INTERNET-DRAFT                                              Sami Boutros
Intended Status: Standard Track                                   VMware

                                                             Ali Sajassi
                                                             Samer Salam
                                                           Cisco Systems

                                                              John Drake
                                                        Juniper Networks

                                                           Jeff Tantsura
                                                                Ericsson

                                                          Dirk Steinberg
                                                    Steinberg Consulting

                                                         Thomas Beckhaus
                                                        Deutsche Telecom

                                                              J. Rabadan
                                                          Alcatel-Lucent

Expires: April September 17, 2016                                 October 15, 2015                               March 16, 2016

                         VPWS support in EVPN
                   draft-ietf-bess-evpn-vpws-02.txt
                   draft-ietf-bess-evpn-vpws-03.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 single-segment and multi-segment PW signaling, and provides
   fast protection using data-plane prefix independent convergence upon
   node or link failure.

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
   provisions of BCP 78 and BCP 79.

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Copyright and License Notice

   Copyright (c) 2015 2016 IETF Trust and the persons identified as the
   document authors. All rights reserved.

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Table of Contents

   1  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.1  Terminology . . . . . . . . . . . . . . . . . . . . . . . .  5
     1.2 Requirements . . . . . . . . . . . . . . . . . . . . . . . .  6
   2 Service interface  . . . . . . . . . . . . . . . . . . . . . . .  6
     2.1 VLAN-Based Service Interface . . . . . . . . . . . . . . . .  6
     2.2 VLAN Bundle Service Interface  . . . . . . . . . . . . . . .  7
       2.2.1 Port-Based Service Interface . . . . . . . . . . . . . .  7
     2.3 VLAN-Aware Bundle Service Interface  . . . . . . . . . . . .  7
     2.4  Flexible CrossConnect Service . . . . . . . . . . . . . . .  7
   3. BGP Extensions  . . . . . . . . . . . . . . . . . . . . . . . .  8
     3.1 EVPN Layer 2 attributes extended community . . . . . . . . .  9
   4 Operation  . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
   5 EVPN Comparison to PW Signaling  . . . . . . . . . . . . . . . . 11 12
   6 ESI Bandwidth  . . . . . . . . . . . . . . . . . . . . . . . . . 12
   7 Failure Scenarios  . . . . . . . . . . . . . . . . . . . . . . . 12
     7.1 Single-Homed CEs . . . . . . . . . . . . . . . . . . . . . . 13
     7.2 Multi-Homed CEs  . . . . . . . . . . . . . . . . . . . . . . 13
   8 VPWS with multiple sites . . . . . . . . . . . . . . . . . . . . 13
   9 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 13
   10 Security Considerations . . . . . . . . . . . . . . . . . . . . 13
   11 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 13
   12 References  . . . . . . . . . . . . . . . . . . . . . . . . . . 13
     12.1 Normative References  . . . . . . . . . . . . . . . . . . . 13
     12.2  Informative References . . . . . . . . . . . . . . . . . . 13 14
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14

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 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 signaling single-segment and
   multi-segment PWs for p2p Ethernet services.

   [EVPN] has the ability to forward customer traffic to/from a given
   customer Attachment Circuit (AC), aka Ethernet Segment in EVPN
   terminology, 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 ESes. 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 AD routes is used; whereas, for more
   general VPWS, traffic forwarding capability of EVPN based on the
   exchange of a group of Ethernet AD routes (one Ethernet AD route per
   AC/segment) 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-EVI Ethernet AD route can be used
   in forwarding user traffic to the destination AC.

   Both services are supported by using the Ethernet A-D per EVI route
   which contains an Ethernet Segment Identifier, in which the customer
   ES is encoded, and an Ethernet Tag, in which the VPWS service
   instance identifier is encoded.  I.e., for both EPL and EVPL
   services, a specific VPWS service instance is identified by a pair of
   Ethernet A-D per EVI 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
   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 valid value.

   In terms of route advertisement and MPLS label lookup behavior, EVPN-
   VPWS resembles the vlan-aware bundle mode of [RFC 7432] such that
   when a PE advertises Ethernet A-D per EVI route, the VPWS service
   instance serves as a 24-bit normalized Ethernet tag ID. 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 MUST
   remain tagged with the originating VID and any VID translation is
   performed at the disposition PE. For EPL service, the Ethernet frames
   are transported as is and the tags are not altered.

   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 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.

   VPWS: Virtual private wire service.

   EVI: EVPN Instance.

   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".

1.2 Requirements

   1. EPL service access circuit maps to the whole Ethernet port.

   2. EVPL service access circuits are VLANs on single or double tagged
   trunk ports. Each VLAN individually will be considered to be an
   endpoint for an EVPL service, without any direct dependency on any
   other VLANs on the trunk. Other VLANs on the same trunk could also be
   used for EVPL services, but could also be associated with other
   services.

   3. If multiple VLANs on the same trunk are associated with EVPL
   services, the respective remote endpoints of these EVPLs could be
   dispersed across any number of PEs, i.e. different VLANs may lead to
   different destinations.

   4. The VLAN tag on the access trunk only has PE-local significance.
   The VLAN tag on the remote end could be different, and could also be
   double tagged when the other side is single tagged.

   5. Also, multiple EVPL service VLANs on the same trunk could belong
   to the same EVPN instance (EVI), or they could belong to different
   EVIs. This should be purely an administrative choice of the network
   operator.

   6. A given access trunk could have hundreds of EVPL services, and a
   given PE could have thousands of EVPLs configured. It must be
   possible to configure multiple EVPL services within the same EVI.

   7. Local access circuits configured to belong to a given EVPN
   instance could also belong to different physical access trunks.

   8. EPL-LAN and EVP-LAN are possible on the same system and also ESIs
   can be shared between EVPL and EVP-LANs.

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. (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 LSP 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 corss connect traffic from a
   group of VLANs on a specific port to the MPLS LSP. 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 6.2.

2.3 VLAN-Aware Bundle Service Interface

   Contrary to EVPN, in EVPN-VPWS this service interface maps to VLAN-based VLAN-
   based service interface (defined in section 6.1) and thus this
   service interface is not used in EVPN-
   VPWS. 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.

2.4  Flexible CrossConnect Service

   This service provides the ultimate flexibility at the expense of
   additional lookup. With this EVPN-VPWS service a large number of
   attachments circuits (ACs), each of which represented by either
   single VLAN tag or double VLAN tags (QinQ) across multiple endpoints,
   are multiplexed in a single EVPN-VPWS service instance. An endpoint
   can be a physical interface, VSI, an IP-VRF, a MAC-VRF, or any other
   endpoint where cross-connection of the associated AC is desired.
   Because in this service mode, aggregation is performed across
   multiple endpoints, besides MPLS label, an additional VLAN ID lookup
   (either single tag or double tag) needs to be performed at the
   disposition PE in order to identify the destination endpoint. One can
   think of this as, the EVPN label identifies a cross-connect table and
   then a single tag (or double tag) lookup is performed to identify the
   endpoint. Each cross-connect table has its own unique VLAN space
   which mean it can have upto 4K single-tag VLAN (or upto 16M double-tag double-
   tag VLANs). VLAN IDs can be overlap across different cross-connect
   tables but MUST be unique within a table.

   The EVPN label besides identifying the cross-connect table, also
   identifies the following types of VID look-ups: Single VID lookup:
   The disposition PE MUST support single VID lookup where upon outer-
   VID lookup, the destination end-point is identified. Double VID
   lookup: The disposition PE MUST support double VID lookup where upon
   outer most two VIDs lookup, the destination end-point is identified.

   Wildcard VID Lookup: The disposition PE MAY support special double
   VID lookup where the first VID is outer most VID and the 2nd VID is
   the wild card (*).

   If no entry is found upon the lookup, a counter per cross-connect
   table is incremented. Upon finding an entry and identifying the
   destination endpoint, the packet is forwarded to that destination
   endpoint. Any further tag manipulation such as re-write (single or
   double), addition, deletion (single or double) will be performed at
   the endpoint.

   On the imposition PE, by associating an attachment circuit to an
   EVPN-VPWS service instance ID, we basically associate that attachment
   circuit with the corresponding cross-connect table.

   Since VID lookup (single or double) needs to be performed at the
   disposition PE, then VID normalization MUST be performed prior to the
   MPLS encapsulation on the ingress PE. This requires that both
   imposition and disposition PE devices be capable of VLAN tag
   manipulation, such as re-write (single or double), addition, deletion
   (single or double),  at their endpoints (e.g., their physical
   interfaces).

3. BGP Extensions
   This document proposes the use of the Ethernet A-D per EVI route to
   signal VPWS services. The Ethernet Segment Identifier field is set to
   the customer ES and the Ethernet Tag ID 32-bit field is set to the
   24-bit VPWS service instance identifier.  For both EPL and EVPL
   services, for a given VPWS service instance the pair of PEs
   instantiating that VPWS service instance will each advertise an
   Ethernet A-D per EVI 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 Ethernet A-D per
   EVI 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 Ethernet A-D
   per EVI 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, to be
   included with Ethernet A-D per EVI route. This attribute is mandatory
   if multihoming is enabled.

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

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

     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.
            SHOULD be set to 1 for multihoming all active scenarios.

     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 [RFC 4448] MUST be present
            when sending EVPN packets to this PE.

   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 corresponding VPWS service instance.

   The usage of the Per ES Ethernet AD 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 single active scenario, a remote PE receiving P=1 from
   more than one PE will select only one 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.

   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.

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 -------------------->|

   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 Ethernet
   A-D per EVI 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. 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 Ethernet A-D per EVI route the
   ESI field is set to 0 and the Ethernet Tag field is set to the VPWS
   service instance identifier that identifies the EVPL or EPL service.

   For a multi-homed CE, in an advertised Ethernet A-D per EVI route the
   ESI field is set to the CE's ESI and the Ethernet Tag field 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 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
   field in an advertised Ethernet A-D per EVI route MUST either be
   unique across all ASs, or an ASBR needs to perform a translation when
   the Ethernet A-D per EVI route is re-advertised by the ASBR from one
   AS to the other AS.

   Ethernet A-D per ES route can be used for mass withdraw to withdraw
   all Ethernet A-D per EVI 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 local repair mechanisms not available in
   VPWS.

6 ESI Bandwidth

   The ESI Bandwidth will be encoded using the Link Bandwidth Extended
   community defined in [draft-ietf-idr-link-bandwidth] and associated
   with the Ethernet AD route used to realize the EVPL services.

   When a PE receives this attribute for a given EVPL it MUST request
   the required bandwidth from the PSN towards the other EVPL service
   destination PE originating the message. When resources are allocated
   from the PSN for a given EVPL service, then the PSN SHOULD account
   for the Bandwidth requested by this EVPL service.

   In the case where PSN resources are not available, the PE receiving
   this attribute MUST re-send its local Ethernet AD routes for this
   EVPL service with the ESI Bandwidth = All FFs to declare that the
   "PSN Resources Unavailable".

   The scope of the ESI Bandwidth is limited to only one Autonomous
   System.

7 Failure Scenarios

   On a link or port failure between the CE and the PE for both single
   and multi-homed CEs, the PE must withdraw all the associated Ethernet
   AD routes for the VPWS service instances on the failed port or link.

7.1 Single-Homed CEs

   Unlike [EVPN],  EVPN-VPWS uses Ethernet AD 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 Ethernet A-D routes.

7.2 Multi-Homed CEs

   For a faster convergence in multi-homed scenarios with either Single-
   Active Redundancy or All-active redundancy, mass withdraw technique
   as per [EVPN] baseline is used. A PE previously advertising an
   Ethernet A-D per ES 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

8 VPWS with multiple sites

   The VPWS among multiple sites (full mesh of P2P connections - one per
   pair of sites) that can be setup automatically without any explicit
   provisioning of P2P connections among the sites is outside the scope
   of this document.

9 Acknowledgements

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

10 Security Considerations

   This document does not introduce any additional security constraints.

11 IANA Considerations

   Allocation of Extended Community Type and Sub-Type for EVPN L2
   attributes.

12 References

12.1 Normative References

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

12.2  Informative References

   [RFC7209] A. Sajassi, R. Aggarwal et. al., "Requirements for Ethernet
   VPN".

   [RFC7432] A. Sajassi, R. Aggarwal et. al., "BGP MPLS Based Ethernet
   VPN".

   [PBB-EVPN] A. Sajassi et. al., "PBB-EVPN", draft-ietf-l2vpn-pbb-evpn-
   08.txt.

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

   [draft-ietf-idr-link-bandwidth] P. Mohapatra, R. Fernando, "BGP Link
   Bandwidth Extended Community", draft-ietf-idr-link-bandwidth-06.txt

Authors' Addresses

   Sami Boutros
   Cisco
   VMware, Inc.
   Email: sboutros@cisco.com 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
   Ericsson
   Email: jeff.tantsura@ericsson.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
   Alcatel-Lucent
   Email: jorge.rabadan@alcatel-lucent.com

   Ryan Bickhart
   Juniper Networks
   Email: rbickhart@juniper.net