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Please use uppercase 'NOT' together with RFC 2119 keywords (if that is what you mean). Found 'MUST not' in this paragraph: A received L2 MTU=0 means no MTU checking against local MTU is needed. A received non-zero MTU SHOULD be checked against local MTU and if there is a mismatch, the local PE MUST not add the remote PE as the EVPN destination for the corresponding VPWS service instance. == Using lowercase 'not' together with uppercase 'MUST', 'SHALL', 'SHOULD', or 'RECOMMENDED' is not an accepted usage according to RFC 2119. Please use uppercase 'NOT' together with RFC 2119 keywords (if that is what you mean). Found 'SHOULD not' in this paragraph: As per [RFC6790], if a network uses entropy labels then the control word (C bit set) SHOULD not be used when sending EVPN-encapsulated packets over a P2P LSP. -- The document date (June 6, 2016) is 2881 days in the past. Is this intentional? 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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 INTERNET-DRAFT Sami Boutros 3 Intended Status: Standard Track VMware 5 Ali Sajassi 6 Samer Salam 7 Cisco Systems 9 John Drake 10 Juniper Networks 12 Jeff Tantsura 13 Ericsson 15 Dirk Steinberg 16 Steinberg Consulting 18 Thomas Beckhaus 19 Deutsche Telecom 21 J. Rabadan 22 Nokia 24 Expires: December 8, 2016 June 6, 2016 26 VPWS support in EVPN 27 draft-ietf-bess-evpn-vpws-04.txt 29 Abstract 31 This document describes how EVPN can be used to support Virtual 32 Private Wire Service (VPWS) in MPLS/IP networks. EVPN enables the 33 following characteristics for VPWS: single-active as well as all- 34 active multi-homing with flow-based load-balancing, eliminates the 35 need for traditional way of PW signaling, and provides fast 36 protection convergence upon node or link failure. 38 Status of this Memo 40 This Internet-Draft is submitted to IETF in full conformance with the 41 provisions of BCP 78 and BCP 79. 43 Internet-Drafts are working documents of the Internet Engineering 44 Task Force (IETF), its areas, and its working groups. Note that 45 other groups may also distribute working documents as 46 Internet-Drafts. 48 Internet-Drafts are draft documents valid for a maximum of six months 49 and may be updated, replaced, or obsoleted by other documents at any 50 time. It is inappropriate to use Internet-Drafts as reference 51 material or to cite them other than as "work in progress." 53 The list of current Internet-Drafts can be accessed at 54 http://www.ietf.org/1id-abstracts.html 56 The list of Internet-Draft Shadow Directories can be accessed at 57 http://www.ietf.org/shadow.html 59 Copyright and License Notice 61 Copyright (c) 2016 IETF Trust and the persons identified as the 62 document authors. All rights reserved. 64 This document is subject to BCP 78 and the IETF Trust's Legal 65 Provisions Relating to IETF Documents 66 (http://trustee.ietf.org/license-info) in effect on the date of 67 publication of this document. Please review these documents 68 carefully, as they describe your rights and restrictions with respect 69 to this document. Code Components extracted from this document must 70 include Simplified BSD License text as described in Section 4.e of 71 the Trust Legal Provisions and are provided without warranty as 72 described in the Simplified BSD License. 74 Table of Contents 76 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 77 1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . 5 78 1.2 Requirements . . . . . . . . . . . . . . . . . . . . . . . . 6 79 2 Service interface . . . . . . . . . . . . . . . . . . . . . . . 7 80 2.1 VLAN-Based Service Interface . . . . . . . . . . . . . . . . 7 81 2.2 VLAN Bundle Service Interface . . . . . . . . . . . . . . . 7 82 2.2.1 Port-Based Service Interface . . . . . . . . . . . . . . 7 83 2.3 VLAN-Aware Bundle Service Interface . . . . . . . . . . . . 8 84 3. BGP Extensions . . . . . . . . . . . . . . . . . . . . . . . . 8 85 3.1 EVPN Layer 2 attributes extended community . . . . . . . . . 8 86 4 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 87 5 EVPN Comparison to PW Signaling . . . . . . . . . . . . . . . . 11 88 6 Failure Scenarios . . . . . . . . . . . . . . . . . . . . . . . 12 89 6.1 Single-Homed CEs . . . . . . . . . . . . . . . . . . . . . . 12 90 6.2 Multi-Homed CEs . . . . . . . . . . . . . . . . . . . . . . 12 91 7 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 12 92 8 Security Considerations . . . . . . . . . . . . . . . . . . . . 12 93 9 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 12 94 10 References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 95 10.1 Normative References . . . . . . . . . . . . . . . . . . . 13 96 10.2 Informative References . . . . . . . . . . . . . . . . . . 13 97 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13 99 1 Introduction 101 This document describes how EVPN can be used to support Virtual 102 Private Wire Service (VPWS) in MPLS/IP networks. The use of EVPN 103 mechanisms for VPWS brings the benefits of EVPN to p2p services. 104 These benefits include single-active redundancy as well as all-active 105 redundancy with flow-based load-balancing. Furthermore, the use of 106 EVPN for VPWS eliminates the need for traditional way of PW signaling 107 for p2p Ethernet services, as described in section 4. 109 [EVPN] has the ability to forward customer traffic to/from a given 110 customer Attachment Circuit (AC), without any MAC lookup. This 111 capability is ideal in providing p2p services (aka VPWS services). 112 [MEF] defines Ethernet Virtual Private Line (EVPL) service as p2p 113 service between a pair of ACs (designated by VLANs) and Ethernet 114 Private Line (EPL) service, in which all traffic flows are between a 115 single pair of ports, that in EVPN terminology would mean a single 116 pair of ESes. EVPL can be considered as a VPWS with only two ACs. In 117 delivering an EVPL service, the traffic forwarding capability of EVPN 118 based on the exchange of a pair of Ethernet AD routes is used; 119 whereas, for more general VPWS, traffic forwarding capability of EVPN 120 based on the exchange of a group of Ethernet AD routes (one Ethernet 121 AD route per AC/ES) is used. In a VPWS service, the traffic from an 122 originating Ethernet Segment can be forwarded only to a single 123 destination Ethernet Segment; hence, no MAC lookup is needed and the 124 MPLS label associated with the per-EVI Ethernet AD route can be used 125 in forwarding user traffic to the destination AC. 127 Both services are supported by using the per EVI Ethernet A-D route 128 which contains an Ethernet Segment Identifier, in which the customer 129 ES is encoded, and an Ethernet Tag, in which the VPWS service 130 instance identifier is encoded. I.e., for both EPL and EVPL 131 services, a specific VPWS service instance is identified by a pair of 132 per EVI Ethernet A-D routes which together identify the VPWS service 133 instance endpoints and the VPWS service instance. In the control 134 plane the VPWS service instance is identified using the VPWS service 135 instance identifiers advertised by each PE and in the data plane the 136 value of the MPLS label advertised by one PE is used by the other PE 137 to send traffic for that VPWS service instance. As with the Ethernet 138 Tag in standard EVPN, the VPWS service instance identifier has 139 uniqueness within an EVPN instance. 141 Unlike EVPN where Ethernet Tag ID in EVPN routes are set to zero for 142 Port-based, vlan-based, and vlan-bundle interface mode and it is set 143 to non-zero Ethernet tag ID for vlan-aware bundle mode, in EVPN-VPWS, 144 for all the four interface modes, Ethernet tag ID in the Ethernet A-D 145 route MUST be set to a valid value in all the service interface 146 types. 148 In terms of route advertisement and MPLS label lookup behavior, EVPN- 149 VPWS resembles the vlan-aware bundle mode of [RFC 7432] such that 150 when a PE advertises per EVI Ethernet A-D route, the VPWS service 151 instance serves as a 24-bit normalized Ethernet tag ID. The value of 152 the MPLS label in this route represents both the EVI and the VPWS 153 service instance, so that upon receiving an MPLS encapsulated packet, 154 the disposition PE can identify the egress AC from the lookup of the 155 MPLS label alone and perform any required tag translation. For EVPL 156 service, the Ethernet frames transported over an MPLS/IP network 157 SHOULD remain tagged with the originating VID and any VID translation 158 is performed at the disposition PE. For EPL service, the Ethernet 159 frames are transported as is and the tags are not altered. 161 The MPLS label value in the Ethernet A-D route can be set to the VNI 162 for VxLAN encap, and this VNI may have a global scope or local scope 163 per PE and may also be made equal to the VPWS service instance 164 identifier set in the Ethernet A-D route. 166 The Ethernet Segment identifier encoded in the Ethernet A-D per EVI 167 route is not used to identify the service, however it can be used for 168 flow-based load-balancing and mass withdraw functions. 170 As with standard EVPN, the Ethernet A-D per ES route is used for fast 171 convergence upon link or node failure and the Ethernet Segment route 172 is used for auto-discovery of the PEs attached to a given multi-homed 173 CE and to synchronize state between them. 175 1.1 Terminology 177 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 178 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 179 document are to be interpreted as described in RFC 2119 [RFC2119]. 181 MAC: Media Access Control 183 MPLS: Multi Protocol Label Switching. 185 OAM: Operations, Administration and Maintenance. 187 PE: Provide Edge Node. 189 CE: Customer Edge device e.g., host or router or switch. 191 EVPL: Ethernet Virtual Private Line. 193 EPL: Ethernet Private Line. 195 EP-LAN: Ethernet Private LAN. 197 EVP-LAN: Ethernet Virtual Private LAN. 199 VPWS: Virtual Private Wire Service. 201 EVI: EVPN Instance. 203 ES: Ethernet Segment on a PE refer to the link attached to it, this 204 link can be part of a set of links attached to different PEs in multi 205 home cases, or could be a single link in single home cases. 207 Single-Active Mode: When a device or a network is multi-homed to two 208 or more PEs and when only a single PE in such redundancy group can 209 forward traffic to/from the multi-homed device or network for a given 210 VLAN, then such multi-homing or redundancy is referred to as "Single- 211 Active". 213 All-Active: When a device is multi-homed to two or more PEs and when 214 all PEs in such redundancy group can forward traffic to/from the 215 multi-homed device for a given VLAN, then such multi-homing or 216 redundancy is referred to as "All-Active". 218 1.2 Requirements 220 1. EPL service access circuit maps to the whole Ethernet port. 222 2. EVPL service access circuits are VLANs on single or double tagged 223 trunk ports. Each VLAN individually (or combination) 224 will be considered to be an endpoint for an EVPL service, without any 225 direct dependency on any other VLANs on the trunk. Other VLANs on the 226 same trunk could also be used for EVPL services, but could also be 227 associated with other services. 229 3. If multiple VLANs on the same trunk are associated with EVPL 230 services, the respective remote endpoints of these EVPLs could be 231 dispersed across any number of PEs, i.e. different VLANs may lead to 232 different destinations. 234 4. The VLAN tag on the access trunk only has PE-local significance. 235 The VLAN tag on the remote end could be different, and could also be 236 double tagged when the other side is single tagged. 238 5. Also, multiple EVPL service VLANs on the same trunk could belong 239 to the same EVPN instance (EVI), or they could belong to different 240 EVIs. This should be purely an administrative choice of the network 241 operator. 243 6. A given PE could have thousands of EVPLs configured. It must be 244 possible to configure multiple EVPL services within the same EVI. 246 7. Local access circuits configured to belong to a given EVPN 247 instance could also belong to different physical access trunks. 249 8. EP-LAN and EVP-LAN are possible on the same system and also ESIs 250 can be shared between EVPL and EVP-LANs. 252 2 Service interface 254 2.1 VLAN-Based Service Interface 256 With this service interface, a VPWS instance identifier corresponds 257 to only a single VLAN on a specific interface. Therefore, there is a 258 one-to-one mapping between a VID on this interface and the VPWS 259 service instance identifier. The PE provides the cross-connect 260 functionality between MPLS LSP identified by the VPWS service 261 instance identifier and a specific . If the VLAN is 262 represented by different VIDs on different PEs. (e.g., a different 263 VID per Ethernet segment per PE), then each PE needs to perform VID 264 translation for frames destined to its Ethernet segment. In such 265 scenarios, the Ethernet frames transported over an MPLS/IP network 266 SHOULD remain tagged with the originating VID, and a VID translation 267 MUST be supported in the data path and MUST be performed on the 268 disposition PE. 270 2.2 VLAN Bundle Service Interface 272 With this service interface, a VPWS service instance identifier 273 corresponds to multiple VLANs on a specific interface. The PE 274 provides the cross-connect functionality between MPLS label 275 identified by the VPWS service instance identifier and a group of 276 VLANs on a specific interface. For this service interface, each VLAN 277 is presented by a single VID which means no VLAN translation is 278 allowed. The receiving PE, can direct the traffic based on EVPN label 279 alone to a specific port. The transmitting PE can cross connect 280 traffic from a group of VLANs on a specific port to the MPLS label. 281 The MPLS-encapsulated frames MUST remain tagged with the originating 282 VID. 284 2.2.1 Port-Based Service Interface 286 This service interface is a special case of the VLAN bundle service 287 interface, where all of the VLANs on the port are mapped to the same 288 VPWS service instance identifier. The procedures are identical to 289 those described in Section 2.2. 291 2.3 VLAN-Aware Bundle Service Interface 293 Contrary to EVPN, in EVPN-VPWS this service interface maps to VLAN- 294 based service interface (defined in section 2.1) and thus this 295 service interface is not used in EVPN-VPWS. In other words, if one 296 tries to define data-plane and control plane behavior for this 297 service interface, he would realize that it is the same as that of 298 VLAN-based service. 300 3. BGP Extensions 302 This document proposes the use of the per EVI Ethernet A-D route to 303 signal VPWS services. The Ethernet Segment Identifier field is set to 304 the customer ES and the Ethernet Tag ID 32-bit field is set to the 305 24-bit VPWS service instance identifier. For both EPL and EVPL 306 services, for a given VPWS service instance the pair of PEs 307 instantiating that VPWS service instance will each advertise a per 308 EVI Ethernet A-D route with its VPWS service instance identifier and 309 will each be configured with the other PE's VPWS service instance 310 identifier. When each PE has received the other PE's per EVI Ethernet 311 A-D route the VPWS service instance is instantiated. It should be 312 noted that the same VPWS service instance identifier may be 313 configured on both PEs. 315 The Route-Target (RT) extended community with which the per EVI 316 Ethernet A-D route is tagged identifies the EVPN instance in which 317 the VPWS service instance is configured. It is the operator's choice 318 as to how many and which VPWS service instances are configured in a 319 given EVPN instance. However, a given EVPN instance MUST NOT be 320 configured with both VPWS service instances and standard EVPN multi- 321 point services. 323 3.1 EVPN Layer 2 attributes extended community 325 This draft proposes a new extended community, defined below, to be 326 included with the per EVI Ethernet A-D route. This attribute is 327 mandatory if multihoming is enabled. 329 +------------------------------------+ 330 | Type(0x06)/Sub-type(0x04)(2 octet)| 331 +------------------------------------+ 332 | Control Flags (2 octets) | 333 +------------------------------------+ 334 | L2 MTU (2 octets) | 335 +------------------------------------+ 336 | Reserved (2 octets) | 337 +------------------------------------+ 338 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 339 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 340 | MBZ |C|P|B| (MBZ = MUST Be Zero) 341 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 343 The following bits in the Control Flags are defined; the remaining 344 bits MUST be set to zero when sending and MUST be ignored when 345 receiving this community. 347 Name Meaning 349 P If set to 1 in multihoming single-active scenarios, it 350 indicates that the advertising PE is the Primary PE. 351 SHOULD be set to 1 for multihoming all-active scenarios. 353 B If set to 1 in multihoming single-active scenarios, it 354 indicates that the advertising PE is the Backup PE. 356 C If set to 1, a Control word [RFC 4448] MUST be present 357 when sending EVPN packets to this PE. 359 A received L2 MTU=0 means no MTU checking against local MTU is 360 needed. A received non-zero MTU SHOULD be checked against local MTU 361 and if there is a mismatch, the local PE MUST not add the remote PE 362 as the EVPN destination for the corresponding VPWS service instance. 364 The usage of the Per ES Ethernet AD route is unchanged from its usage 365 in [RFC7432], i.e. the "Single-Active" bit in the flags of the ESI 366 Label extended community will indicate if single-active or all-active 367 redundancy is used for this ES. 369 In a multihoming all-active scenario, there is no DF election, and 370 all the PEs in the ES that are active and ready to forward traffic 371 to/from the CE will set the P bit to 1. A remote PE will do per-flow 372 load balancing to the PEs that send P=1 for the same Ethernet Tag and 373 ESI. 375 In multihoming single-active scenario, the DF election will determine 376 who the primary and the backup PEs are, and only those PEs will set 377 the P bit and B bit respectively. A remote PE will forward the 378 traffic to the primary PE and switch over to the backup PE as soon as 379 it receives an Ethernet A-D route withdrawal from the primary PE in 380 the Ethernet Segment. 382 In multihoming single-active scenario, during transient situations, a 383 remote PE receiving P=1 from more than one PE will select the last 384 advertising PE as the primary PE when forwarding traffic. A remote PE 385 receiving B=1 from more than one PE will select only one backup PE. A 386 remote PE MUST receive P=1 from at least one PE before forwarding 387 traffic. 389 As per [RFC6790], if a network uses entropy labels then the control 390 word (C bit set) SHOULD not be used when sending EVPN-encapsulated 391 packets over a P2P LSP. 393 4 Operation 395 The following figure shows an example of a P2P service deployed with 396 EVPN. 397 Ethernet Ethernet 398 Native |<--------- EVPN Instance ----------->| Native 399 Service | | Service 400 (AC) | |<-PSN1->| |<-PSN2->| | (AC) 401 | V V V V V V | 402 | +-----+ +-----+ +-----+ +-----+ | 403 +----+ | | PE1 |======|ASBR1|==|ASBR2|===| PE3 | | +----+ 404 | |-------+-----+ +-----+ +-----+ +-----+-------| | 405 | CE1| | | |CE2 | 406 | |-------+-----+ +-----+ +-----+ +-----+-------| | 407 +----+ | | PE2 |======|ASBR3|==|ASBR4|===| PE4 | | +----+ 408 ^ +-----+ +-----+ +-----+ +-----+ ^ 409 | Provider Edge 1 ^ Provider Edge 2 | 410 | | | 411 | | | 412 | EVPN Inter-provider point | 413 | | 414 |<---------------- Emulated Service -------------------->| 416 iBGP sessions are established between PE1, PE2, ASBR1 and ASBR3, 417 possibly via a BGP route-reflector. Similarly, iBGP sessions are 418 established between PE3, PE4, ASBR2 and ASBR4. eBGP sessions are 419 established among ASBR1, ASBR2, ASBR3, and ASBR4. 421 All PEs and ASBRs are enabled for the EVPN SAFI and exchange per EVI 422 Ethernet A-D routes, one route per VPWS service instance. For inter- 423 AS option B, the ASBRs re-advertise these routes with Next Hop 424 attribute set to their IP addresses. The link between the CE and the 425 PE is either a C-tagged or S-tagged interface, as described in 426 [802.1Q], that can carry a single VLAN tag or two nested VLAN tags 427 and it is configured as a trunk with multiple VLANs, one per VPWS 428 service instance. It should be noted that the VLAN ID used by the 429 customer at either end of a VPWS service instance to identify that 430 service instance may be different and EVPN doesn't perform that 431 translation between the two values. Rather, the MPLS label will 432 identify the VPWS service instance and if translation is needed, it 433 should be done by the Ethernet interface for each service. 435 For single-homed CE, in an advertised per EVI Ethernet A-D route the 436 ESI field is set to 0 and the Ethernet Tag field is set to the VPWS 437 service instance identifier that identifies the EVPL or EPL service. 439 For a multi-homed CE, in an advertised per EVI Ethernet A-D route the 440 ESI field is set to the CE's ESI and the Ethernet Tag field is set to 441 the VPWS service instance identifier, which MUST have the same value 442 on all PEs attached to that ES. This allows an ingress PE to perform 443 flow-based load-balancing of traffic flows to all of the PEs attached 444 to that ES. In all cases traffic follows the transport paths, which 445 may be asymmetric. 447 The VPWS service instance identifier encoded in the Ethernet Tag 448 field in an advertised per EVI Ethernet A-D route MUST either be 449 unique across all ASs, or an ASBR needs to perform a translation when 450 the per EVI Ethernet A-D route is re-advertised by the ASBR from one 451 AS to the other AS. 453 Per ES Ethernet A-D route can be used for mass withdraw to withdraw 454 all per EVI Ethernet A-D routes associated with the multi-home site 455 on a given PE. 457 5 EVPN Comparison to PW Signaling 459 In EVPN, service endpoint discovery and label signaling are done 460 concurrently using BGP. Whereas, with VPWS based on [RFC4448], label 461 signaling is done via LDP and service endpoint discovery is either 462 through manual provisioning or through BGP. 464 In existing implementation of VPWS using pseudowires(PWs), redundancy 465 is limited to single-active mode, while with EVPN implementation of 466 VPWS both single-active and all-active redundancy modes can be 467 supported. 469 In existing implementation with PWs, backup PWs are not used to carry 470 traffic, while with EVPN, traffic can be load-balanced among 471 different PEs multi-homed to a single CE. 473 Upon link or node failure, EVPN can trigger failover with the 474 withdrawal of a single BGP route per EVPL service or multiple EVPL 475 services, whereas with VPWS PW redundancy, the failover sequence 476 requires exchange of two control plane messages: one message to 477 deactivate the group of primary PWs and a second message to activate 478 the group of backup PWs associated with the access link. 480 Finally, EVPN may employ data plane egress link protection mechanisms 481 not available in VPWS. This can be done by the primary PE (on local 482 AC down) using the label advertised in the per EVI Ethernet A-D route 483 by the backup PE to encapsulate the traffic and direct it to backup 484 PE. 486 6 Failure Scenarios 488 On a link or port failure between the CE and the PE for both single 489 and multi-homed CEs, unlike [EVPN] the PE must withdraw all the 490 associated Ethernet AD routes for the VPWS service instances on the 491 failed port or link. 493 6.1 Single-Homed CEs 495 Unlike [EVPN], EVPN-VPWS uses Ethernet AD route advertisements for 496 single-homed Ethernet Segments. Therefore, upon a link/port failure 497 of this single-homed Ethernet Segment, the PE MUST withdraw the 498 associated per EVI Ethernet A-D routes. 500 6.2 Multi-Homed CEs 502 For a faster convergence in multi-homed scenarios with either Single- 503 Active Redundancy or All-active redundancy, mass withdraw technique 504 as per [EVPN] baseline is used. A PE previously advertising a per ES 505 Ethernet A-D route, can withdraw this route signaling to the remote 506 PEs to switch all the VPWS service instances associated with this 507 multi-homed ES to the backup PE 509 7 Acknowledgements 511 The authors would like to acknowledge Jeffrey Zhang, Wen Lin, Nitin 512 Singh, Senthil Sathappan and Vinod Prabhu for their feedback and 513 contributions to this document. 515 8 Security Considerations 517 The mechanisms in this document use EVPN control plane as defined in 518 [RFC7432]. Security considerations described in [RFC7432] are equally 519 applicable. 521 This document uses MPLS and IP-based tunnel technologies to support 522 data plane transport. Security considerations described in [RFC7432] 523 and in [ietf-evpn-overlay] are equally applicable. 525 9 IANA Considerations 527 IANA has allocated the following EVPN Extended Community sub-type in 529 [RFC7153]. 531 0x04 EVPN Layer 2 attributes [RFCXXXX] 533 10 References 535 10.1 Normative References 537 [KEYWORDS] Bradner, S., "Key words for use in RFCs to Indicate 538 Requirement Levels", BCP 14, RFC 2119, March 1997. 540 [RFC7432] A. Sajassi, R. Aggarwal et. al., "BGP MPLS Based Ethernet 541 VPN". 543 10.2 Informative References 545 [RFC7209] A. Sajassi, R. Aggarwal et. al., "Requirements for Ethernet 546 VPN". 548 [RFC7623] A. Sajassi et. al., "PBB-EVPN", "Provider Backbone Bridging 549 Combined with Ethernet VPN (PBB-EVPN)". 551 [RFC4761] Kompella, K. and Y. Rekhter, "Virtual Private LAN Service 552 (VPLS) Using BGP for Auto-Discovery and Signaling", RFC4761, January 553 2007. 555 Authors' Addresses 557 Sami Boutros 558 VMware, Inc. 559 Email: sboutros@vmware.com 561 Ali Sajassi 562 Cisco 563 Email: sajassi@cisco.com 565 Samer Salam 566 Cisco 567 Email: ssalam@cisco.com 569 John Drake 570 Juniper Networks 571 Email: jdrake@juniper.net 572 Jeff Tantsura 573 Ericsson 574 Email: jeff.tantsura@ericsson.com 576 Dirk Steinberg 577 Steinberg Consulting 578 Email: dws@steinbergnet.net 580 Patrice Brissette 581 Cisco 582 Email: pbrisset@cisco.com 584 Thomas Beckhaus 585 Deutsche Telecom 586 Email:Thomas.Beckhaus@telekom.de> 588 Jorge Rabadan 589 Alcatel-Lucent 590 Email: jorge.rabadan@alcatel-lucent.com 592 Ryan Bickhart 593 Juniper Networks 594 Email: rbickhart@juniper.net