Internet Engineering Task Force (IETF)                        A. Sajassi
Request for Comments: 7209                                         Cisco
Category: Informational                                      R. Aggarwal
ISSN: 2070-1721                                                   Arktan
                                                              J. Uttaro
                                                                   AT&T
                                                               N. Bitar
                                                                Verizon
                                                          W. Henderickx
                                                         Alcatel-Lucent
                                                               A. Isaac
                                                              Bloomberg
                                                               May 2014


                 Requirements for Ethernet VPN (EVPN)

Abstract

  The widespread adoption of Ethernet L2VPN services and the advent of
  new applications for the technology (e.g., data center interconnect)
  have culminated in a new set of requirements that are not readily
  addressable by the current Virtual Private LAN Service (VPLS)
  solution.  In particular, multihoming with all-active forwarding is
  not supported, and there's no existing solution to leverage
  Multipoint-to-Multipoint (MP2MP) Label Switched Paths (LSPs) for
  optimizing the delivery of multi-destination frames.  Furthermore,
  the provisioning of VPLS, even in the context of BGP-based auto-
  discovery, requires network operators to specify various network
  parameters on top of the access configuration.  This document
  specifies the requirements for an Ethernet VPN (EVPN) solution, which
  addresses the above issues.

Status of This Memo

  This document is not an Internet Standards Track specification; it is
  published for informational purposes.

  This document is a product of the Internet Engineering Task Force
  (IETF).  It represents the consensus of the IETF community.  It has
  received public review and has been approved for publication by the
  Internet Engineering Steering Group (IESG).  Not all documents
  approved by the IESG are a candidate for any level of Internet
  Standard; see Section 2 of RFC 5741.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  http://www.rfc-editor.org/info/rfc7209.



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Copyright Notice

  Copyright (c) 2014 IETF Trust and the persons identified as the
  document authors.  All rights reserved.

  This document is subject to BCP 78 and the IETF Trust's Legal
  Provisions Relating to IETF Documents
  (http://trustee.ietf.org/license-info) in effect on the date of
  publication of this document.  Please review these documents
  carefully, as they describe your rights and restrictions with respect
  to this document.  Code Components extracted from this document must
  include Simplified BSD License text as described in Section 4.e of
  the Trust Legal Provisions and are provided without warranty as
  described in the Simplified BSD License.

Table of Contents

  1. Introduction ....................................................3
  2. Specification of Requirements ...................................4
  3. Terminology .....................................................4
  4. Redundancy Requirements .........................................5
     4.1. Flow-Based Load Balancing ..................................5
     4.2. Flow-Based Multipathing ....................................6
     4.3. Geo-redundant PE Nodes .....................................7
     4.4. Optimal Traffic Forwarding .................................7
     4.5. Support for Flexible Redundancy Grouping ...................8
     4.6. Multihomed Network .........................................8
  5. Multicast Optimization Requirements .............................9
  6. Ease of Provisioning Requirements ...............................9
  7. New Service Interface Requirements .............................10
  8. Fast Convergence ...............................................12
  9. Flood Suppression ..............................................12
  10. Supporting Flexible VPN Topologies and Policies ...............12
  11. Security Considerations .......................................13
  12. Normative References ..........................................13
  13. Informative References ........................................14
  14. Contributors ..................................................15














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1.  Introduction

  Virtual Private LAN Service (VPLS), as defined in [RFC4664],
  [RFC4761], and [RFC4762], is a proven and widely deployed technology.
  However, the existing solution has a number of limitations when it
  comes to redundancy, multicast optimization, and provisioning
  simplicity.  Furthermore, new applications are driving several new
  requirements for other L2VPN services such as Ethernet Tree (E-Tree)
  and Virtual Private Wire Service (VPWS).

  In the area of multihoming, current VPLS can only support multihoming
  with the single-active redundancy mode (defined in Section 3), for
  example, as described in [VPLS-BGP-MH].  Flexible multihoming with
  all-active redundancy mode (defined in Section 3) cannot be supported
  by the current VPLS solution.

  In the area of multicast optimization, [RFC7117] describes how
  multicast LSPs can be used in conjunction with VPLS.  However, this
  solution is limited to Point-to-Multipoint (P2MP) LSPs, as there's no
  defined solution for leveraging Multipoint-to-Multipoint (MP2MP) LSPs
  with VPLS.

  In the area of provisioning simplicity, current VPLS does offer a
  mechanism for single-sided provisioning by relying on BGP-based
  service auto-discovery [RFC4761] [RFC6074].  This, however, still
  requires the operator to configure a number of network-side
  parameters on top of the access-side Ethernet configuration.

  In the area of data-center interconnect, applications are driving the
  need for new service interface types that are a hybrid combination of
  VLAN bundling and VLAN-based service interfaces.  These are referred
  to as "VLAN-aware bundling" service interfaces.

  Virtualization applications are also fueling an increase in the
  volume of MAC (Media Access Control) addresses that are to be handled
  by the network; this gives rise to the requirement for having the
  network reconvergence upon failure be independent of the number of
  MAC addresses learned by the Provider Edge (PE).

  There are requirements for minimizing the amount of flooding of
  multi-destination frames and localizing the flooding to the confines
  of a given site.

  There are also requirements for supporting flexible VPN topologies
  and policies beyond those currently covered by VPLS and Hierarchical
  VPLS (H-VPLS).





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  The focus of this document is on defining the requirements for a new
  solution, namely, Ethernet VPN (EVPN), which addresses the above
  issues.

  Section 4 discusses the redundancy requirements.  Section 5 describes
  the multicast optimization requirements.  Section 6 articulates the
  ease of provisioning requirements.  Section 7 focuses on the new
  service interface requirements.  Section 8 highlights the fast
  convergence requirements.  Section 9 describes the flood suppression
  requirement, and finally Section 10 discusses the requirements for
  supporting flexible VPN topologies and policies.

2.  Specification of Requirements

  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 [RFC2119].

  This document is not a protocol specification and the key words in
  this document are used for clarity and emphasis of requirements
  language.

3.  Terminology

  AS: Autonomous System

  CE: Customer Edge

  E-Tree: Ethernet Tree

  MAC address: Media Access Control address - referred to as MAC

  LSP: Label Switched Path

  PE: Provider Edge

  MP2MP: Multipoint to Multipoint

  VPLS: Virtual Private LAN Service

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






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  All-Active Redundancy Mode: When a device is multihomed to a group of
  two or more PEs and when all PEs in such redundancy group can forward
  traffic to/from the multihomed device or network for a given VLAN,
  such multihoming is referred to as "All-Active".

4.  Redundancy Requirements

4.1.  Flow-Based Load Balancing

  A common mechanism for multihoming a CE node to a set of PE nodes
  involves leveraging multi-chassis Ethernet link aggregation groups
  (LAGs) based on [802.1AX].  [PWE3-ICCP] describes one such scheme.
  In Ethernet link aggregation, the load-balancing algorithms by which
  a CE distributes traffic over the Attachment Circuits connecting to
  the PEs are quite flexible.  The only requirement is for the
  algorithm to ensure in-order frame delivery for a given traffic flow.
  In typical implementations, these algorithms involve selecting an
  outbound link within the bundle based on a hash function that
  identifies a flow based on one or more of the following fields:

  i.   Layer 2: Source MAC Address, Destination MAC Address, VLAN
  ii.  Layer 3: Source IP Address, Destination IP Address
  iii. Layer 4: UDP or TCP Source Port, Destination Port

  A key point to note here is that [802.1AX] does not define a standard
  load-balancing algorithm for Ethernet bundles, and, as such,
  different implementations behave differently.  As a matter of fact, a
  bundle operates correctly even in the presence of asymmetric load
  balancing over the links.  This being the case, the first requirement
  for all-active multihoming is the ability to accommodate flexible
  flow-based load balancing from the CE node based on L2, L3, and/or L4
  header fields.

  (R1a) A solution MUST be capable of supporting flexible flow-based
        load balancing from the CE as described above.

  (R1b) A solution MUST also be able to support flow-based load
        balancing of traffic destined to the CE, even when the CE is
        connected to more than one PE.  Thus, the solution MUST be able
        to exercise multiple links connected to the CE, irrespective of
        the number of PEs that the CE is connected to.

  It should be noted that when a CE is multihomed to several PEs, there
  could be multiple Equal-Cost Multipath (ECMP) paths from each remote
  PE to each multihoming PE.  Furthermore, for an all-active multihomed
  CE, a remote PE can choose any of the multihoming PEs for sending





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  traffic destined to the multihomed CE.  Therefore, when a solution
  supports all-active multihoming, it MUST exercise as many of these
  paths as possible for traffic destined to a multihomed CE.

  (R1c) A solution SHOULD support flow-based load balancing among PEs
        that are members of a redundancy group spanning multiple
        Autonomous Systems.

4.2.  Flow-Based Multipathing

  Any solution that meets the all-active redundancy mode (e.g., flow-
  based load balancing) described in Section 4.1, also needs to
  exercise multiple paths between a given pair of PEs.  For instance,
  if there are two or more LSPs between a remote PE and a pair of PEs
  in an all-active redundancy group, then the solution needs to be
  capable of load balancing traffic among those LSPs on a per-flow
  basis for traffic destined to the PEs in the redundancy group.
  Furthermore, if there are two or more ECMP paths between a remote PE
  and one of the PEs in the redundancy group, then the solution needs
  to leverage all the equal-cost LSPs.  For the latter, the solution
  can also leverage the load-balancing capabilities based on entropy
  labels [RFC6790].

  (R2a) A solution MUST be able to exercise all LSPs between a remote
        PE and all the PEs in the redundancy group with all-active
        multihoming.

  (R2b) A solution MUST be able to exercise all ECMP paths between a
        remote PE and any of the PEs in the redundancy group with all-
        active multihoming.

  For example, consider a scenario in which CE1 is multihomed to PE1
  and PE2, and CE2 is multihomed to PE3 and PE4 running in all-active
  redundancy mode.  Furthermore, consider that there exist three ECMP
  paths between any of the CE1's and CE2's multihomed PEs.  Traffic
  from CE1 to CE2 can be forwarded on twelve different paths over the
  MPLS/IP core as follows: CE1 load balances traffic to both PE1 and
  PE2.  Each of PE1 and PE2 have three ECMP paths to PE3 and PE4 for a
  total of twelve paths.  Finally, when traffic arrives at PE3 and PE4,
  it gets forwarded to CE2 over the Ethernet channel (aka link bundle).

  It is worth pointing out that flow-based multipathing complements
  flow-based load balancing described in the previous section.








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4.3.  Geo-redundant PE Nodes

  The PE nodes offering multihomed connectivity to a CE or access
  network may be situated in the same physical location (co-located),
  or may be spread geographically (e.g., in different Central Offices
  (COs) or Points of Presence (POPs)).  The latter is needed when
  offering a geo-redundant solution that ensures business continuity
  for critical applications in the case of power outages, natural
  disasters, etc.  An all-active multihoming mechanism needs to support
  both co-located as well as geo-redundant PE placement.  The latter
  scenario often means that requiring a dedicated link between the PEs,
  for the operation of the multihoming mechanism, is not appealing from
  a cost standpoint.  Furthermore, the IGP cost from remote PEs to the
  pair of PEs in the dual-homed setup cannot be assumed to be the same
  when those latter PEs are geo-redundant.

  (R3a) A solution MUST support all-active multihoming without the need
        for a dedicated control/data link among the PEs in the
        multihomed group.

  (R3b) A solution MUST support different IGP costs from a remote PE to
        each of the PEs in a multihomed group.

  (R3c) A solution MUST support multihoming across different IGP
        domains within the same Autonomous System.

  (R3d) A solution SHOULD support multihoming across multiple
        Autonomous Systems.

4.4.  Optimal Traffic Forwarding

  In a typical network, when considering a designated pair of PEs, it
  is common to find both single-homed as well as multihomed CEs being
  connected to those PEs.

  (R4)  An all-active multihoming solution SHOULD support optimal
        forwarding of unicast traffic for all the following scenarios.
        By "optimal forwarding", we mean that traffic will not be
        forwarded between PE devices that are members of a multihomed
        group unless the destination CE is attached to one of the
        multihoming PEs.

        i.   single-homed CE to multihomed CE
        ii.  multihomed CE to single-homed CE
        iii. multihomed CE to multihomed CE

  This is especially important in the case of geo-redundant PEs, where
  having traffic forwarded from one PE to another within the same



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  multihomed group introduces additional latency, on top of the
  inefficient use of the PE node's and core nodes' switching capacity.
  A multihomed group (also known as a multi-chassis LAG) is a group of
  PEs supporting a multihomed CE.

4.5.  Support for Flexible Redundancy Grouping

  (R5) In order to support flexible redundancy grouping, the
        multihoming mechanism SHOULD allow arbitrary grouping of PE
        nodes into redundancy groups where each redundancy group
        represents all multihomed devices/networks that share the same
        group of PEs.

  This is best explained with an example: consider three PE nodes --
  PE1, PE2, and PE3.  The multihoming mechanism MUST allow a given PE,
  say, PE1, to be part of multiple redundancy groups concurrently.  For
  example, there can be a group (PE1, PE2), a group (PE1, PE3), and
  another group (PE2, PE3) where CEs could be multihomed to any one of
  these three redundancy groups.

4.6.  Multihomed Network

  There are applications that require an Ethernet network, rather than
  a single device, to be multihomed to a group of PEs.  The Ethernet
  network would typically run a resiliency mechanism such as Multiple
  Spanning Tree Protocol [802.1Q] or Ethernet Ring Protection Switching
  [G.8032].  The PEs may or may not participate in the control protocol
  of the Ethernet network.  For a multihomed network running [802.1Q]
  or [G.8032], these protocols require that each VLAN to be active only
  on one of the multihomed links.

  (R6a) A solution MUST support multihomed network connectivity with
        single-active redundancy mode where all VLANs are active on one
        PE.

  (R6b) A solution MUST also support multihomed networks with single-
        active redundancy mode where disjoint VLAN sets are active on
        disparate PEs.

  (R6c) A solution SHOULD support single-active redundancy mode among
        PEs that are members of a redundancy group spanning multiple
        ASes.

  (R6d) A solution MAY support all-active redundancy mode for a
        multihomed network with MAC-based load balancing (i.e.,
        different MAC addresses on a VLAN are reachable via different
        PEs).




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5.  Multicast Optimization Requirements

  There are environments where the use of MP2MP LSPs may be desirable
  for optimizing multicast, broadcast, and unknown unicast traffic in
  order to reduce the amount of multicast states in the core routers.
  [RFC7117] precludes the use of MP2MP LSPs since current VPLS
  solutions require an egress PE to perform learning when it receives
  unknown unicast packets over an LSP.  This is challenging when MP2MP
  LSPs are used, as they do not have inherent mechanisms to identify
  the sender.  The use of MP2MP LSPs for multicast optimization becomes
  tractable if the need to identify the sender for performing learning
  is lifted.

  (R7a) A solution MUST be able to provide a mechanism that does not
        require MAC learning against MPLS LSPs when packets are
        received over a MP2MP LSP.

  (R7b) A solution SHOULD be able to provide procedures to use MP2MP
        LSPs for optimizing delivery of multicast, broadcast, and
        unknown unicast traffic.

6.  Ease of Provisioning Requirements

  As L2VPN technologies expand into enterprise deployments, ease of
  provisioning becomes paramount.  Even though current VPLS has an
  auto-discovery mechanism, which enables automated discovery of member
  PEs belonging to a given VPN instance over the MPLS/IP core network,
  further simplifications are required, as outlined below:

  (R8a) The solution MUST support auto-discovery of VPN member PEs over
        the MPLS/IP core network, similar to the VPLS auto-discovery
        mechanism described in [RFC4761] and [RFC6074].

  (R8b) The solution SHOULD support auto-discovery of PEs belonging to
        a given redundancy or multihomed group.

  (R8c) The solution SHOULD support auto-sensing of the site ID for a
        multihomed device or network and support auto-generation of the
        redundancy group ID based on the site ID.

  (R8d) The solution SHOULD support automated Designated Forwarder (DF)
        election among PEs participating in a redundancy (multihoming)
        group and be able to divide service instances (e.g., VLANs)
        among member PEs of the redundancy group.

  (R8e) For deployments where VLAN identifiers are global across the
        MPLS network (i.e., the network is limited to a maximum of 4K
        services), the PE devices SHOULD derive the MPLS-specific



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        attributes (e.g., VPN ID, BGP Route Target, etc.) from the VLAN
        identifier.  This way, it is sufficient for the network
        operator to configure the VLAN identifier(s) for the access
        circuit, and all the MPLS and BGP parameters required for
        setting up the service over the core network would be
        automatically derived without any need for explicit
        configuration.

  (R8f) Implementations SHOULD revert to using default values for
        parameters for which no new values are configured.

7.  New Service Interface Requirements

  [MEF] and [802.1Q] have the following services specified:

  -  Port mode: in this mode, all traffic on the port is mapped to a
     single bridge domain and a single corresponding L2VPN service
     instance.  Customer VLAN transparency is guaranteed end to end.

  -  VLAN mode: in this mode, each VLAN on the port is mapped to a
     unique bridge domain and corresponding L2VPN service instance.
     This mode allows for service multiplexing over the port and
     supports optional VLAN translation.

  -  VLAN bundling: in this mode, a group of VLANs on the port are
     collectively mapped to a unique bridge domain and corresponding
     L2VPN service instance.  Customer MAC addresses must be unique
     across all VLANs mapped to the same service instance.

  For each of the above services, a single bridge domain is assigned
  per service instance on the PE supporting the associated service.
  For example, in case of the port mode, a single bridge domain is
  assigned for all the ports belonging to that service instance,
  regardless of the number of VLANs coming through these ports.

  It is worth noting that the term 'bridge domain' as used above refers
  to a MAC forwarding table as defined in the IEEE bridge model and
  does not denote or imply any specific implementation.

  [RFC4762] defines two types of VPLS services based on "unqualified
  and qualified learning", which in turn maps to port mode and VLAN
  mode, respectively.

  (R9a) A solution MUST support the above three service types (port
        mode, VLAN mode, and VLAN bundling).






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  For hosted applications for data-center interconnect, network
  operators require the ability to extend Ethernet VLANs over a WAN
  using a single L2VPN instance while maintaining data-plane separation
  between the various VLANs associated with that instance.  This is
  referred to as 'VLAN-aware bundling service'.

  (R9b) A solution MAY support VLAN-aware bundling service.

  This gives rise to two new service interface types: VLAN-aware
  bundling without translation and VLAN-aware bundling with
  translation.

  The service interface for VLAN-aware bundling without translation has
  the following characteristics:

  -  The service interface provides bundling of customer VLANs into a
     single L2VPN service instance.

  -  The service interface guarantees customer VLAN transparency end to
     end.

  -  The service interface maintains data-plane separation between the
     customer VLANs (i.e., creates a dedicated bridge-domain per VLAN).

  In the special case of all-to-one bundling, the service interface
  must not assume any a priori knowledge of the customer VLANs.  In
  other words, the customer VLANs shall not be configured on the PE;
  rather, the interface is configured just like a port-based service.

  The service interface for VLAN-aware bundling with translation has
  the following characteristics:

  -  The service interface provides bundling of customer VLANs into a
     single L2VPN service instance.

  -  The service interface maintains data-plane separation between the
     customer VLANs (i.e., creates a dedicated bridge-domain per VLAN).

  -  The service interface supports customer VLAN ID translation to
     handle the scenario where different VLAN Identifiers (VIDs) are
     used on different interfaces to designate the same customer VLAN.

  The main difference, in terms of service-provider resource
  allocation, between these new service types and the previously
  defined three types is that the new services require several bridge
  domains to be allocated (one per customer VLAN) per L2VPN service
  instance as opposed to a single bridge domain per L2VPN service
  instance.



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8.  Fast Convergence

  (R10a) A solution MUST provide the ability to recover from PE-CE
         attachment circuit failures as well as PE node failure for the
         cases of both multihomed device and multihomed network.

  (R10b) The recovery mechanism(s) MUST provide convergence time that
         is independent of the number of MAC addresses learned by the
         PE.  This is particularly important in the context of
         virtualization applications, which are fueling an increase in
         the number of MAC addresses to be handled by the Layer 2
         network.

  (R10c) Furthermore, the recovery mechanism(s) SHOULD provide
         convergence time that is independent of the number of service
         instances associated with the attachment circuit or the PE.

9.  Flood Suppression

  (R11a) The solution SHOULD allow the network operator to choose
         whether unknown unicast frames are to be dropped or to be
         flooded.  This attribute needs to be configurable on a per-
         service-instance basis.

  (R11b) In addition, for the case where the solution is used for data-
         center interconnect, the solution SHOULD minimize the flooding
         of broadcast frames outside the confines of a given site.  Of
         particular interest is periodic Address Resolution Protocol
         (ARP) traffic.

  (R11c) Furthermore, the solution SHOULD eliminate any unnecessary
         flooding of unicast traffic upon topology changes, especially
         in the case of a multihomed site where the PEs have a priori
         knowledge of the backup paths for a given MAC address.

10.  Supporting Flexible VPN Topologies and Policies

  (R12a) A solution MUST be capable of supporting flexible VPN
         topologies that are not constrained by the underlying
         mechanisms of the solution.

  One example of this is E-Tree topology, where one or more sites in
  the VPN are roots and the others are leaves.  The roots are allowed
  to send traffic to other roots and to leaves, while leaves can
  communicate only with the roots.  The solution MUST provide the
  ability to support E-Tree topology.





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  (R12b) The solution MAY provide the ability to apply policies at the
         granularity of the MAC address to control which PEs in the VPN
         learn which MAC address and how a specific MAC address is
         forwarded.  It should be possible to apply policies to allow
         only some of the member PEs in the VPN to send or receive
         traffic for a particular MAC address.

  (R12c) A solution MUST be capable of supporting both inter-AS
         option-C and inter-AS option-B scenarios as described in
         [RFC4364].

11.  Security Considerations

  Any protocol extensions developed for the EVPN solution shall include
  the appropriate security analysis.  Besides the security requirements
  covered in [RFC4761] and [RFC4762] when MAC learning is performed in
  data-plane and in [RFC4364] when MAC learning is performed in control
  plane, the following additional requirements need to be covered.

  (R13) A solution MUST be capable of detecting and properly handling a
        situation where the same MAC address appears behind two
        different Ethernet segments (whether inadvertently or
        maliciously).

  (R14) A solution MUST be capable of associating a MAC address to a
        specific Ethernet segment (aka "sticky MAC") in order to help
        limit malicious traffic into a network for that MAC address.
        This capability can limit the appearance of spoofed MAC
        addresses on a network.  When this feature is enabled, the MAC
        mobility for such sticky MAC addresses are disallowed, and the
        traffic for such MAC addresses from any other Ethernet segment
        MUST be discarded.

12.  Normative References

  [802.1AX]  IEEE, "IEEE Standard for Local and metropolitan area
             networks - Link Aggregation", Std. 802.1AX-2008, IEEE
             Computer Society, November 2008.

  [802.1Q]   IEEE, "IEEE Standard for Local and metropolitan area
             networks - Virtual Bridged Local Area Networks", Std.
             802.1Q-2011, 2011.

  [G.8032]   ITU-T, "Ethernet ring protection switching", ITU-T
             Recommendation G.8032, February 2012.

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.



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RFC 7209              Requirements for Ethernet VPN             May 2014


  [RFC4364]  Bersani, F. and H. Tschofenig, "The EAP-PSK Protocol: A
             Pre-Shared Key Extensible Authentication Protocol (EAP)
             Method", RFC 4764, January 2007.

  [RFC4761]  Kompella, K., Ed., and Y. Rekhter, Ed., "Virtual Private
             LAN Service (VPLS) Using BGP for Auto-Discovery and
             Signaling", RFC 4761, January 2007.

  [RFC4762]  Lasserre, M., Ed., and V. Kompella, Ed., "Virtual Private
             LAN Service (VPLS) Using Label Distribution Protocol (LDP)
             Signaling", RFC 4762, January 2007.

  [RFC6074]  Rosen, E., Davie, B., Radoaca, V., and W. Luo,
             "Provisioning, Auto-Discovery, and Signaling in Layer 2
             Virtual Private Networks (L2VPNs)", RFC 6074, January
             2011.

13.  Informative References

  [VPLS-BGP-MH]
             Kothari, B., Kompella, K., Henderickx, W., Balue, F.,
             Uttaro, J., Palislamovic, S., and W. Lin, "BGP based
             Multi-homing in Virtual Private LAN Service", Work in
             Progress, July 2013.

  [PWE3-ICCP]
             Martini, L., Salam, S., Sajassi, A., and S. Matsushima,
             "Inter-Chassis Communication Protocol for L2VPN PE
             Redundancy", Work in Progress, March 2014.

  [MEF]      Metro Ethernet Forum, "Ethernet Service Definitions", MEF
             6.1 Technical Specification, April 2008.

  [RFC4664]  Andersson, L., Ed., and E. Rosen, Ed., "Framework for
             Layer 2 Virtual Private Networks (L2VPNs)", RFC 4664,
             September 2006.

  [RFC6790]  Kompella, K., Drake, J., Amante, S., Henderickx, W., and
             L. Yong, "The Use of Entropy Labels in MPLS Forwarding",
             RFC 6790, November 2012.

  [RFC7117]  Aggarwal, R., Ed., Kamite, Y., Fang, L., Rekhter, Y., and
             C. Kodeboniya, "Multicast in Virtual Private LAN Service
             (VPLS)", RFC 7117, February 2014.







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14.  Contributors

  Samer Salam, Cisco, [email protected]
  John Drake, Juniper, [email protected]
  Clarence Filsfils, Cisco, [email protected]

Authors' Addresses

  Ali Sajassi
  Cisco
  EMail: [email protected]


  Rahul Aggarwal
  Arktan
  EMail: [email protected]


  James Uttaro
  AT&T
  EMail: [email protected]


  Nabil Bitar
  Verizon Communications
  EMail: [email protected]


  Wim Henderickx
  Alcatel-Lucent
  EMail: [email protected]


  Aldrin Isaac
  Bloomberg
  EMail: [email protected]















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