INTERNET-DRAFT                                              Sami Boutros
Intended Status: Standard Track                                   VMware
                                                             Ali Sajassi
                                                             Samer Salam
                                                           Cisco Systems
                                                              John Drake
                                                        Juniper Networks
                                                              J. Rabadan
                                                                   Nokia

Expires: August 25, September 1, 2017                             February 21, 28, 2017

                         VPWS support in EVPN
                   draft-ietf-bess-evpn-vpws-09.txt
                   draft-ietf-bess-evpn-vpws-10.txt

Abstract

   This document describes how EVPN can be used to support Virtual
   Private Wire Service (VPWS) in MPLS/IP networks. EVPN enables the
   following characteristics for VPWS: single-active as well as all-
   active multi-homing with flow-based load-balancing, eliminates the
   need for traditional way of PW signaling, and provides fast
   protection convergence upon node or link failure.

Status of this Memo

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Table of Contents

   1  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1  Terminology . . . . . . . . . . . . . . . . . . . . . . . .  4
   2 Service interface  . . . . . . . . . . . . . . . . . . . . . . .  5
     2.1 VLAN-Based Service Interface . . . . . . . . . . . . . . . .  5
     2.2 VLAN Bundle Service Interface  . . . . . . . . . . . . . . .  6
       2.2.1 Port-Based Service Interface . . . . . . . . . . . . . .  6
     2.3 VLAN-Aware Bundle Service Interface  . . . . . . . . . . . .  6
   3. BGP Extensions  . . . . . . . . . . . . . . . . . . . . . . . .  6
     3.1 EVPN Layer 2 attributes extended community . . . . . . . . .  7
   4 Operation  . . . . . . . . . . . . . . . . . . . . . . . . . . .  9
   5 EVPN Comparison to PW Signaling  . . . . . . . . . . . . . . . . 10
   6 Failure Scenarios  . . . . . . . . . . . . . . . . . . . . . . . 11
     6.1 Single-Homed CEs . . . . . . . . . . . . . . . . . . . . . . 11
     6.2 Multi-Homed CEs  . . . . . . . . . . . . . . . . . . . . . . 11
   7 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 11
   8 Security Considerations  . . . . . . . . . . . . . . . . . . . . 11
   9 IANA Considerations  . . . . . . . . . . . . . . . . . . . . . . 11
   10 References  . . . . . . . . . . . . . . . . . . . . . . . . . . 12
     10.1 Normative References  . . . . . . . . . . . . . . . . . . . 12
     10.2  Informative References . . . . . . . . . . . . . . . . . . 12
   Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13

1  Introduction

   This document describes how EVPN can be used to support Virtual
   Private Wire Service (VPWS) in MPLS/IP networks. The use of EVPN
   mechanisms for VPWS (EVPN-VPWS) brings the benefits of EVPN to p2p
   services. These benefits include single-active redundancy as well as
   all-active redundancy with flow-based load-balancing. Furthermore,
   the use of EVPN for VPWS eliminates the need for traditional way of
   PW signaling for p2p Ethernet services, as described in section 4.

   [RFC7432] has the ability to forward customer traffic to/from a given
   customer Attachment Circuit (AC), without any MAC lookup. This
   capability is ideal in providing p2p services (aka VPWS services).
   [MEF] defines Ethernet Virtual Private Line (EVPL) service as p2p
   service between a pair of ACs (designated by VLANs) and Ethernet
   Private Line (EPL) service, in which all traffic flows are between a
   single pair of ports, that in EVPN terminology would mean a single
   pair of Ethernet Segments ES(es). EVPL can be considered as a VPWS
   with only two ACs. In delivering an EVPL service, the traffic
   forwarding capability of EVPN based on the exchange of a pair of
   Ethernet Auto-discovery (A-D) routes is used; whereas, for more
   general VPWS as per [RFC4664], traffic forwarding capability of EVPN
   based on the exchange of a group of Ethernet AD routes (one Ethernet
   AD route per AC/ES) is used. In a VPWS service,  the traffic from an
   originating Ethernet Segment can be forwarded only to a single
   destination Ethernet Segment; hence, no MAC lookup is needed and the
   MPLS label associated with the per EVPN instance (EVI) Ethernet A-D
   route can be used in forwarding user traffic to the destination AC.

   For both EPL and EVPL services, a specific VPWS service instance is
   identified by a pair of per EVI Ethernet A-D routes which together
   identify the VPWS service instance endpoints and the VPWS service
   instance. In the control plane the VPWS service instance is
   identified using the VPWS service instance identifiers advertised by
   each PE and in the data plane the value of the MPLS label advertised
   by one PE is used by the other PE to send traffic for that VPWS
   service instance. As with the Ethernet Tag in standard EVPN, the VPWS
   service instance identifier has uniqueness within an EVPN instance.

   Unlike EVPN where Ethernet Tag ID in EVPN routes are set to zero for
   Port-based, vlan-based, and vlan-bundle interface mode and it is set
   to non-zero Ethernet tag ID for vlan-aware bundle mode, in EVPN-VPWS,
   for all the four interface modes, Ethernet tag ID in the Ethernet A-D
   route MUST be set to a non-zero value in all the service interface
   types.

   In terms of route advertisement and MPLS label lookup behavior, EVPN-
   VPWS resembles the vlan-aware bundle mode of [RFC7432] such that when
   a PE advertises per EVI Ethernet A-D route, the VPWS service instance
   serves as a 32-bit normalized Ethernet tag ID. The value of the MPLS
   label in this route represents both the EVI and the VPWS service
   instance, so that upon receiving an MPLS encapsulated packet, the
   disposition PE can identify the egress AC from the lookup of the MPLS
   label alone and perform any required tag translation. For EVPL
   service, the Ethernet frames transported over an MPLS/IP network
   SHOULD remain tagged with the originating Vlan-ID (VID) and any VID
   translation MUST be performed at the disposition PE. For EPL service,
   the Ethernet frames are transported as is and the tags are not
   altered.

   The MPLS label value in the Ethernet A-D route can be set to the
   VXLAN Network Identifier (VNI) for VxLAN encap, and this VNI may have
   a global scope or local scope per PE and may also be made equal to
   the VPWS service instance identifier set in the Ethernet A-D route.

   The Ethernet Segment identifier encoded in the Ethernet A-D per EVI
   route is not used to identify the service, however it can be used for
   flow-based load-balancing and mass withdraw functions as per
   [RFC7432] baseline.

   As with standard EVPN, the Ethernet A-D per ES route is used for fast
   convergence upon link or node failure and the Ethernet Segment route
   is used for auto-discovery of the PEs attached to a given multi-homed
   CE and to synchronize state between them.

1.1  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

   MAC: Media Access Control

   MPLS: Multi Protocol Label Switching.

   OAM: Operations, Administration and Maintenance.

   PE: Provide Edge Node.

   CE: Customer Edge device e.g., host or router or switch.

   EVPL: Ethernet Virtual Private Line.

   EPL: Ethernet Private Line.

   EP-LAN: Ethernet Private LAN.

   EVP-LAN: Ethernet Virtual Private LAN.

   S-VLAN: Service VLAN identifier.

   C-VLAN: Customer VLAN identifier.

   VPWS: Virtual Private Wire Service.

   EVI: EVPN Instance.

   ES: Ethernet Segment on a PE refers to the link attached to it, this
   link can be part of a set of links attached to different PEs in multi
   homed cases, or could be a single link in single homed cases.

   ESI: Ethernet Segment Identifier.

   Single-Active Mode: When a device or a network is multi-homed to two
   or more PEs and when only a single PE in such redundancy group can
   forward traffic to/from the multi-homed device or network for a given
   VLAN, then such multi-homing or redundancy is referred to as "Single-
   Active".

   All-Active: When a device is multi-homed to two or more PEs and when
   all PEs in such redundancy group can forward traffic to/from the
   multi-homed device for a given VLAN, then such multi-homing or
   redundancy is referred to as "All-Active".

   VPWS Service Instance: It is represented by a pair of EVPN service
   labels associated with a pair of endpoints. Each label is downstream
   assigned and advertised by the disposition PE through an Ethernet A-D
   per-EVI route. The downstream label identifies the endpoint on the
   disposition PE. A VPWS service instance can be associated with only
   one VPWS service identifier.

2 Service interface

2.1 VLAN-Based Service Interface

   With this service interface, a VPWS instance identifier corresponds
   to only a single VLAN on a specific interface.  Therefore, there is a
   one-to-one mapping between a VID on this interface and the VPWS
   service instance identifier. The PE provides the cross-connect
   functionality between MPLS LSP identified by the VPWS service
   instance identifier and a specific <port,VLAN>. If the VLAN is
   represented by different VIDs on different PEs. PEs and different ES(es)
   (e.g., a different VID per Ethernet segment per PE), then each PE
   needs to perform VID translation for frames destined to its Ethernet
   segment.  In such scenarios, the Ethernet frames transported over an
   MPLS/IP network SHOULD remain tagged with the originating VID, and a
   VID translation MUST be supported in the data path and MUST be
   performed on the disposition PE.

2.2 VLAN Bundle Service Interface

   With this service interface, a VPWS service instance identifier
   corresponds to multiple VLANs on a specific interface. The PE
   provides the cross-connect functionality between MPLS label
   identified by the VPWS service instance identifier and a group of
   VLANs on a specific interface. For this service interface, each VLAN
   is presented by a single VID which means no VLAN translation is
   allowed. The receiving PE, can direct the traffic based on EVPN label
   alone to a specific port. The transmitting PE can cross connect
   traffic from a group of VLANs on a specific port to the MPLS label.
   The MPLS-encapsulated frames MUST remain tagged with the originating
   VID.

2.2.1 Port-Based Service Interface

   This service interface is a special case of the VLAN bundle service
   interface, where all of the VLANs on the port are mapped to the same
   VPWS service instance identifier.  The procedures are identical to
   those described in Section 2.2.

2.3 VLAN-Aware Bundle Service Interface

   Contrary to EVPN, in EVPN-VPWS this service interface maps to VLAN-
   based service interface (defined in section 2.1) and thus this
   service interface is not used in EVPN-VPWS.  In other words, if one
   tries to define data-plane and control plane behavior for this
   service interface, he would realize that it is the same as that of
   VLAN-based service.

3. BGP Extensions

   This document specifies the use of the per EVI Ethernet A-D route to
   signal VPWS services. The Ethernet Segment Identifier field is set to
   the customer ES and the Ethernet Tag ID 32-bit field MUST be set to
   the VPWS service instance identifier value. value, the VPWS service instance
   identifier value MAY be set to a 24-bit value, when 24-bit value is
   used, it MUST be right aligned. For both EPL and EVPL services, for a
   given VPWS service instance the pair of PEs instantiating that VPWS
   service instance will each advertise a per EVI Ethernet A-D route
   with its VPWS service instance identifier and will each be configured
   with the other PE's VPWS service instance identifier. When each PE
   has received the other PE's per EVI Ethernet A-D route the VPWS
   service instance is instantiated. It should be noted that the same
   VPWS service instance identifier may be configured on both PEs.

   The Route-Target (RT) extended community with which the per EVI
   Ethernet A-D route is tagged identifies the EVPN instance in which
   the VPWS service instance is configured. It is the operator's choice
   as to how many and which VPWS service instances are configured in a
   given EVPN instance. However, a given EVPN instance MUST NOT be
   configured with both VPWS service instances and standard EVPN multi-
   point services.

3.1 EVPN Layer 2 attributes extended community

   This draft proposes a new extended community, defined below as per
   [RFC7432] in addition to the values specified in community [RFC4360], to be
   included with the per EVI Ethernet A-D route. This attribute is
   mandatory if multihoming is enabled.

        +------------------------------------+
        |  Type(0x06)/Sub-type(0x04)(2 octet)|
        +------------------------------------+
        |  Control Flags  (2 octets)         |
        +------------------------------------+
        |  L2 MTU (2 octets)                 |
        +------------------------------------+
        |  Reserved (2 octets)               |
        +------------------------------------+

        Figure 1: EVPN Layer 2 attributes extended community

         0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        |   MBZ                   |C|P|B|  (MBZ = MUST Be Zero)
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        Figure 2: EVPN Layer 2 attributes Control Flags

     The following bits in the Control Flags are defined; the remaining
     bits MUST be set to zero when sending and MUST be ignored when
     receiving this community.

     Name   Meaning

     P      If set to 1 in multihoming single-active scenarios, it
            indicates that the advertising PE is the Primary PE.
            MUST be set to 1 for multihoming all-active scenarios by
            all active PE(s).

     B      If set to 1 in multihoming single-active scenarios, it
            indicates that the advertising PE is the Backup PE.

     C      If set to 1, a Control word [RFC4448] MUST be present
            when sending EVPN packets to this PE.

   L2 MTU (Maximum Transmission Unit) is a 2-octet value indicating the
   MTU in bytes.

   A received L2 MTU=0 means no MTU checking against local MTU is
   needed. A received non-zero MTU MUST 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.

   The usage of the Per ES Ethernet A-D route is unchanged from its
   usage in [RFC7432], i.e. the "Single-Active" bit in the flags of the
   ESI Label extended community will indicate if single-active or all-
   active redundancy is used for this ES.

   In multihoming scenarios, both B and P flags MUST NOT be both set. A
   PE that receives an update with both B and P flags set MUST treat the
   route as a withdrawal. If the PE receives a route with both B and P
   unset, it MUST discard the received route from the sender PE.

   In a multihoming all-active scenario, there is no DF election, and
   all the PEs in the ES that are active and ready to forward traffic
   to/from the CE will set the P Flag to 1. A remote PE will do per-flow
   load balancing to the PEs that send P=1 for the same Ethernet Tag and
   ESI. B Flag in control flags SHOULD NOT be set in the multihoming
   all-active scenario and MUST be ignored by receiving PE(s) if set.

   In multihoming single-active scenario, for a given VPWS service
   instance, in steady state, as result of DF election, the Primary
   elected PE for the VPWS service instance should signal P=1,B=0, the
   Backup elected PE should signal P=0,B=1, and the rest of the PEs in
   the same ES should signal P=0,B=0. When the primary PE/ES fails, the
   primary PE will withdraw the associated Ethernet A-D routes for the
   VPWS service instance from the remote PE, the remote PEs should then
   send traffic associated with the VPWS instance to the backup PE. DF
   re-election will happen between the PE(s) in the same ES, and there
   will be a new elected primary PE and new elected backup PE that will
   signal the P and B Flags as described. A remote PE SHOULD receive P=1
   from only one Primary PE and a B-1 B=1 from only one Backup PE. However
   during transient situations, a remote PE receiving P=1 from more than
   one PE will select the last advertising PE as the primary PE when
   forwarding traffic. A remote PE receiving B=1 from more than one PE
   will select only one backup PE. A remote PE MUST receive P=1 from at
   least one PE before forwarding traffic.

   If a network uses entropy labels per [RFC6790] then the C Flag MUST
   NOT be set to 1 and control word MUST NOT be used when sending EVPN-
   encapsulated packets over a P2P LSP.

4 Operation

   The following figure shows an example of a P2P service deployed with
   EVPN.
          Ethernet                                          Ethernet
          Native   |<--------- EVPN Instance ----------->|  Native
          Service  |                                     |  Service
           (AC)    |     |<-PSN1->|       |<-PSN2->|     |  (AC)
             |     V     V        V       V        V     V  |
             |     +-----+      +-----+  +-----+   +-----+  |
      +----+ |     | PE1 |======|ASBR1|==|ASBR2|===| PE3 |  |    +----+
      |    |-------+-----+      +-----+  +-----+   +-----+-------|    |
      | CE1| |                                              |    |CE2 |
      |    |-------+-----+      +-----+  +-----+   +-----+-------|    |
      +----+ |     | PE2 |======|ASBR3|==|ASBR4|===| PE4 |  |    +----+
           ^       +-----+      +-----+  +-----+   +-----+          ^
           |   Provider Edge 1        ^        Provider Edge 2      |
           |                          |                             |
           |                          |                             |
           |              EVPN Inter-provider point                 |
           |                                                        |
           |<---------------- Emulated Service -------------------->|

                    Figure 3: EVPN-VPWS Deployment Model
   iBGP sessions are established between PE1, PE2, ASBR1 and ASBR3,
   possibly via a BGP route-reflector. Similarly, iBGP sessions are
   established between PE3, PE4, ASBR2 and ASBR4. eBGP sessions are
   established among ASBR1, ASBR2, ASBR3, and ASBR4.

   All PEs and ASBRs are enabled for the EVPN SAFI and exchange per EVI
   Ethernet A-D routes, one route per VPWS service instance.  For inter-
   AS option B, the ASBRs re-advertise these routes with NEXT_HOP
   attribute set to their IP addresses as per [RFC4271]. The link
   between the CE and the PE is either a C-tagged or S-tagged interface,
   as described in [802.1Q], that can carry a single VLAN tag or two
   nested VLAN tags and it is configured as a trunk with multiple VLANs,
   one per VPWS service instance. It should be noted that the VLAN ID
   used by the customer at either end of a VPWS service instance to
   identify that service instance may be different and EVPN doesn't
   perform that translation between the two values. Rather, the MPLS
   label will identify the VPWS service instance and if translation is
   needed, it should be done by the Ethernet interface for each service.

   For single-homed CE, in an advertised per EVI Ethernet A-D route the
   ESI field is set to 0 and the Ethernet Tag ID is set to the VPWS
   service instance identifier that identifies the EVPL or EPL service.

   For a multi-homed CE, in an advertised per EVI Ethernet A-D route the
   ESI field is set to the CE's ESI and the Ethernet Tag ID is set to
   the VPWS service instance identifier, which MUST have the same value
   on all PEs attached to that ES. This allows an ingress PE in a
   multihoming all-active scenario to perform flow-based load-balancing
   of traffic flows to all of the PEs attached to that ES. In all cases
   traffic follows the transport paths, which may be asymmetric.

   The VPWS service instance identifier encoded in the Ethernet Tag ID
   in an advertised per EVI Ethernet A-D route MUST either be unique
   across all ASs, or an ASBR needs to perform a translation when the
   per EVI Ethernet A-D route is re-advertised by the ASBR from one AS
   to the other AS.

   Per ES Ethernet A-D route can be used for mass withdraw to withdraw
   all per EVI Ethernet A-D routes associated with the multi-home site
   on a given PE.

5 EVPN Comparison to PW Signaling

   In EVPN, service endpoint discovery and label signaling are done
   concurrently using BGP. Whereas, with VPWS based on [RFC4448], label
   signaling is done via LDP and service endpoint discovery is either
   through manual provisioning or through BGP.

   In existing implementation of VPWS using pseudowires(PWs), redundancy
   is limited to single-active mode, while with EVPN implementation of
   VPWS both single-active and all-active redundancy modes can be
   supported.

   In existing implementation with PWs, backup PWs are not used to carry
   traffic, while with EVPN, traffic can be load-balanced among
   different PEs multi-homed to a single CE.

   Upon link or node failure, EVPN can trigger failover with the
   withdrawal of a single BGP route per EVPL service or multiple EVPL
   services, whereas with VPWS PW redundancy, the failover sequence
   requires exchange of two control plane messages: one message to
   deactivate the group of primary PWs and a second message to activate
   the group of backup PWs associated with the access link.

   Finally, EVPN may employ data plane egress link protection mechanisms
   not available in VPWS. This can be done by the primary PE (on local
   AC down) using the label advertised in the per EVI Ethernet A-D route
   by the backup PE to encapsulate the traffic and direct it to backup
   PE.

6 Failure Scenarios

   On a link or port failure between the CE and the PE for both single
   and multi-homed CEs, unlike [RFC7432] the PE MUST withdraw all the
   associated Ethernet A-D routes for the VPWS service instances on the
   failed port or link.

6.1 Single-Homed CEs

   Unlike [RFC7432],  EVPN-VPWS uses Ethernet A-D route advertisements
   for single-homed Ethernet Segments. Therefore, upon a link/port
   failure of this single-homed Ethernet Segment, the PE MUST withdraw
   the associated per EVI Ethernet A-D routes.

6.2 Multi-Homed CEs

   For a faster convergence in multi-homed scenarios with either Single-
   Active Redundancy or All-active redundancy, mass withdraw technique
   is used. A PE previously advertising a per ES Ethernet A-D route, can
   withdraw this route signaling to the remote PEs to switch all the
   VPWS service instances associated with this multi-homed ES to the
   backup PE

7 Acknowledgements

   The authors would like to acknowledge Jeffrey Zhang, Wen Lin, Nitin
   Singh, Senthil Sathappan and Vinod Prabhu for their feedback and
   contributions to this document.

8 Security Considerations

   The mechanisms in this document use EVPN control plane as defined in
   [RFC7432]. Security considerations described in [RFC7432] are equally
   applicable.

   This document uses MPLS and IP-based tunnel technologies to support
   data plane transport. Security considerations described in [RFC7432]
   and in [ietf-evpn-overlay] are equally applicable.

9 IANA Considerations
   IANA has allocated the following EVPN Extended Community sub-type:
   SUB-TYPE VALUE     NAME                        Reference
         0x04         EVPN Layer 2 attributes     [RFCXXXX]

   This document creates a registry called "EVPN Layer 2 attributes
   Control Flags". New registrations will be made through the "RFC
   Required" procedure defined in [RFC5226].

   Initial registrations are as follows:

     P      Advertising PE is the Primary PE.
     B      Advertising PE is the Backup PE.
     C      Control word [RFC4448] MUST be present

10 References

10.1 Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
   Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March
   1997, <http://www.rfc-editor.org/info/rfc2119>.

   [RFC7432]  Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A.,
   Uttaro, J., Drake, J., and W. Henderickx, "BGP MPLS-Based Ethernet
   VPN", RFC 7432, DOI 10.17487/RFC7432, February 2015, <http://www.rfc-
   editor.org/info/rfc7432>.

   [RFC4448]  Martini, L., Rosen, E., El-Aawar, N., and G. Heron,
   "Encapsulation Methods for Transport of Ethernet over MPLS Networks",
   RFC 4448, April 2006.

   [RFC6790] Kompella, K., Drake, J., Amante, S., Henderickx, W., and L.
   Yong, "The Use of Entropy Labels in MPLS Forwarding", November 2012.

   [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A Border
   Gateway Protocol 4 (BGP-4)", RFC 4271, January 2006, <http://www.rfc-
   editor.org/info/rfc4271>.

   [RFC4360]  Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended
   Communities Attribute", RFC 4360, February 2006, <http://www.rfc-
   editor.org/info/rfc4360>.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
   IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008,
   <http://www.rfc-editor.org/info/rfc5226>.

10.2  Informative References

   [MEF] Metro Ethernet Forum, "Ethernet Services Definitions - Phase
   2", Technical Specification MEF 6.1, April 2008,
   https://urldefense.proofpoint.com/v2/url?u=https-
   3A__www.mef.net_Assets_Technical-5FSpecifications_PDF_MEF-
   5F6.1.pdf&d=DwIGaQ&c=uilaK90D4TOVoH58JNXRgQ&r=IVzcTRLQdpta08L0b_y2zDkqvwJhRKMCAbX-
   2K-LV98&m=GH5FIfqtBUACPwx-LVV2v5zPrGcNzhCEjfj8-0-
   R2OI&s=5b19ceQDqdsz0TepqsV7daJoYm9uDMyco7BZ4NeICWU&e=
   https://www.mef.net/Assets/Technical_Specifications/PDF/MEF_6.1.pdf

   [RFC4664]  Andersson, L., Ed., and E. Rosen, Ed., "Framework for
   Layer 2 Virtual Private Networks (L2VPNs)", RFC 4664, September 2006,
   <http://www.rfc-editor.org/info/rfc4664>.

   [ietf-evpn-overlay] Sajassi-Drake et al., "A Network Virtualization
   Overlay Solution using EVPN", draft-ietf-bess-evpn-overlay-07.txt,
   work in progress, December, 2016

Contributors

   In addition to the authors listed on the front page, the following
   co-authors have also contributed to this document:

   Daniel Voyer Bell Canada

Authors' Addresses

   Sami Boutros
   VMware, Inc.
   Email: sboutros@vmware.com

   Ali Sajassi
   Cisco
   Email: sajassi@cisco.com

   Samer Salam
   Cisco
   Email: ssalam@cisco.com

   John Drake
   Juniper Networks
   Email: jdrake@juniper.net

   Jeff Tantsura
   Individual
   Email: jefftant@gmail.com

   Dirk Steinberg
   Steinberg Consulting
   Email: dws@steinbergnet.net
   Patrice Brissette
   Cisco
   Email: pbrisset@cisco.com

   Thomas Beckhaus
   Deutsche Telecom
   Email: Thomas.Beckhaus@telekom.de

   Jorge Rabadan
   Nokia
   Email: jorge.rabadan@nokia.com

   Ryan Bickhart
   Juniper Networks
   Email: rbickhart@juniper.net