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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: June 31, 2020 January 1, 2020 12 EVPN Operations, Administration and Maintenance 13 Requirements and Framework 14 draft-ietf-bess-evpn-oam-req-frmwk-02 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) 2020 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 89 5. Acknowledgements.......................................16 90 6. IANA Considerations....................................16 92 Normative References......................................17 93 Informative References....................................18 95 1. Introduction 97 This document specifies the requirements and defines a reference 98 framework for Ethernet VPN (EVPN) Operations, Administration and 99 Maintenance (OAM, [RFC6291]). In this context, we use the term EVPN 100 OAM to loosely refer to the OAM functions required for and/or 101 applicable to [RFC7432] and [RFC7623]. 103 EVPN is an Layer 2 VPN (L2VPN) solution for multipoint Ethernet 104 services, with advanced multi-homing capabilities, using BGP for 105 distributing customer/client MAC address reachability information 106 over the core MPLS/IP network. 108 PBB-EVPN combines Provider Backbone Bridging (PBB) [802.1Q] with EVPN 109 in order to reduce the number of BGP MAC advertisement routes, 110 provide client MAC address mobility using C-MAC aggregation and B-MAC 111 sub-netting, confine the scope of C-MAC learning to only active 112 flows, offer per site policies, and avoid C-MAC address flushing on 113 topology changes. 115 This document focuses on the fault management and performance 116 management aspects of EVPN OAM. 118 1.1 Relationship to Other OAM Work 120 This document leverages concepts and draws upon elements defined 121 and/or used in the following documents: 123 [RFC6136] specifies the requirements and a reference model for OAM as 124 it relates to L2VPN services, pseudowires and associated Packet 125 Switched Network (PSN) tunnels. This document focuses on VPLS and 126 VPWS solutions and services. 128 [RFC8029] defines mechanisms for detecting data plane failures in 129 MPLS LSPs, including procedures to check the correct operation of the 130 data plane, as well as mechanisms to verify the data plane against 131 the control plane. 133 [802.1Q] specifies the Ethernet Connectivity Fault Management (CFM) 134 protocol, which defines the concepts of Maintenance Domains, 135 Maintenance Associations, Maintenance End Points, and Maintenance 136 Intermediate Points. 138 [Y.1731] extends Connectivity Fault Management in the following 139 areas: it defines fault notification and alarm suppression functions 140 for Ethernet. It also specifies mechanisms for Ethernet performance 141 management, including loss, delay, jitter, and throughput 142 measurement. 144 1.2 Specification of Requirements 146 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 147 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 148 document are to be interpreted as described in [RFC2119] [RFC8174] 149 when, and only when, they appear in all capitals, as shown here. 151 1.3 Terminology 153 This document uses the following terminology defined in [RFC6136]: 155 CE Customer Edge device, e.g., a host, router, or switch. 157 DF Designated Forwarder 159 EVI An EVPN instance spanning the Provider Edge (PE) devices 160 participating in that EVPN. 162 MA Maintenance Association is a set of MEPs belonging to the same 163 Maintenance Domain, established to verify the integrity of a 164 single service instance. 166 MEP Maintenance End Point is responsible for origination and 167 termination of OAM frames for a given MA. 169 MIP Maintenance Intermediate Point is located between peer MEPs and 170 can process and respond to certain OAM frames but does not 171 initiate them. 173 MD Maintenance Domain, an OAM Domain that represents a region over 174 which OAM frames can operate unobstructed. 176 MP2P Multipoint to Point. 178 P2MP Point to Multipoint. 180 PE Provider Edge device. 182 2. EVPN OAM Framework 184 2.1 OAM Layering 186 Multiple layers come into play for implementing an L2VPN service 187 using the EVPN family of solutions: 189 - The Service Layer runs end to end between the sites or Ethernet 190 Segments that are being interconnected by the EVPN solution. 192 - The Network Layer extends between the EVPN PE nodes and is mostly 193 transparent to the core nodes (except where Flow Entropy comes into 194 play). It leverages MPLS for service (i.e. EVI) multiplexing and 195 Split-Horizon functions. 197 - The Transport Layer is dictated by the networking technology of the 198 PSN. It may be either based on MPLS LSPs or IP. 200 - The Link Layer is dependent upon the physical technology used. 201 Ethernet is a popular choice for this layer, but other alternatives 202 are deployed (e.g. POS, DWDM etc.). 204 This layering extends to the set of OAM protocols that are involved 205 in the ongoing maintenance and diagnostics of EVPN networks. The 206 figure below depicts the OAM layering, and shows which devices have 207 visibility into what OAM layer(s). 209 +---+ +---+ 210 +--+ | | +---+ +---+ +---+ | | +--+ 211 |CE|----|PE1|----| P |----| P |----| P |----|PE2|----|CE| 212 +--+ | | +---+ +---+ +---+ | | +--+ 213 +---+ +---+ 215 o--------o--------- Service OAM -------------o--------o 217 o----------- Network OAM -----------o 219 o--------o--------o---------o-------o Transport OAM 221 o-----o o-----o o-----o o-----o o-----o o-----o Link OAM 223 Figure 1: OAM Layering 225 Figure 2 below shows an example network where native Ethernet domains 226 are interconnected via EVPN, and the OAM mechanisms applicable at 227 each layer. The details of the layers are described in the sections 228 below. 230 +---+ +---+ 231 +--+ | | +---+ +---+ +---+ | | +--+ 232 |CE|----|PE1|----| P |----| P |----| P |----|PE2|----|CE| 233 +--+ | | +---+ +---+ +---+ | | +--+ 234 +---+ +---+ 236 o--------o--------- Service CFM -------------o--------o 238 o-------- EVPN Network OAM ---------o 240 o--------o--------o---------o-------o MPLS OAM 242 o-----o o-----o o-----o o-----o o-----o o-----o 802.3 OAM 244 Figure 2: EVPN OAM Example 246 2.2 EVPN Service OAM 248 The EVPN Service OAM protocol depends on what service layer 249 technology is being interconnected by the EVPN solution. In case of 250 [RFC7432] and [RFC7623], the service layer is Ethernet; hence, the 251 corresponding service OAM protocol is Ethernet Connectivity Fault 252 Management (CFM) [802.1Q]. 254 EVPN service OAM is visible to the CEs and EVPN PEs, but not to the 255 core (P) nodes. This is because the PEs operate at the Ethernet MAC 256 layer in [RFC7432] [RFC7623] whereas the P nodes do not. 258 The EVPN PE MUST support MIP functions in the applicable service OAM 259 protocol, for example Ethernet CFM. The EVPN PE SHOULD support MEP 260 functions in the applicable service OAM protocol. This includes both 261 Up and Down MEP functions. 263 The EVPN PE MUST learn the MAC address of locally attached CE MEPs by 264 snooping on CFM frames and advertising them to remote PEs as a MAC/IP 265 Advertisement route. 267 The EVPN PE SHOULD advertise any MEP/MIP local to the PE as a MAC/IP 268 Advertisement route. Since these are not subject to mobility, they 269 SHOULD be advertised with the static (sticky) bit set (see Section 270 15.2 of [RFC7432]). 272 2.3 EVPN Network OAM 274 EVPN Network OAM is visible to the PE nodes only. This OAM layer is 275 analogous to VCCV [RFC5085] in the case of VPLS/VPWS. It provides 276 mechanisms to check the correct operation of the data plane, as well 277 as a mechanism to verify the data plane against the control plane. 278 This includes the ability to perform fault detection and diagnostics 279 on: 281 - the MP2P tunnels used for the transport of unicast traffic between 282 PEs. EVPN allows for three different models of unicast label 283 assignment: label per EVI, label per and label 284 per MAC address. In all three models, the label is bound to an EVPN 285 Unicast FEC. 287 EVPN Network OAM MUST provide mechanisms to check the operation of 288 the data plane and verify that operation against the control plane 289 view. 291 - the MP2P tunnels used for aliasing unicast traffic destined to a 292 multi-homed Ethernet Segment. The three label assignment models, 293 discussed above, apply here as well. In all three models, the label 294 is bound to an EVPN Aliasing FEC. EVPN Network OAM MUST provide 295 mechanisms to check the operation of the data plane and verify that 296 operation against the control plane view. 298 - the multicast tunnels (either MP2P or P2MP) used for the transport 299 of broadcast, unknown unicast and multicast traffic between PEs. In 300 the case of ingress replication, a label is allocated per EVI or 301 per and is bound to an EVPN Multicast FEC. In 302 the case of LSM, and more specifically aggregate inclusive trees, 303 again a label may be allocated per EVI or per 304 and is bound to the tunnel FEC. 306 - the correct operation of the ESI split-horizon filtering function. 307 In EVPN, a label is allocated per multi-homed Ethernet Segment for 308 the purpose of performing the access split-horizon enforcement. The 309 label is bound to an EVPN Ethernet Segment. 311 - the correct operation of the DF filtering function. 313 EVPN Network OAM MUST provide mechanisms to check the operation of 314 the data plane and verify that operation against the control plane 315 view for the DF filtering function. 317 EVPN network OAM mechanisms MUST provide in-band management 318 capabilities. As such, OAM messages MUST be encoded so that they 319 exhibit identical entropy characteristics to data traffic. 321 EVPN network OAM SHOULD provide both proactive and on-demand 322 mechanisms of monitoring the data plane operation and data plane 323 conformance to the state of the control plane. 325 2.4 Transport OAM for EVPN 327 The transport OAM protocol depends on the nature of the underlying 328 transport technology in the PSN. MPLS OAM mechanisms [RFC8029] 329 [RFC6425] as well as ICMP [RFC792] are applicable, depending on 330 whether the PSN employs MPLS or IP transport, respectively. 331 Furthermore, BFD mechanisms per [RFC5880], [RFC5881], [RFC5883] and 332 [RFC5884] apply. Also, the BFD mechanisms pertaining to MPLS-TP LSPs 333 per [RFC6428] are applicable. 335 2.5 Link OAM 337 Link OAM depends on the data link technology being used between the 338 PE and P nodes. For example, if Ethernet links are employed, then 339 Ethernet Link OAM [802.3] Clause 57 may be used. 341 2.6 OAM Inter-working 343 When inter-working two networking domains, such as native Ethernet 344 and EVPN to provide an end-to-end emulated service, there is a need 345 to identify the failure domain and location, even when a PE supports 346 both the Service OAM mechanisms and the EVPN Network OAM mechanisms. 347 In addition, scalability constraints may not allow running proactive 348 monitoring, such as Ethernet Continuity Check Messages (CCMs), at a 349 PE to detect the failure of an EVI across the EVPN domain. Thus, the 350 mapping of alarms generated upon failure detection in one domain 351 (e.g. native Ethernet or EVPN network domain) to the other domain is 352 needed. There are also cases where a PE may not be able to process 353 Service OAM messages received from a remote PE over the PSN even when 354 such messages are defined, as in the Ethernet case, thereby 355 necessitating support for fault notification message mapping between 356 the EVPN Network domain and the Service domain. 358 OAM inter-working is not limited though to scenarios involving 359 disparate network domains. It is possible to perform OAM inter- 360 working across different layers in the same network domain. In 361 general, alarms generated within an OAM layer, as a result of 362 proactive fault detection mechanisms, may be injected into its client 363 layer OAM mechanisms. This allows the client layer OAM to trigger 364 event-driven (i.e., asynchronous) fault notifications. For example, 365 alarms generated by the Link OAM mechanisms may be injected into the 366 Transport OAM layer, and alarms generated by the Transport OAM 367 mechanism may be injected into the Network OAM mechanism, and so on. 369 EVPN OAM MUST support inter-working between the Network OAM and 370 Service OAM mechanisms. EVPN OAM MAY support inter-working among 371 other OAM layers. 373 3. EVPN OAM Requirements 375 This section discusses the EVPN OAM requirements pertaining to Fault 376 Management and Performance Management. 378 3.1 Fault Management Requirements 380 3.1.1 Proactive Fault Management Functions 382 The network operator configures proactive fault management functions 383 to run periodically without a time bound. Certain actions, for 384 example protection switchover or alarm indication signaling, can be 385 associated with specific events, such as entering or clearing fault 386 states. 388 3.1.1.1 Fault Detection (Continuity Check) 390 Proactive fault detection is performed by periodically monitoring the 391 reachability between service endpoints, i.e., MEPs in a given MA, 392 through the exchange of Continuity Check messages. The reachability 393 between any two arbitrary MEPs may be monitored for: 395 - in-band per-flow monitoring. This enables per flow monitoring 396 between MEPs. EVPN Network OAM MUST support fault detection with 397 per user flow granularity. EVPN Service OAM MAY support fault 398 detection with per user flow granularity. 400 - a representative path. This enables liveness check of the nodes 401 hosting the MEPs assuming that the loss of continuity to the MEP is 402 interpreted as a failure of the hosting node. This, however, does 403 not conclusively indicate liveness of the path(s) taken by user 404 data traffic. This enables node failure detection but not path 405 failure detection, through the use of a test flow. EVPN Network OAM 406 and Service OAM MUST support fault detection using test flows. 408 - all paths. For MPLS/IP networks with ECMP, monitoring of all 409 unicast paths between MEPs (on non-adjacent nodes) may not be 410 possible, since the per-hop ECMP hashing behavior may yield 411 situations where it is impossible for a MEP to pick flow entropy 412 characteristics that result in exercising the exhaustive set of 413 ECMP paths. Monitoring of all ECMP paths between MEPs (on non- 414 adjacent nodes) is not a requirement for EVPN OAM. 416 The fact that MPLS/IP networks do not enforce congruency between 417 unicast and multicast paths means that the proactive fault detection 418 mechanisms for EVPN networks MUST provide procedures to monitor the 419 unicast paths independently of the multicast paths. This applies to 420 EVPN Service OAM and Network OAM. 422 3.1.1.2 Defect Indication 424 EVPN Service OAM MUST support event-driven defect indication upon the 425 detection of a connectivity defect. Defect indications can be 426 categorized into two types: forward and reverse defect indications. 428 3.1.1.2.1 Forward Defect Indication 430 This is used to signal a failure that is detected by a lower layer 431 OAM mechanism. A server MEP (i.e. an actual or virtual MEP) transmits 432 a Forward Defect Indication in a direction that is away from the 433 direction of the failure (refer to Figure 3 below). 435 Failure 436 | 437 +-----+ +-----+ V +-----+ +-----+ 438 | A |------| B |--XXX--| C |------| D | 439 +-----+ +-----+ +-----+ +-----+ 441 <===========| |============> 442 Forward Forward 443 Defect Defect 444 Indication Indication 446 Figure 3: Forward Defect Indication 448 Forward defect indication may be used for alarm suppression and/or 449 for purpose of inter-working with other layer OAM protocols. Alarm 450 suppression is useful when a transport/network level fault translates 451 to multiple service or flow level faults. In such a scenario, it is 452 enough to alert a network management station (NMS) of the single 453 transport/network level fault in lieu of flooding that NMS with a 454 multitude of Service or Flow granularity alarms. EVPN PEs SHOULD 455 support Forward Defect Indication in the Service OAM mechanisms. 457 3.1.1.2.2 Reverse Defect Indication (RDI) 459 RDI is used to signal that the advertising MEP has detected a loss of 460 continuity (LoC) defect. RDI is transmitted in the direction of the 461 failure (refer to Figure 4). 463 Failure 464 | 465 +-----+ +-----+ V +-----+ +-----+ 466 | A |------| B |--XXX--| C |------| D | 467 +-----+ +-----+ +-----+ +-----+ 469 |===========> <============| 470 Reverse Reverse 471 Defect Defect 472 Indication Indication 474 Figure 4: Reverse Defect Indication 476 RDI allows single-sided management, where the network operator can 477 examine the state of a single MEP and deduce the overall health of a 478 monitored service. EVPN PEs SHOULD support Reverse Defect Indication 479 in the Service OAM mechanisms. This includes both the ability to 480 signal LoC defect to a remote MEP, as well as the ability to 481 recognize RDI from a remote MEP. Note that, in a multipoint MA, RDI 482 is not a useful indicator of unidirectional fault. This is because 483 RDI carries no indication of the affected MEP(s) with which the 484 sender had detected a LoC defect. 486 3.1.2 On-Demand Fault Management Functions 488 On-demand fault management functions are initiated manually by the 489 network operator and continue for a time bound period. These 490 functions enable the operator to run diagnostics to investigate a 491 defect condition. 493 3.1.2.1 Connectivity Verification 495 EVPN Network OAM MUST support on-demand connectivity verification 496 mechanisms for unicast and multicast destinations. The connectivity 497 verification mechanisms SHOULD provide a means for specifying and 498 carrying in the messages: 500 - variable length payload/padding to test MTU related connectivity 501 problems. 503 - test frame formats as defined in Appendix C of [RFC2544] to detect 504 potential packet corruption. 506 EVPN Network OAM MUST support connectivity verification at per flow 507 granularity. This includes both user flows (to test a specific path 508 between PEs) as well as test flows (to rest a representative path 509 between PEs). 511 EVPN Service OAM MUST support connectivity verification on test flows 512 and MAY support connectivity verification on user flows. 514 For multicast connectivity verification, EVPN Network OAM MUST 515 support reporting on: 517 - the DF filtering status of specific port(s) or all the ports in a 518 given bridge-domain. 520 - the Split Horizon filtering status of specific port(s) or all the 521 ports in a given bridge-domain. 523 3.1.2.2 Fault Isolation 525 EVPN OAM MUST support an on-demand fault localization function. This 526 involves the capability to narrow down the locality of a fault to a 527 particular port, link or node. The characteristic of forward/reverse 528 path asymmetry, in MPLS/IP, makes fault isolation a direction- 529 sensitive operation. That is, given two PEs A and B, localization of 530 continuity failures between them requires running fault isolation 531 procedures from PE A to PE B as well as from PE B to PE A. 533 EVPN Service OAM mechanisms only have visibility to the PEs but not 534 the MPLS/IP P nodes. As such, they can be used to deduce whether the 535 fault is in the customer's own network, the local CE-PE segment or 536 remote CE-PE segment(s). EVPN Network and Transport OAM mechanisms 537 can be used for fault isolation between the PEs and P nodes. 539 3.2 Performance Management 541 Performance Management functions can be performed both proactively 542 and on-demand. Proactive management involves a recurring function, 543 where the performance management probes are run continuously without 544 a trigger. We cover both proactive and on-demand functions in this 545 section. 547 3.2.1 Packet Loss 549 EVPN Network OAM SHOULD provide mechanisms for measuring packet loss 550 for a given service. 552 Given that EVPN provides inherent support for multipoint-to- 553 multipoint connectivity, then packet loss cannot be accurately 554 measured by means of counting user data packets. This is because user 555 packets can be delivered to more PEs or more ports than are necessary 556 (e.g. due to broadcast, un-pruned multicast or unknown unicast 557 flooding). As such, a statistical means of approximating packet loss 558 rate is required. This can be achieved by sending "synthetic" OAM 559 packets that are counted only by those ports (MEPs) that are required 560 to receive them. This provides a statistical approximation of the 561 number of data frames lost, even with multipoint-to-multipoint 562 connectivity. 564 3.2.2 Packet Delay 566 EVPN Service OAM SHOULD support measurement of one-way and two-way 567 packet delay and delay variation (jitter) across the EVPN network. 568 Measurement of one-way delay requires clock synchronization between 569 the probe source and target devices. Mechanisms for clock 570 synchronization are outside the scope of this document. Note that 571 Service OAM performance management mechanisms defined in [Y.1731] can 572 be used. 574 EVPN Network OAM MAY support measurement of one-way and two-way 575 packet delay and delay variation (jitter) across the EVPN network. 577 4. Security Considerations 579 EVPN OAM must provide mechanisms for: 581 - Preventing denial of service attacks caused by exploitation of the 582 OAM message channel. 584 - Optionally authenticate communicating endpoints (MEPs and MIPs). 586 - Preventing OAM packets from leaking outside of the EVPN network or 587 outside their corresponding Maintenance Domain. This can be done by 588 having MEPs implement a filtering function based on the Maintenance 589 Level associated with received OAM packets. 591 5. Acknowledgements 593 The authors would like to thank the following for their review of 594 this work and valuable comments: 596 Gregory Mirsky, Alexander Vainshtein 598 6. IANA Considerations 600 This document requires no IANA actions. 602 Normative References 604 [RFC792] Postel, J., "Internet Control Message Protocol", STD 5, RFC 605 792, DOI 10.17487/RFC0792, September 1981, 606 . 608 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 609 Requirement Levels", BCP 14, RFC 2119, DOI 610 10.17487/RFC2119, March 1997, . 613 [RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection 614 (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010, 615 . 617 [RFC5881] Katz, D. and D. Ward, "Bidirectional Forwarding Detection 618 (BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881, DOI 619 10.17487/RFC5881, June 2010, . 622 [RFC5883] Katz, D. and D. Ward, "Bidirectional Forwarding Detection 623 (BFD) for Multihop Paths", RFC 5883, DOI 10.17487/RFC5883, 624 June 2010, . 626 [RFC5884] Aggarwal, R., Kompella, K., Nadeau, T., and G. Swallow, 627 "Bidirectional Forwarding Detection (BFD) for MPLS Label 628 Switched Paths (LSPs)", RFC 5884, DOI 10.17487/RFC5884, 629 June 2010, .< 631 [RFC6291] Andersson, L., van Helvoort, H., Bonica, R., Romascanu, D., 632 and S. Mansfield, "Guidelines for the Use of the "OAM" 633 Acronym in the IETF", BCP 161, RFC 6291, DOI 634 10.17487/RFC6291, June 2011, . 637 [RFC6425] Saxena, S., Ed., Swallow, G., Ali, Z., Farrel, A., 638 Yasukawa, S., and T. Nadeau, "Detecting Data-Plane Failures 639 in Point-to-Multipoint MPLS - Extensions to LSP Ping", RFC 640 6425, DOI 10.17487/RFC6425, November 2011, 641 . 643 [RFC6428] Allan, D., Ed., Swallow, G., Ed., and J. Drake, Ed., 644 "Proactive Connectivity Verification, Continuity Check, and 645 Remote Defect Indication for the MPLS Transport Profile", 646 RFC 6428, DOI 10.17487/RFC6428, November 2011, 647 . 649 [RFC7432] Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A., 650 Uttaro, J., Drake, J., and W. Henderickx, "BGP MPLS-Based 651 Ethernet VPN", RFC 7432, DOI 10.17487/RFC7432, February 652 2015, . 654 [RFC7623] Sajassi, A., Ed., Salam, S., Bitar, N., Isaac, A., and W. 655 Henderickx, "Provider Backbone Bridging Combined with 656 Ethernet VPN (PBB-EVPN)", RFC 7623, DOI 10.17487/RFC7623, 657 September 2015, . 659 [RFC8029] Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N., 660 Aldrin, S., and M. Chen, "Detecting Multiprotocol Label 661 Switched (MPLS) Data-Plane Failures", RFC 8029, DOI 662 10.17487/RFC8029, March 2017, . 665 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 666 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 667 2017, 669 Informative References 671 [802.1Q] "IEEE Standard for Local and metropolitan area networks - 672 Media Access Control (MAC) Bridges and Virtual Bridge Local 673 Area Networks", 2014. 675 [Y.1731] "ITU-T Recommendation Y.1731 (02/08) - OAM functions and 676 mechanisms for Ethernet based networks", February 2008. 678 [RFC2544] Bradner, S. and J. McQuaid, "Benchmarking Methodology for 679 Network Interconnect Devices", RFC 2544, DOI 680 10.17487/RFC2544, March 1999, . 683 [RFC5085] Nadeau, T., Ed., and C. Pignataro, Ed., "Pseudowire Virtual 684 Circuit Connectivity Verification (VCCV): A Control Channel 685 for Pseudowires", RFC 5085, DOI 10.17487/RFC5085, December 686 2007, . 688 [RFC6136] Sajassi, A., Ed., and D. Mohan, Ed., "Layer 2 Virtual 689 Private Network (L2VPN) Operations, Administration, and 690 Maintenance (OAM) Requirements and Framework", RFC 6136, 691 DOI 10.17487/RFC6136, March 2011, . 694 Authors' Addresses 696 Samer Salam 697 Cisco 699 Email: ssalam@cisco.com 701 Ali Sajassi 702 Cisco 703 170 West Tasman Drive 704 San Jose, CA 95134, USA 706 Email: sajassi@cisco.com 708 Sam Aldrin 709 Google, Inc. 710 1600 Amphitheatre Parkway 711 Mountain View, CA USA 713 Email: aldrin.ietf@gmail.com 715 John E. Drake 716 Juniper Networks 717 1194 N. Mathilda Ave. 718 Sunnyvale, CA 94089, USA 720 Email: jdrake@juniper.net 722 Donald E. Eastlake, 3rd 723 Futurewei Technologies 724 2386 Panoramic Cirlce 725 Apopka, FL 32703 USA 727 Tel: +1-508-333-2270 728 Email: d3e3e3@gmail.com