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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) == Missing Reference: 'RFCXXXX' is mentioned on line 524, but not defined Summary: 0 errors (**), 0 flaws (~~), 2 warnings (==), 1 comment (--). 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 4 Ali Sajassi 5 Samer Salam 6 Cisco Systems 7 John Drake 8 Juniper Networks 9 Jeff Tantsura 10 Individual 11 Dirk Steinberg 12 Steinberg Consulting 13 Thomas Beckhaus 14 Deutsche Telecom 15 J. Rabadan 16 Nokia 18 Expires: January 6, 2017 July 5, 2016 20 VPWS support in EVPN 21 draft-ietf-bess-evpn-vpws-07.txt 23 Abstract 25 This document describes how EVPN can be used to support Virtual 26 Private Wire Service (VPWS) in MPLS/IP networks. EVPN enables the 27 following characteristics for VPWS: single-active as well as all- 28 active multi-homing with flow-based load-balancing, eliminates the 29 need for traditional way of PW signaling, and provides fast 30 protection convergence upon node or link failure. 32 Status of this Memo 34 This Internet-Draft is submitted to IETF in full conformance with the 35 provisions of BCP 78 and BCP 79. 37 Internet-Drafts are working documents of the Internet Engineering 38 Task Force (IETF), its areas, and its working groups. Note that 39 other groups may also distribute working documents as 40 Internet-Drafts. 42 Internet-Drafts are draft documents valid for a maximum of six months 43 and may be updated, replaced, or obsoleted by other documents at any 44 time. It is inappropriate to use Internet-Drafts as reference 45 material or to cite them other than as "work in progress." 47 The list of current Internet-Drafts can be accessed at 48 http://www.ietf.org/1id-abstracts.html 49 The list of Internet-Draft Shadow Directories can be accessed at 50 http://www.ietf.org/shadow.html 52 Copyright and License Notice 54 Copyright (c) 2016 IETF Trust and the persons identified as the 55 document authors. All rights reserved. 57 This document is subject to BCP 78 and the IETF Trust's Legal 58 Provisions Relating to IETF Documents 59 (http://trustee.ietf.org/license-info) in effect on the date of 60 publication of this document. Please review these documents 61 carefully, as they describe your rights and restrictions with respect 62 to this document. Code Components extracted from this document must 63 include Simplified BSD License text as described in Section 4.e of 64 the Trust Legal Provisions and are provided without warranty as 65 described in the Simplified BSD License. 67 Table of Contents 69 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 70 1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . 4 71 1.2 Requirements . . . . . . . . . . . . . . . . . . . . . . . . 5 72 2 Service interface . . . . . . . . . . . . . . . . . . . . . . . 6 73 2.1 VLAN-Based Service Interface . . . . . . . . . . . . . . . . 6 74 2.2 VLAN Bundle Service Interface . . . . . . . . . . . . . . . 6 75 2.2.1 Port-Based Service Interface . . . . . . . . . . . . . . 6 76 2.3 VLAN-Aware Bundle Service Interface . . . . . . . . . . . . 7 77 3. BGP Extensions . . . . . . . . . . . . . . . . . . . . . . . . 7 78 3.1 EVPN Layer 2 attributes extended community . . . . . . . . . 7 79 4 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 80 5 EVPN Comparison to PW Signaling . . . . . . . . . . . . . . . . 10 81 6 Failure Scenarios . . . . . . . . . . . . . . . . . . . . . . . 11 82 6.1 Single-Homed CEs . . . . . . . . . . . . . . . . . . . . . . 11 83 6.2 Multi-Homed CEs . . . . . . . . . . . . . . . . . . . . . . 11 84 7 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 11 85 8 Security Considerations . . . . . . . . . . . . . . . . . . . . 11 86 9 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 11 87 10 References . . . . . . . . . . . . . . . . . . . . . . . . . . 12 88 10.1 Normative References . . . . . . . . . . . . . . . . . . . 12 89 10.2 Informative References . . . . . . . . . . . . . . . . . . 12 90 Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 91 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 12 93 1 Introduction 95 This document describes how EVPN can be used to support Virtual 96 Private Wire Service (VPWS) in MPLS/IP networks. The use of EVPN 97 mechanisms for VPWS brings the benefits of EVPN to p2p services. 98 These benefits include single-active redundancy as well as all-active 99 redundancy with flow-based load-balancing. Furthermore, the use of 100 EVPN for VPWS eliminates the need for traditional way of PW signaling 101 for p2p Ethernet services, as described in section 4. 103 [RFC7432] has the ability to forward customer traffic to/from a given 104 customer Attachment Circuit (AC), without any MAC lookup. This 105 capability is ideal in providing p2p services (aka VPWS services). 106 [MEF] defines Ethernet Virtual Private Line (EVPL) service as p2p 107 service between a pair of ACs (designated by VLANs) and Ethernet 108 Private Line (EPL) service, in which all traffic flows are between a 109 single pair of ports, that in EVPN terminology would mean a single 110 pair of ESes. EVPL can be considered as a VPWS with only two ACs. In 111 delivering an EVPL service, the traffic forwarding capability of EVPN 112 based on the exchange of a pair of Ethernet AD routes is used; 113 whereas, for more general VPWS, traffic forwarding capability of EVPN 114 based on the exchange of a group of Ethernet AD routes (one Ethernet 115 AD route per AC/ES) is used. In a VPWS service, the traffic from an 116 originating Ethernet Segment can be forwarded only to a single 117 destination Ethernet Segment; hence, no MAC lookup is needed and the 118 MPLS label associated with the per-EVI Ethernet AD route can be used 119 in forwarding user traffic to the destination AC. 121 Both services are supported by using the per EVI Ethernet A-D route 122 which contains an Ethernet Segment Identifier, in which the customer 123 ES is encoded, and an Ethernet Tag, in which the VPWS service 124 instance identifier is encoded. I.e., for both EPL and EVPL 125 services, a specific VPWS service instance is identified by a pair of 126 per EVI Ethernet A-D routes which together identify the VPWS service 127 instance endpoints and the VPWS service instance. In the control 128 plane the VPWS service instance is identified using the VPWS service 129 instance identifiers advertised by each PE and in the data plane the 130 value of the MPLS label advertised by one PE is used by the other PE 131 to send traffic for that VPWS service instance. As with the Ethernet 132 Tag in standard EVPN, the VPWS service instance identifier has 133 uniqueness within an EVPN instance. 135 Unlike EVPN where Ethernet Tag ID in EVPN routes are set to zero for 136 Port-based, vlan-based, and vlan-bundle interface mode and it is set 137 to non-zero Ethernet tag ID for vlan-aware bundle mode, in EVPN-VPWS, 138 for all the four interface modes, Ethernet tag ID in the Ethernet A-D 139 route MUST be set to a valid value in all the service interface 140 types. 142 In terms of route advertisement and MPLS label lookup behavior, EVPN- 143 VPWS resembles the vlan-aware bundle mode of [RFC7432] such that when 144 a PE advertises per EVI Ethernet A-D route, the VPWS service instance 145 serves as a 24-bit normalized Ethernet tag ID. The value of the MPLS 146 label in this route represents both the EVI and the VPWS service 147 instance, so that upon receiving an MPLS encapsulated packet, the 148 disposition PE can identify the egress AC from the lookup of the MPLS 149 label alone and perform any required tag translation. For EVPL 150 service, the Ethernet frames transported over an MPLS/IP network 151 SHOULD remain tagged with the originating VID and any VID translation 152 is performed at the disposition PE. For EPL service, the Ethernet 153 frames are transported as is and the tags are not altered. 155 The MPLS label value in the Ethernet A-D route can be set to the VNI 156 for VxLAN encap, and this VNI may have a global scope or local scope 157 per PE and may also be made equal to the VPWS service instance 158 identifier set in the Ethernet A-D route. 160 The Ethernet Segment identifier encoded in the Ethernet A-D per EVI 161 route is not used to identify the service, however it can be used for 162 flow-based load-balancing and mass withdraw functions. 164 As with standard EVPN, the Ethernet A-D per ES route is used for fast 165 convergence upon link or node failure and the Ethernet Segment route 166 is used for auto-discovery of the PEs attached to a given multi-homed 167 CE and to synchronize state between them. 169 1.1 Terminology 171 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 172 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 173 document are to be interpreted as described in RFC 2119 [RFC2119]. 175 MAC: Media Access Control 177 MPLS: Multi Protocol Label Switching. 179 OAM: Operations, Administration and Maintenance. 181 PE: Provide Edge Node. 183 CE: Customer Edge device e.g., host or router or switch. 185 EVPL: Ethernet Virtual Private Line. 187 EPL: Ethernet Private Line. 189 EP-LAN: Ethernet Private LAN. 191 EVP-LAN: Ethernet Virtual Private LAN. 193 VPWS: Virtual Private Wire Service. 195 EVI: EVPN Instance. 197 ES: Ethernet Segment on a PE refer to the link attached to it, this 198 link can be part of a set of links attached to different PEs in multi 199 home cases, or could be a single link in single home cases. 201 Single-Active Mode: When a device or a network is multi-homed to two 202 or more PEs and when only a single PE in such redundancy group can 203 forward traffic to/from the multi-homed device or network for a given 204 VLAN, then such multi-homing or redundancy is referred to as "Single- 205 Active". 207 All-Active: When a device is multi-homed to two or more PEs and when 208 all PEs in such redundancy group can forward traffic to/from the 209 multi-homed device for a given VLAN, then such multi-homing or 210 redundancy is referred to as "All-Active". 212 1.2 Requirements 214 1. EPL service access circuit maps to the whole Ethernet port. 216 2. EVPL service access circuits are VLANs on single or double tagged 217 trunk ports. Each VLAN individually (or combination) 218 will be considered to be an endpoint for an EVPL service, without any 219 direct dependency on any other VLANs on the trunk. Other VLANs on the 220 same trunk could also be used for EVPL services, but could also be 221 associated with other services. 223 3. If multiple VLANs on the same trunk are associated with EVPL 224 services, the respective remote endpoints of these EVPLs could be 225 dispersed across any number of PEs, i.e. different VLANs may lead to 226 different destinations. 228 4. The VLAN tag on the access trunk only has PE-local significance. 229 The VLAN tag on the remote end could be different, and could also be 230 double tagged when the other side is single tagged. 232 5. Also, multiple EVPL service VLANs on the same trunk could belong 233 to the same EVPN instance (EVI), or they could belong to different 234 EVIs. This should be purely an administrative choice of the network 235 operator. 237 6. A given PE could have thousands of EVPLs configured. It must be 238 possible to configure multiple EVPL services within the same EVI. 240 7. Local access circuits configured to belong to a given EVPN 241 instance could also belong to different physical access trunks. 243 8. EP-LAN and EVP-LAN are possible on the same system and also ESIs 244 can be shared between EVPL and EVP-LANs. 246 2 Service interface 248 2.1 VLAN-Based Service Interface 250 With this service interface, a VPWS instance identifier corresponds 251 to only a single VLAN on a specific interface. Therefore, there is a 252 one-to-one mapping between a VID on this interface and the VPWS 253 service instance identifier. The PE provides the cross-connect 254 functionality between MPLS LSP identified by the VPWS service 255 instance identifier and a specific . If the VLAN is 256 represented by different VIDs on different PEs. (e.g., a different 257 VID per Ethernet segment per PE), then each PE needs to perform VID 258 translation for frames destined to its Ethernet segment. In such 259 scenarios, the Ethernet frames transported over an MPLS/IP network 260 SHOULD remain tagged with the originating VID, and a VID translation 261 MUST be supported in the data path and MUST be performed on the 262 disposition PE. 264 2.2 VLAN Bundle Service Interface 266 With this service interface, a VPWS service instance identifier 267 corresponds to multiple VLANs on a specific interface. The PE 268 provides the cross-connect functionality between MPLS label 269 identified by the VPWS service instance identifier and a group of 270 VLANs on a specific interface. For this service interface, each VLAN 271 is presented by a single VID which means no VLAN translation is 272 allowed. The receiving PE, can direct the traffic based on EVPN label 273 alone to a specific port. The transmitting PE can cross connect 274 traffic from a group of VLANs on a specific port to the MPLS label. 275 The MPLS-encapsulated frames MUST remain tagged with the originating 276 VID. 278 2.2.1 Port-Based Service Interface 280 This service interface is a special case of the VLAN bundle service 281 interface, where all of the VLANs on the port are mapped to the same 282 VPWS service instance identifier. The procedures are identical to 283 those described in Section 2.2. 285 2.3 VLAN-Aware Bundle Service Interface 287 Contrary to EVPN, in EVPN-VPWS this service interface maps to VLAN- 288 based service interface (defined in section 2.1) and thus this 289 service interface is not used in EVPN-VPWS. In other words, if one 290 tries to define data-plane and control plane behavior for this 291 service interface, he would realize that it is the same as that of 292 VLAN-based service. 294 3. BGP Extensions 296 This document proposes the use of the per EVI Ethernet A-D route to 297 signal VPWS services. The Ethernet Segment Identifier field is set to 298 the customer ES and the Ethernet Tag ID 32-bit field is set to the 299 24-bit VPWS service instance identifier. For both EPL and EVPL 300 services, for a given VPWS service instance the pair of PEs 301 instantiating that VPWS service instance will each advertise a per 302 EVI Ethernet A-D route with its VPWS service instance identifier and 303 will each be configured with the other PE's VPWS service instance 304 identifier. When each PE has received the other PE's per EVI Ethernet 305 A-D route the VPWS service instance is instantiated. It should be 306 noted that the same VPWS service instance identifier may be 307 configured on both PEs. 309 The Route-Target (RT) extended community with which the per EVI 310 Ethernet A-D route is tagged identifies the EVPN instance in which 311 the VPWS service instance is configured. It is the operator's choice 312 as to how many and which VPWS service instances are configured in a 313 given EVPN instance. However, a given EVPN instance MUST NOT be 314 configured with both VPWS service instances and standard EVPN multi- 315 point services. 317 3.1 EVPN Layer 2 attributes extended community 319 This draft proposes a new extended community, defined below, to be 320 included with the per EVI Ethernet A-D route. This attribute is 321 mandatory if multihoming is enabled. 323 +------------------------------------+ 324 | Type(0x06)/Sub-type(0x04)(2 octet)| 325 +------------------------------------+ 326 | Control Flags (2 octets) | 327 +------------------------------------+ 328 | L2 MTU (2 octets) | 329 +------------------------------------+ 330 | Reserved (2 octets) | 331 +------------------------------------+ 332 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 333 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 334 | MBZ |C|P|B| (MBZ = MUST Be Zero) 335 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 337 The following bits in the Control Flags are defined; the remaining 338 bits MUST be set to zero when sending and MUST be ignored when 339 receiving this community. 341 Name Meaning 343 P If set to 1 in multihoming single-active scenarios, it 344 indicates that the advertising PE is the Primary PE. 345 SHOULD be set to 1 for multihoming all-active scenarios. 347 B If set to 1 in multihoming single-active scenarios, it 348 indicates that the advertising PE is the Backup PE. 350 C If set to 1, a Control word [RFC4448] MUST be present 351 when sending EVPN packets to this PE. 353 A received L2 MTU=0 means no MTU checking against local MTU is 354 needed. A received non-zero MTU SHOULD be checked against local MTU 355 and if there is a mismatch, the local PE MUST NOT add the remote PE 356 as the EVPN destination for the corresponding VPWS service instance. 358 The usage of the Per ES Ethernet AD route is unchanged from its usage 359 in [RFC7432], i.e. the "Single-Active" bit in the flags of the ESI 360 Label extended community will indicate if single-active or all-active 361 redundancy is used for this ES. 363 In a multihoming all-active scenario, there is no DF election, and 364 all the PEs in the ES that are active and ready to forward traffic 365 to/from the CE will set the P bit to 1. A remote PE will do per-flow 366 load balancing to the PEs that send P=1 for the same Ethernet Tag and 367 ESI. 369 In multihoming single-active scenario, the DF election will determine 370 who the primary and the backup PEs are, and only those PEs will set 371 the P bit and B bit respectively. A remote PE will forward the 372 traffic to the primary PE and switch over to the backup PE as soon as 373 it receives an Ethernet A-D route withdrawal from the primary PE in 374 the Ethernet Segment. 376 In multihoming single-active scenario, during transient situations, a 377 remote PE receiving P=1 from more than one PE will select the last 378 advertising PE as the primary PE when forwarding traffic. A remote PE 379 receiving B=1 from more than one PE will select only one backup PE. A 380 remote PE MUST receive P=1 from at least one PE before forwarding 381 traffic. 383 As per [RFC6790], if a network uses entropy labels then the control 384 word (C bit set) SHOULD NOT be used when sending EVPN-encapsulated 385 packets over a P2P LSP. 387 4 Operation 389 The following figure shows an example of a P2P service deployed with 390 EVPN. 391 Ethernet Ethernet 392 Native |<--------- EVPN Instance ----------->| Native 393 Service | | Service 394 (AC) | |<-PSN1->| |<-PSN2->| | (AC) 395 | V V V V V V | 396 | +-----+ +-----+ +-----+ +-----+ | 397 +----+ | | PE1 |======|ASBR1|==|ASBR2|===| PE3 | | +----+ 398 | |-------+-----+ +-----+ +-----+ +-----+-------| | 399 | CE1| | | |CE2 | 400 | |-------+-----+ +-----+ +-----+ +-----+-------| | 401 +----+ | | PE2 |======|ASBR3|==|ASBR4|===| PE4 | | +----+ 402 ^ +-----+ +-----+ +-----+ +-----+ ^ 403 | Provider Edge 1 ^ Provider Edge 2 | 404 | | | 405 | | | 406 | EVPN Inter-provider point | 407 | | 408 |<---------------- Emulated Service -------------------->| 410 iBGP sessions are established between PE1, PE2, ASBR1 and ASBR3, 411 possibly via a BGP route-reflector. Similarly, iBGP sessions are 412 established between PE3, PE4, ASBR2 and ASBR4. eBGP sessions are 413 established among ASBR1, ASBR2, ASBR3, and ASBR4. 415 All PEs and ASBRs are enabled for the EVPN SAFI and exchange per EVI 416 Ethernet A-D routes, one route per VPWS service instance. For inter- 417 AS option B, the ASBRs re-advertise these routes with Next Hop 418 attribute set to their IP addresses. The link between the CE and the 419 PE is either a C-tagged or S-tagged interface, as described in 420 [802.1Q], that can carry a single VLAN tag or two nested VLAN tags 421 and it is configured as a trunk with multiple VLANs, one per VPWS 422 service instance. It should be noted that the VLAN ID used by the 423 customer at either end of a VPWS service instance to identify that 424 service instance may be different and EVPN doesn't perform that 425 translation between the two values. Rather, the MPLS label will 426 identify the VPWS service instance and if translation is needed, it 427 should be done by the Ethernet interface for each service. 429 For single-homed CE, in an advertised per EVI Ethernet A-D route the 430 ESI field is set to 0 and the Ethernet Tag field is set to the VPWS 431 service instance identifier that identifies the EVPL or EPL service. 433 For a multi-homed CE, in an advertised per EVI Ethernet A-D route the 434 ESI field is set to the CE's ESI and the Ethernet Tag field is set to 435 the VPWS service instance identifier, which MUST have the same value 436 on all PEs attached to that ES. This allows an ingress PE to perform 437 flow-based load-balancing of traffic flows to all of the PEs attached 438 to that ES. In all cases traffic follows the transport paths, which 439 may be asymmetric. 441 The VPWS service instance identifier encoded in the Ethernet Tag 442 field in an advertised per EVI Ethernet A-D route MUST either be 443 unique across all ASs, or an ASBR needs to perform a translation when 444 the per EVI Ethernet A-D route is re-advertised by the ASBR from one 445 AS to the other AS. 447 Per ES Ethernet A-D route can be used for mass withdraw to withdraw 448 all per EVI Ethernet A-D routes associated with the multi-home site 449 on a given PE. 451 5 EVPN Comparison to PW Signaling 453 In EVPN, service endpoint discovery and label signaling are done 454 concurrently using BGP. Whereas, with VPWS based on [RFC4448], label 455 signaling is done via LDP and service endpoint discovery is either 456 through manual provisioning or through BGP. 458 In existing implementation of VPWS using pseudowires(PWs), redundancy 459 is limited to single-active mode, while with EVPN implementation of 460 VPWS both single-active and all-active redundancy modes can be 461 supported. 463 In existing implementation with PWs, backup PWs are not used to carry 464 traffic, while with EVPN, traffic can be load-balanced among 465 different PEs multi-homed to a single CE. 467 Upon link or node failure, EVPN can trigger failover with the 468 withdrawal of a single BGP route per EVPL service or multiple EVPL 469 services, whereas with VPWS PW redundancy, the failover sequence 470 requires exchange of two control plane messages: one message to 471 deactivate the group of primary PWs and a second message to activate 472 the group of backup PWs associated with the access link. 474 Finally, EVPN may employ data plane egress link protection mechanisms 475 not available in VPWS. This can be done by the primary PE (on local 476 AC down) using the label advertised in the per EVI Ethernet A-D route 477 by the backup PE to encapsulate the traffic and direct it to backup 478 PE. 480 6 Failure Scenarios 482 On a link or port failure between the CE and the PE for both single 483 and multi-homed CEs, unlike [RFC7432] the PE must withdraw all the 484 associated Ethernet AD routes for the VPWS service instances on the 485 failed port or link. 487 6.1 Single-Homed CEs 489 Unlike [RFC7432], EVPN-VPWS uses Ethernet AD route advertisements 490 for single-homed Ethernet Segments. Therefore, upon a link/port 491 failure of this single-homed Ethernet Segment, the PE MUST withdraw 492 the associated per EVI Ethernet A-D routes. 494 6.2 Multi-Homed CEs 496 For a faster convergence in multi-homed scenarios with either Single- 497 Active Redundancy or All-active redundancy, mass withdraw technique 498 as per [RFC7432] baseline is used. A PE previously advertising a per 499 ES Ethernet A-D route, can withdraw this route signaling to the 500 remote PEs to switch all the VPWS service instances associated with 501 this multi-homed ES to the backup PE 503 7 Acknowledgements 505 The authors would like to acknowledge Jeffrey Zhang, Wen Lin, Nitin 506 Singh, Senthil Sathappan and Vinod Prabhu for their feedback and 507 contributions to this document. 509 8 Security Considerations 511 The mechanisms in this document use EVPN control plane as defined in 512 [RFC7432]. Security considerations described in [RFC7432] are equally 513 applicable. 515 This document uses MPLS and IP-based tunnel technologies to support 516 data plane transport. Security considerations described in [RFC7432] 517 and in [ietf-evpn-overlay] are equally applicable. 519 9 IANA Considerations 521 IANA has allocated the following EVPN Extended Community sub-type: 523 SUB-TYPE VALUE NAME Reference 0x04 524 EVPN Layer 2 attributes [RFCXXXX] 526 10 References 528 10.1 Normative References 530 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 531 Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 532 1997, . 534 [RFC7432] Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A., 535 Uttaro, J., Drake, J., and W. Henderickx, "BGP MPLS-Based Ethernet 536 VPN", RFC 7432, DOI 10.17487/RFC7432, February 2015, . 539 [RFC4448] Martini, L., Rosen, E., El-Aawar, N., and G. Heron, 540 "Encapsulation Methods for Transport of Ethernet over MPLS Networks", 541 RFC 4448, April 2006. 543 [RFC6790] Kompella, K., Drake, J., Amante, S., Henderickx, W., and L. 544 Yong, "The Use of Entropy Labels in MPLS Forwarding", November 2012. 546 10.2 Informative References 548 [MEF] Metro Ethernet Forum, "Ethernet Services Definitions - Phase 549 2", Technical Specification MEF 6.1, April 2008, 550 . 553 Contributors 555 In addition to the authors listed on the front page, the following 556 co-authors have also contributed to this document: 558 Daniel Voyer Bell Canada 560 Authors' Addresses 562 Sami Boutros 563 VMware, Inc. 564 Email: sboutros@vmware.com 566 Ali Sajassi 567 Cisco 568 Email: sajassi@cisco.com 570 Samer Salam 571 Cisco 572 Email: ssalam@cisco.com 574 John Drake 575 Juniper Networks 576 Email: jdrake@juniper.net 578 Jeff Tantsura 579 Individual 580 Email: jefftant@gmail.com 582 Dirk Steinberg 583 Steinberg Consulting 584 Email: dws@steinbergnet.net 586 Patrice Brissette 587 Cisco 588 Email: pbrisset@cisco.com 590 Thomas Beckhaus 591 Deutsche Telecom 592 Email:Thomas.Beckhaus@telekom.de 594 Jorge Rabadan 595 Nokia 596 Email: jorge.rabadan@nokia.com 598 Ryan Bickhart 599 Juniper Networks 600 Email: rbickhart@juniper.net