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Checking references for intended status: Informational ---------------------------------------------------------------------------- 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. -------------------------------------------------------------------------------- 1 INTERNET-DRAFT Samer Salam 2 Intended Status: Informational Ali Sajassi 3 Cisco 4 Sam Aldrin 5 Google 6 John E. Drake 7 Juniper 8 Donald Eastlake 9 Futurewei 10 Expires: January 7, 2020 July 8, 2019 12 EVPN Operations, Administration and Maintenance 13 Requirements and Framework 14 draft-ietf-bess-evpn-oam-req-frmwk-01 16 Abstract 18 This document specifies the requirements and reference framework for 19 Ethernet VPN (EVPN) Operations, Administration and Maintenance (OAM). 20 The requirements cover the OAM aspects of EVPN and PBB-EVPN. The 21 framework defines the layered OAM model encompassing the EVPN service 22 layer, network layer and underlying Packet Switched Network (PSN) 23 transport layer. 25 Status of this Memo 27 This Internet-Draft is submitted to IETF in full conformance with the 28 provisions of BCP 78 and BCP 79. 30 Internet-Drafts are working documents of the Internet Engineering 31 Task Force (IETF), its areas, and its working groups. Note that 32 other groups may also distribute working documents as Internet- 33 Drafts. 35 Internet-Drafts are draft documents valid for a maximum of six months 36 and may be updated, replaced, or obsoleted by other documents at any 37 time. It is inappropriate to use Internet-Drafts as reference 38 material or to cite them other than as "work in progress." 40 The list of current Internet-Drafts can be accessed at 41 http://www.ietf.org/1id-abstracts.html. The list of Internet-Draft 42 Shadow Directories can be accessed at http://www.ietf.org/shadow.html 44 Copyright and License Notice 46 Copyright (c) 2019 IETF Trust and the persons identified as the 47 document authors. All rights reserved. 49 This document is subject to BCP 78 and the IETF Trust's Legal 50 Provisions Relating to IETF Documents 51 (http://trustee.ietf.org/license-info) in effect on the date of 52 publication of this document. Please review these documents 53 carefully, as they describe your rights and restrictions with respect 54 to this document. Code Components extracted from this document must 55 include Simplified BSD License text as described in Section 4.e of 56 the Trust Legal Provisions and are provided without warranty as 57 described in the Simplified BSD License. 59 Table of Contents 61 1. Introduction............................................4 62 1.1 Relationship to Other OAM Work.........................4 63 1.2 Specification of Requirements..........................5 64 1.3 Terminology............................................5 66 2. EVPN OAM Framework......................................6 67 2.1 OAM Layering...........................................6 68 2.2 EVPN Service OAM.......................................7 69 2.3 EVPN Network OAM.......................................7 70 2.4 Transport OAM for EVPN.................................9 71 2.5 Link OAM...............................................9 72 2.6 OAM Inter-working......................................9 74 3. EVPN OAM Requirements..................................11 75 3.1 Fault Management Requirements.........................11 76 3.1.1 Proactive Fault Management Functions................11 77 3.1.1.1 Fault Detection (Continuity Check)................11 78 3.1.1.2 Defect Indication.................................12 79 3.1.1.2.1 Forward Defect Indication.......................12 80 3.1.1.2.2 Reverse Defect Indication (RDI).................12 81 3.1.2 On-Demand Fault Management Functions................13 82 3.1.2.1 Connectivity Verification.........................13 83 3.1.2.2 Fault Isolation...................................14 84 3.2 Performance Management................................14 85 3.2.1 Packet Loss.........................................14 86 3.2.2 Packet Delay........................................15 88 4. Security Considerations................................16 90 5. Acknowledgements.......................................16 92 6. IANA Considerations....................................16 94 Normative References......................................17 95 Informative References....................................18 97 1. Introduction 99 This document specifies the requirements and defines a reference 100 framework for Ethernet VPN (EVPN) Operations, Administration and 101 Maintenance (OAM, [RFC6291]). In this context, we use the term EVPN 102 OAM to loosely refer to the OAM functions required for and/or 103 applicable to [RFC7432] and [RFC7623]. 105 EVPN is an Layer 2 VPN (L2VPN) solution for multipoint Ethernet 106 services, with advanced multi-homing capabilities, using BGP for 107 distributing customer/client MAC address reachability information 108 over the core MPLS/IP network. 110 PBB-EVPN combines Provider Backbone Bridging (PBB) [802.1Q] with EVPN 111 in order to reduce the number of BGP MAC advertisement routes, 112 provide client MAC address mobility using C-MAC aggregation and B-MAC 113 sub-netting, confine the scope of C-MAC learning to only active 114 flows, offer per site policies, and avoid C-MAC address flushing on 115 topology changes. 117 This document focuses on the fault management and performance 118 management aspects of EVPN OAM. 120 1.1 Relationship to Other OAM Work 122 This document leverages concepts and draws upon elements defined 123 and/or used in the following documents: 125 [RFC6136] specifies the requirements and a reference model for OAM as 126 it relates to L2VPN services, pseudowires and associated Packet 127 Switched Network (PSN) tunnels. This document focuses on VPLS and 128 VPWS solutions and services. 130 [RFC8029] defines mechanisms for detecting data plane failures in 131 MPLS LSPs, including procedures to check the correct operation of the 132 data plane, as well as mechanisms to verify the data plane against 133 the control plane. 135 [802.1Q] specifies the Ethernet Connectivity Fault Management (CFM) 136 protocol, which defines the concepts of Maintenance Domains, 137 Maintenance Associations, Maintenance End Points, and Maintenance 138 Intermediate Points. 140 [Y.1731] extends Connectivity Fault Management in the following 141 areas: it defines fault notification and alarm suppression functions 142 for Ethernet. It also specifies mechanisms for Ethernet performance 143 management, including loss, delay, jitter, and throughput 144 measurement. 146 1.2 Specification of Requirements 148 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 149 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 150 document are to be interpreted as described in [RFC2119] [RFC8174] 151 when, and only when, they appear in all capitals, as shown here. 153 1.3 Terminology 155 This document uses the following terminology defined in [RFC6136]: 157 MA Maintenance Association is a set of MEPs belonging to the same 158 Maintenance Domain, established to verify the integrity of a 159 single service instance. 161 MEP Maintenance End Point is responsible for origination and 162 termination of OAM frames for a given MA. 164 MIP Maintenance Intermediate Point is located between peer MEPs and 165 can process and respond to certain OAM frames but does not 166 initiate them. 168 MD Maintenance Domain, an OAM Domain that represents a region over 169 which OAM frames can operate unobstructed. 171 2. EVPN OAM Framework 173 2.1 OAM Layering 175 Multiple layers come into play for implementing an L2VPN service 176 using the EVPN family of solutions: 178 - The Service Layer runs end to end between the sites or Ethernet 179 Segments that are being interconnected by the EVPN solution. 181 - The Network Layer extends in between the EVPN PE nodes and is 182 mostly transparent to the core nodes (except where Flow Entropy 183 comes into play). It leverages MPLS for service (i.e. EVI) 184 multiplexing and Split-Horizon functions. 186 - The Transport Layer is dictated by the networking technology of the 187 PSN. It may be either based on MPLS LSPs or IP. 189 - The Link Layer is dependent upon the physical technology used. 190 Ethernet is a popular choice for this layer, but other alternatives 191 are deployed (e.g. POS, DWDM etc.). 193 This layering extends to the set of OAM protocols that are involved 194 in the ongoing maintenance and diagnostics of EVPN networks. The 195 figure below depicts the OAM layering, and shows which devices have 196 visibility into what OAM layer(s). 198 +---+ +---+ 199 +--+ | | +---+ +---+ +---+ | | +--+ 200 |CE|----|PE1|----| P |----| P |----| P |----|PE2|----|CE| 201 +--+ | | +---+ +---+ +---+ | | +--+ 202 +---+ +---+ 204 o--------o--------- Service OAM -------------o--------o 206 o----------- Network OAM -----------o 208 o--------o--------o---------o-------o Transport OAM 210 o-----o o-----o o-----o o-----o o-----o o-----o Link OAM 212 Figure 1: OAM Layering 214 Figure 2 below shows an example network where native Ethernet domains 215 are interconnected via EVPN, and the OAM mechanisms applicable at 216 each layer. The details of the layers are described in the sections 217 below. 219 +---+ +---+ 220 +--+ | | +---+ +---+ +---+ | | +--+ 221 |CE|----|PE1|----| P |----| P |----| P |----|PE2|----|CE| 222 +--+ | | +---+ +---+ +---+ | | +--+ 223 +---+ +---+ 225 o--------o--------- Service CFM -------------o--------o 227 o-------- EVPN Network OAM ---------o 229 o--------o--------o---------o-------o MPLS OAM 231 o-----o o-----o o-----o o-----o o-----o o-----o 802.3 OAM 233 Figure 2: EVPN OAM Example 235 2.2 EVPN Service OAM 237 The EVPN Service OAM protocol depends on what service layer 238 technology is being interconnected by the EVPN solution. In case of 239 [RFC7432] and [RFC7623], the service layer is Ethernet; hence, the 240 corresponding service OAM protocol is Ethernet Connectivity Fault 241 Management (CFM) [802.1Q]. 243 EVPN service OAM is visible to the CEs and EVPN PEs, but not to the 244 core (P) nodes. This is because the PEs operate at the Ethernet MAC 245 layer in [RFC7432] [RFC7623] whereas the P nodes do not. 247 The EVPN PE MUST support MIP functions in the applicable service OAM 248 protocol, for example Ethernet CFM. The EVPN PE SHOULD support MEP 249 functions in the applicable service OAM protocol. This includes both 250 Up and Down MEP functions. 252 The EVPN PE MUST learn the MAC address of locally attached CE MEPs by 253 snooping on CFM frames and advertising them to remote PEs as a MAC/IP 254 Advertisement route. 256 The EVPN PE SHOULD advertise any MEP/MIP local to the PE as a MAC/IP 257 Advertisement route. Since these are not subject to mobility, they 258 SHOULD be advertised with the stick bit set (see Section 15.2 of 259 [RFC7432]). 261 2.3 EVPN Network OAM 263 EVPN Network OAM is visible to the PE nodes only. This OAM layer is 264 analogous to VCCV [RFC5085] in the case of VPLS/VPWS. It provides 265 mechanisms to check the correct operation of the data plane, as well 266 as a mechanism to verify the data plane against the control plane. 267 This includes the ability to perform fault detection and diagnostics 268 on: 270 - the MP2P tunnels used for the transport of unicast traffic between 271 PEs. EVPN allows for three different models of unicast label 272 assignment: label per EVI, label per and label 273 per MAC address. In all three models, the label is bound to an EVPN 274 Unicast FEC. 276 EVPN Network OAM MUST provide mechanisms to check the operation of 277 the data plane and verify that operation against the control plane 278 view. 280 - the MP2P tunnels used for aliasing unicast traffic destined to a 281 multi-homed Ethernet Segment. The three label assignment models, 282 discussed above, apply here as well. In all three models, the label 283 is bound to an EVPN Aliasing FEC. EVPN Network OAM MUST provide 284 mechanisms to check the operation of the data plane and verify that 285 operation against the control plane view. 287 - the multicast tunnels (either MP2P or P2MP) used for the transport 288 of broadcast, unknown unicast and multicast traffic between PEs. In 289 the case of ingress replication, a label is allocated per EVI or 290 per and is bound to an EVPN Multicast FEC. In 291 the case of LSM, and more specifically aggregate inclusive trees, 292 again a label may be allocated per EVI or per 293 and is bound to the tunnel FEC. 295 - the correct operation of the ESI split-horizon filtering function. 296 In EVPN, a label is allocated per multi-homed Ethernet Segment for 297 the purpose of performing the access split-horizon enforcement. The 298 label is bound to an EVPN Ethernet Segment. 300 - the correct operation of the DF filtering function. 302 EVPN Network OAM MUST provide mechanisms to check the operation of 303 the data plane and verify that operation against the control plane 304 view for the DF filtering function. 306 EVPN network OAM mechanisms MUST provide in-band management 307 capabilities. As such, OAM messages MUST be encoded so that they 308 exhibit identical entropy characteristics to data traffic. 310 EVPN network OAM SHOULD provide both proactive and on-demand 311 mechanisms of monitoring the data plane operation and data plane 312 conformance to the state of the control plane. 314 2.4 Transport OAM for EVPN 316 The transport OAM protocol depends on the nature of the underlying 317 transport technology in the PSN. MPLS OAM mechanisms [RFC8029] 318 [RFC6425] as well as ICMP [RFC792] are applicable, depending on 319 whether the PSN employs MPLS or IP transport, respectively. 320 Furthermore, BFD mechanisms per [RFC5880], [RFC5881], [RFC5883] and 321 [RFC5884] apply. Also, the BFD mechanisms pertaining to MPLS-TP LSPs 322 per [RFC6428] are applicable. 324 2.5 Link OAM 326 Link OAM depends on the data link technology being used between the 327 PE and P nodes. For example, if Ethernet links are employed, then 328 Ethernet Link OAM [802.3] Clause 57 may be used. 330 2.6 OAM Inter-working 332 When inter-working two networking domains, such as native Ethernet 333 and EVPN to provide an end-to-end emulated service, there is a need 334 to identify the failure domain and location, even when a PE supports 335 both the Service OAM mechanisms and the EVPN Network OAM mechanisms. 336 In addition, scalability constraints may not allow running proactive 337 monitoring, such as Ethernet Continuity Check Messages (CCMs), at a 338 PE to detect the failure of an EVI across the EVPN domain. Thus, the 339 mapping of alarms generated upon failure detection in one domain 340 (e.g. native Ethernet or EVPN network domain) to the other domain is 341 needed. There are also cases where a PE may not be able to process 342 Service OAM messages received from a remote PE over the PSN even when 343 such messages are defined, as in the Ethernet case, thereby 344 necessitating support for fault notification message mapping between 345 the EVPN Network domain and the Service domain. 347 OAM inter-working is not limited though to scenarios involving 348 disparate network domains. It is possible to perform OAM inter- 349 working across different layers in the same network domain. In 350 general, alarms generated within an OAM layer, as a result of 351 proactive fault detection mechanisms, may be injected into its client 352 layer OAM mechanisms. This allows the client layer OAM to trigger 353 event-driven (i.e. asynchronous) fault notifications. For example, 354 alarms generated by the Link OAM mechanisms may be injected into the 355 Transport OAM layer, and alarms generated by the Transport OAM 356 mechanism may be injected into the Network OAM mechanism, and so on. 358 EVPN OAM MUST support inter-working between the Network OAM and 359 Service OAM mechanisms. EVPN OAM MAY support inter-working among 360 other OAM layers. 362 3. EVPN OAM Requirements 364 This section discusses the EVPN OAM requirements pertaining to Fault 365 Management and Performance Management. 367 3.1 Fault Management Requirements 369 3.1.1 Proactive Fault Management Functions 371 The network operator configures proactive fault management functions 372 to run periodically without a time bound. Certain actions, for 373 example protection switchover or alarm indication signaling, can be 374 associated with specific events, such as entering or clearing fault 375 states. 377 3.1.1.1 Fault Detection (Continuity Check) 379 Proactive fault detection is performed by periodically monitoring the 380 reachability between service endpoints, i.e. MEPs in a given MA, 381 through the exchange of Continuity Check messages. The reachability 382 between any two arbitrary MEPs may be monitored for: 384 - in-band per-flow monitoring. This enables per flow monitoring 385 between MEPs. EVPN Network OAM MUST support fault detection with 386 per user flow granularity. EVPN Service OAM MAY support fault 387 detection with per user flow granularity. 389 - a representative path. This enables liveness check of the nodes 390 hosting the MEPs assuming that the loss of continuity to the MEP is 391 interpreted as a failure of the hosting node. This, however, does 392 not conclusively indicate liveness of the path(s) taken by user 393 data traffic. This enables node failure detection but not path 394 failure detection, through the use of a test flow. EVPN Network OAM 395 and Service OAM MUST support fault detection using test flows. 397 - all paths. For MPLS/IP networks with ECMP, monitoring of all 398 unicast paths between MEPs (on non-adjacent nodes) may not be 399 possible, since the per-hop ECMP hashing behavior may yield 400 situations where it is impossible for a MEP to pick flow entropy 401 characteristics that result in exercising the exhaustive set of 402 ECMP paths. Monitoring of all ECMP paths between MEPs (on non- 403 adjacent nodes) is not a requirement for EVPN OAM. 405 The fact that MPLS/IP networks do not enforce congruency between 406 unicast and multicast paths means that the proactive fault detection 407 mechanisms for EVPN networks MUST provide procedures to monitor the 408 unicast paths independently of the multicast paths. This applies to 409 EVPN Service OAM and Network OAM. 411 3.1.1.2 Defect Indication 413 EVPN Service OAM MUST support event-driven defect indication upon the 414 detection of a connectivity defect. Defect indications can be 415 categorized into two types: forward and reverse defect indications. 417 3.1.1.2.1 Forward Defect Indication 419 This is used to signal a failure that is detected by a lower layer 420 OAM mechanism. A server MEP (i.e. an actual or virtual MEP) transmits 421 a Forward Defect Indication in a direction that is away from the 422 direction of the failure (refer to Figure 3 below). 424 Failure 425 | 426 +-----+ +-----+ V +-----+ +-----+ 427 | A |------| B |--XXX--| C |------| D | 428 +-----+ +-----+ +-----+ +-----+ 430 <===========| |============> 431 Forward Forward 432 Defect Defect 433 Indication Indication 435 Figure 3: Forward Defect Indication 437 Forward defect indication may be used for alarm suppression and/or 438 for purpose of inter-working with other layer OAM protocols. Alarm 439 suppression is useful when a transport/network level fault translates 440 to multiple service or flow level faults. In such a scenario, it is 441 enough to alert a network management station (NMS) of the single 442 transport/network level fault in lieu of flooding that NMS with a 443 multitude of Service or Flow granularity alarms. EVPN PEs SHOULD 444 support Forward Defect Indication in the Service OAM mechanisms. 446 3.1.1.2.2 Reverse Defect Indication (RDI) 448 RDI is used to signal that the advertising MEP has detected a loss of 449 continuity (LoC) defect. RDI is transmitted in the direction of the 450 failure (refer to Figure 4). 452 Failure 453 | 454 +-----+ +-----+ V +-----+ +-----+ 455 | A |------| B |--XXX--| C |------| D | 456 +-----+ +-----+ +-----+ +-----+ 458 |===========> <============| 459 Reverse Reverse 460 Defect Defect 461 Indication Indication 463 Figure 4: Reverse Defect Indication 465 RDI allows single-sided management, where the network operator can 466 examine the state of a single MEP and deduce the overall health of a 467 monitored service. EVPN PEs SHOULD support Reverse Defect Indication 468 in the Service OAM mechanisms. This includes both the ability to 469 signal LoC defect to a remote MEP, as well as the ability to 470 recognize RDI from a remote MEP. Note that, in a multipoint MA, RDI 471 is not a useful indicator of unidirectional fault. This is because 472 RDI carries no indication of the affected MEP(s) with which the 473 sender had detected a LoC defect. 475 3.1.2 On-Demand Fault Management Functions 477 On-demand fault management functions are initiated manually by the 478 network operator and continue for a time bound period. These 479 functions enable the operator to run diagnostics to investigate a 480 defect condition. 482 3.1.2.1 Connectivity Verification 484 EVPN Network OAM MUST support on-demand connectivity verification 485 mechanisms for unicast and multicast destinations. The connectivity 486 verification mechanisms SHOULD provide a means for specifying and 487 carrying in the messages: 489 - variable length payload/padding to test MTU related connectivity 490 problems. 492 - test frame formats as defined in Appendix C of [RFC2544] to detect 493 potential packet corruption. 495 EVPN Network OAM MUST support connectivity verification at per flow 496 granularity. This includes both user flows (to test a specific path 497 between PEs) as well as test flows (to rest a representative path 498 between PEs). 500 EVPN Service OAM MUST support connectivity verification on test flows 501 and MAY support connectivity verification on user flows. 503 For multicast connectivity verification, EVPN Network OAM MUST 504 support reporting on: 506 - the DF filtering status of specific port(s) or all the ports in a 507 given bridge-domain. 509 - the Split Horizon filtering status of specific port(s) or all the 510 ports in a given bridge-domain. 512 3.1.2.2 Fault Isolation 514 EVPN OAM MUST support an on-demand fault localization function. This 515 involves the capability to narrow down the locality of a fault to a 516 particular port, link or node. The characteristic of forward/reverse 517 path asymmetry, in MPLS/IP, renders fault isolation into a direction- 518 sensitive operation. That is, given two PEs A and B, localization of 519 continuity failures between them requires running fault isolation 520 procedures from PE A to PE B as well as from PE B to PE A. 522 EVPN Service OAM mechanisms only have visibility to the PEs but not 523 the MPLS/IP P nodes. As such, they can be used to deduce whether the 524 fault is in the customer's own network, the local CE-PE segment or 525 remote CE-PE segment(s). EVPN Network and Transport OAM mechanisms 526 can be used for fault isolation between the PEs and P nodes. 528 3.2 Performance Management 530 Performance Management functions can be performed both proactively 531 and on-demand. Proactive management involves a recurring function, 532 where the performance management probes are run continuously without 533 a trigger. We cover both proactive and on-demand functions in this 534 section. 536 3.2.1 Packet Loss 538 EVPN Network OAM SHOULD provide mechanisms for measuring packet loss 539 for a given service. 541 Given that EVPN provides inherent support for multipoint-to- 542 multipoint connectivity, then packet loss cannot be accurately 543 measured by means of counting user data packets. This is because user 544 packets can be delivered to more PEs or more ports than are necessary 545 (e.g. due to broadcast, un-pruned multicast or unknown unicast 546 flooding). As such, a statistical means of approximating packet loss 547 rate is required. This can be achieved by sending "synthetic" OAM 548 packets that are counted only by those ports (MEPs) that are required 549 to receive them. This provides a statistical approximation of the 550 number of data frames lost, even with multipoint-to-multipoint 551 connectivity. 553 3.2.2 Packet Delay 555 EVPN Service OAM SHOULD support measurement of one-way and two-way 556 packet delay and delay variation (jitter) across the EVPN network. 557 Measurement of one-way delay requires clock synchronization between 558 the probe source and target devices. Mechanisms for clock 559 synchronization are outside the scope of this document. Note that 560 Service OAM performance management mechanisms defined in [Y.1731] can 561 be used. 563 EVPN Network OAM MAY support measurement of one-way and two-way 564 packet delay and delay variation (jitter) across the EVPN network. 566 4. Security Considerations 568 EVPN OAM must provide mechanisms for: 570 - Preventing denial of service attacks caused by exploitation of the 571 OAM message channel. 573 - Optionally authenticate communicating endpoints (MEPs and MIPs) 575 - Preventing OAM packets from leaking outside of the EVPN network or 576 outside their corresponding Maintenance Domain. This can be done by 577 having MEPs implement a filtering function based on the Maintenance 578 Level associated with received OAM packets. 580 5. Acknowledgements 582 The authors would like to thank the following for their review of 583 this work and valuable comments: 585 Gregory Mirsky, Alexander Vainshtein 587 6. IANA Considerations 589 This document requires no IANA actions. 591 Normative References 593 [RFC792] Postel, J., "Internet Control Message Protocol", STD 5, RFC 594 792, DOI 10.17487/RFC0792, September 1981, 595 . 597 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 598 Requirement Levels", BCP 14, RFC 2119, DOI 599 10.17487/RFC2119, March 1997, . 602 [RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection 603 (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010, 604 . 606 [RFC5881] Katz, D. and D. Ward, "Bidirectional Forwarding Detection 607 (BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881, DOI 608 10.17487/RFC5881, June 2010, . 611 [RFC5883] Katz, D. and D. Ward, "Bidirectional Forwarding Detection 612 (BFD) for Multihop Paths", RFC 5883, DOI 10.17487/RFC5883, 613 June 2010, . 615 [RFC5884] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, 616 "Bidirectional Forwarding Detection (BFD) for MPLS Label 617 Switched Paths (LSPs)", RFC 5884, DOI 10.17487/RFC5884, 618 June 2010, .< 620 [RFC6291] Andersson, L., van Helvoort, H., Bonica, R., Romascanu, D., 621 and S. Mansfield, "Guidelines for the Use of the "OAM" 622 Acronym in the IETF", BCP 161, RFC 6291, DOI 623 10.17487/RFC6291, June 2011, . 626 [RFC6425] Saxena, S., Ed., Swallow, G., Ali, Z., Farrel, A., 627 Yasukawa, S., and T. Nadeau, "Detecting Data-Plane Failures 628 in Point-to-Multipoint MPLS - Extensions to LSP Ping", RFC 629 6425, DOI 10.17487/RFC6425, November 2011, 630 . 632 [RFC6428] Allan, D., Ed., Swallow, G., Ed., and J. Drake, Ed., 633 "Proactive Connectivity Verification, Continuity Check, and 634 Remote Defect Indication for the MPLS Transport Profile", 635 RFC 6428, DOI 10.17487/RFC6428, November 2011, 636 . 638 [RFC7432] Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A., 639 Uttaro, J., Drake, J., and W. Henderickx, "BGP MPLS-Based 640 Ethernet VPN", RFC 7432, DOI 10.17487/RFC7432, February 641 2015, . 643 [RFC7623] Sajassi, A., Ed., Salam, S., Bitar, N., Isaac, A., and W. 644 Henderickx, "Provider Backbone Bridging Combined with 645 Ethernet VPN (PBB-EVPN)", RFC 7623, DOI 10.17487/RFC7623, 646 September 2015, . 648 [RFC8029] Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N., 649 Aldrin, S., and M. Chen, "Detecting Multiprotocol Label 650 Switched (MPLS) Data-Plane Failures", RFC 8029, DOI 651 10.17487/RFC8029, March 2017, . 654 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 655 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 656 2017, 658 Informative References 660 [802.1Q] "IEEE Standard for Local and metropolitan area networks - 661 Media Access Control (MAC) Bridges and Virtual Bridge Local 662 Area Networks", 2014. 664 [Y.1731] "ITU-T Recommendation Y.1731 (02/08) - OAM functions and 665 mechanisms for Ethernet based networks", February 2008. 667 [RFC2544] Bradner, S. and J. McQuaid, "Benchmarking Methodology for 668 Network Interconnect Devices", RFC 2544, DOI 669 10.17487/RFC2544, March 1999, . 672 [RFC5085] Nadeau, T., Ed., and C. Pignataro, Ed., "Pseudowire Virtual 673 Circuit Connectivity Verification (VCCV): A Control Channel 674 for Pseudowires", RFC 5085, DOI 10.17487/RFC5085, December 675 2007, . 677 [RFC6136] Sajassi, A., Ed., and D. Mohan, Ed., "Layer 2 Virtual 678 Private Network (L2VPN) Operations, Administration, and 679 Maintenance (OAM) Requirements and Framework", RFC 6136, 680 DOI 10.17487/RFC6136, March 2011, . 683 Authors' Addresses 685 Samer Salam 686 Cisco 688 Email: ssalam@cisco.com 690 Ali Sajassi 691 Cisco 692 170 West Tasman Drive 693 San Jose, CA 95134, USA 695 Email: sajassi@cisco.com 697 Sam Aldrin 698 Google, Inc. 699 1600 Amphitheatre Parkway 700 Mountain View, CA USA 702 Email: aldrin.ietf@gmail.com 704 John E. Drake 705 Juniper Networks 706 1194 N. Mathilda Ave. 707 Sunnyvale, CA 94089, USA 709 Email: jdrake@juniper.net 711 Donald E. Eastlake, 3rd 712 Futurewei Technologies 713 1424 Pro Shop Court 714 Davenport, FL 33896 USA 716 Tel: +1-508-333-2270 717 Email: d3e3e3@gmail.com