in the inner 425 IP/UDP header. 427 When the BFD Encapsulation With Inner MPLS Header is used, the BFD 428 session MUST be identified using the inner MPLS header, i.e., the 429 MPLS Interface Context Label present in the inner MPLS header. 431 If the BFD packet is received with non-zero Your Discriminator, then 432 BFD session MUST be demultiplexed only with Your Discriminator as the 433 key. 435 With respect to BFD for Geneve, the use of the specific VNI would 436 follow the principle as specified in Section 6 of 437 [I-D.ietf-bfd-vxlan]. 439 [Ed.Note]: Currently it's still undetermined whether "BFD for VxLAN" 440 should allow multiple BFD sessions for the same VNI. The Editor 441 leans to believe "BFD for Geneve" should allow multiple BFD sessions 442 for the same VNI, and it needs further discussion. 444 5. Security Considerations 446 This document does not raise any additional security issues beyond 447 those of the specifications referred to in the list of normative 448 references. 450 6. IANA Considerations 452 This document has no IANA action requested. 454 7. Acknowledgements 456 The authors would like to acknowledge Reshad Rahman, Jeffrey Haas and 457 Matthew Bocci for their guidance on this work. 459 8. Normative References 461 [I-D.ietf-bfd-vxlan] 462 Networks, J., Paragiri, S., Govindan, V., Mudigonda, M., 463 and G. Mirsky, "BFD for VXLAN", draft-ietf-bfd-vxlan-07 464 (work in progress), May 2019. 466 [I-D.ietf-nvo3-geneve] 467 Gross, J., Ganga, I., and T. Sridhar, "Geneve: Generic 468 Network Virtualization Encapsulation", draft-ietf- 469 nvo3-geneve-14 (work in progress), September 2019. 471 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 472 Requirement Levels", BCP 14, RFC 2119, 473 DOI 10.17487/RFC2119, March 1997, 474 . 476 [RFC5586] Bocci, M., Ed., Vigoureux, M., Ed., and S. Bryant, Ed., 477 "MPLS Generic Associated Channel", RFC 5586, 478 DOI 10.17487/RFC5586, June 2009, 479 . 481 [RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection 482 (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010, 483 . 485 [RFC5881] Katz, D. and D. Ward, "Bidirectional Forwarding Detection 486 (BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881, 487 DOI 10.17487/RFC5881, June 2010, 488 . 490 [RFC6428] Allan, D., Ed., Swallow, G., Ed., and J. Drake, Ed., 491 "Proactive Connectivity Verification, Continuity Check, 492 and Remote Defect Indication for the MPLS Transport 493 Profile", RFC 6428, DOI 10.17487/RFC6428, November 2011, 494 . 496 [RFC7348] Mahalingam, M., Dutt, D., Duda, K., Agarwal, P., Kreeger, 497 L., Sridhar, T., Bursell, M., and C. Wright, "Virtual 498 eXtensible Local Area Network (VXLAN): A Framework for 499 Overlaying Virtualized Layer 2 Networks over Layer 3 500 Networks", RFC 7348, DOI 10.17487/RFC7348, August 2014, 501 . 503 [RFC7365] Lasserre, M., Balus, F., Morin, T., Bitar, N., and Y. 504 Rekhter, "Framework for Data Center (DC) Network 505 Virtualization", RFC 7365, DOI 10.17487/RFC7365, October 506 2014, . 508 [RFC8014] Black, D., Hudson, J., Kreeger, L., Lasserre, M., and T. 509 Narten, "An Architecture for Data-Center Network 510 Virtualization over Layer 3 (NVO3)", RFC 8014, 511 DOI 10.17487/RFC8014, December 2016, 512 . 514 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 515 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 516 May 2017, . 518 Authors' Addresses 520 Xiao Min 521 ZTE Corp. 522 Nanjing 523 China 525 Phone: +86 25 88013062 526 Email: xiao.min2@zte.com.cn 528 Greg Mirsky 529 ZTE Corp. 530 USA 532 Email: gregimirsky@gmail.com 534 Santosh Pallagatti 535 VMware 537 Email: santosh.pallagatti@gmail.com