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Versions: 00 01 02 draft-ietf-lisp-eid-mobility

Network Working Group                                        M. Portoles
Internet-Draft                                             V. Ashtaputre
Intended status: Experimental                                  V. Moreno
Expires: April 11, 2017                                         F. Maino
                                                           Cisco Systems
                                                            D. Farinacci
                                                             lispers.net
                                                         October 8, 2016


         LISP L2/L3 EID Mobility Using a Unified Control Plane
                  draft-portoles-lisp-eid-mobility-01

Abstract

   The LISP control plane offers the flexibility to support multiple
   overlay flavors simultaneously.  This document specifies how LISP can
   be used to provide control-plane support to deploy a unified L2 and
   L3 overlay solution, as well as analyzing possible deployment options
   and models.

Requirements Language

   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].

Status of This Memo

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

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on April 11, 2017.








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Copyright Notice

   Copyright (c) 2016 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.  Definition of Terms . . . . . . . . . . . . . . . . . . . . .   4
   3.  Reference System  . . . . . . . . . . . . . . . . . . . . . .   4
   4.  L3 Overlays and Mobility Support  . . . . . . . . . . . . . .   5
     4.1.  Reference Architecture and packet flows . . . . . . . . .   5
       4.1.1.  Routed Traffic Flow: L3 Overlay use . . . . . . . . .   6
       4.1.2.  L3 Mobility Flow  . . . . . . . . . . . . . . . . . .   6
     4.2.  Implementation Considerations . . . . . . . . . . . . . .   7
       4.2.1.  L3 Segmentation . . . . . . . . . . . . . . . . . . .   7
       4.2.2.  L3 Database-Mappings  . . . . . . . . . . . . . . . .   8
       4.2.3.  LISP Mapping System support . . . . . . . . . . . . .   8
       4.2.4.  Using SMRs to Track Moved-Away Hosts  . . . . . . . .   9
       4.2.5.  L3 multicast support  . . . . . . . . . . . . . . . .   9
       4.2.6.  Time-to-Live Handling in Data-Plane . . . . . . . . .   9
   5.  L2 Overlays and Mobility Support  . . . . . . . . . . . . . .   9
     5.1.  Reference Architecture and packet flows . . . . . . . . .  10
       5.1.1.  Bridged Traffic Flow: L2 Overlay use  . . . . . . . .  10
       5.1.2.  L2 Mobility Flow  . . . . . . . . . . . . . . . . . .  11
     5.2.  Implementation Considerations . . . . . . . . . . . . . .  12
       5.2.1.  L2 Segmentation . . . . . . . . . . . . . . . . . . .  12
       5.2.2.  L2 Database-Mappings  . . . . . . . . . . . . . . . .  12
       5.2.3.  Interface to the LISP Mapping System  . . . . . . . .  13
       5.2.4.  SMR support to track L2 hosts that moved away . . . .  13
       5.2.5.  L2 Broadcast and Multicast traffic  . . . . . . . . .  14
       5.2.6.  L2 Unknown Unicast Support  . . . . . . . . . . . . .  14
       5.2.7.  Time-to-Live Handling in Data-Plane . . . . . . . . .  15
     5.3.  Support to ARP resolution through Mapping System  . . . .  15
       5.3.1.  Map-Server support to ARP resolution: Packet Flow . .  15
       5.3.2.  ARP registrations: MAC as a locator record  . . . . .  16
       5.3.3.  Implementation Considerations . . . . . . . . . . . .  18
   6.  Optional Deployment Models  . . . . . . . . . . . . . . . . .  19



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     6.1.  IP Forwarding of Intra-subnet Traffic . . . . . . . . . .  19
     6.2.  Data-plane Encapsulation Options  . . . . . . . . . . . .  20
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  21
   8.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  21
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  21
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  21
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  22
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  22

1.  Introduction

   This document describes the architecture and design options required
   to offer a unified L2 and L3 overlay solution with mobility using the
   LISP control-plane.

   The architecture takes advantage of the flexibility that LISP
   provides to simultaneously support different overlay types.  While
   the LISP specification defines both the data-plane and the control-
   plane, this document focuses on the use of the control-plane to
   provide L2 and L3 overlay services with mobility.  The control plane
   may be combined with a data-plane of choice e.g., [LISP], [VXLAN-
   GPE], or [VXLAN].

   The recommendation on whether a flow is sent over the L2 or the L3
   overlay is based on whether the traffic is bridged (intra-subnet or
   non-IP) or routed (inter-subnet), respectively.  This allows treating
   both overlays as separate segments, and enables L2-only and L3-only
   deployments (and combinations of them) without modifying the
   architecture.

   The unified solution for L2 and L3 overlays offers the possibility to
   extend subnets and routing domains (as required in state-of-art
   Datacenter and Enterprise architectures) with mobility support and
   traffic optimization.

   An important use-case of the unified architecture is that, while most
   data centers are complete layer-3 routing domains, legacy
   applications either have not converted to IP or still use auto-
   discovery at layer-2 and assume all nodes in an application cluster
   belong to the same subnet.  For these applications, the L2-overlay
   limits the functionality to where the legacy app lives versus having
   to extend layer-2 into the network.

   Broadcast, Unknown and Multicast traffic on the overlay are supported
   by either replicated unicast, or underlay (RLOC) multicast as
   specified in [RFC6831] and [I-D.ietf-lisp-signal-free-multicast].





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2.  Definition of Terms

   LISP related terms are defined as part of the LISP specification
   [RFC6830], notably EID, RLOC, Map-Request, Map- Reply, Map-Notify,
   Ingress Tunnel Router (ITR), Egress Tunnel Router (ETR), Map- Server
   (MS) and Map-Resolver (MR).

3.  Reference System

   The following figure illustrates the reference system used to support
   the packet flow description throughout this document.  The system
   presents 4 sites.  Site A and Site D provide access to different
   subnets (non-extended), while Site B and Site C extend a common
   subnet.  The xTR in each one of the sites registers EIDs from the
   sites with the LISP Mapping System and provides support to
   encapsulate overlay (EID) traffic through the underlay (RLOC space).

                            ,-------------.
                           (Mapping System )
                            -+------------+
                           +--+--+   +-+---+
                           |MS/MR|   |MS/MR|
                           +-+---+   +-----+
              .-._..-._.--._..|._.,.-._.,|-._.-_._.-.._.-.
          .-.'                                            '.-.
         (                    L3 Underlay                     )
          (                   (RLOC Space)                    )
          '.-._.'.-._.'--'._.'.-._.'.-._.'.-._.'.-._.'.-._.-.'
            /              |                 |               \
    RLOC=IP_A          RLOC=IP_B         RLOC=IP_C         RLOC=IP_D
    +-+--+--+          +-+--+--+         +-+--+--+         +-+--+--+
   .| xTR A |.-.      .| xTR B |.-.     .| xTR C |.-.     .| xTR D |.-.
  ( +-+--+--+   )    ( +-+--+--+   )   ( +-+--+--+   )   ( +-+--+--+   )
 .'   Site A   )   .'   Site B    )   .'   Site C   )   .'   Site D   )
 ( 1.0.0.0/24 .    ( 3.0.0.0/24  .    ( 3.0.0.0/24 .   (  2.0.0.0/24 .
 '--'._.'.     )    '--'._.'.     )    '--'._.'.    )   '--'._.'.     )
        /  '--'            |  '--'          |   '--'             \ '--'
    '--------'          '--------'        '--------'        '--------'
    :  End   :          :  End   :        :  End   :        :  End   :
    :Device 1:          :Device 2:        :Device 3:        :Device 4:
    '--------'          '--------'        '--------'        '--------'
    IP: 1.0.0.1         IP: 3.0.0.2       IP: 3.0.0.3       IP: 2.0.0.4
                     MAC: 0:0:3:0:0:2   MAC: 0:0:3:0:0:3

      Figure 1: Reference System Architecture with unified L2 and L3
                                 overlays





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   The recommended selection between the use of L2 and L3 overlays is to
   map them to bridged (intra-subnet or non-IP) and routed (inter-
   subnet) traffic.  The rest of the document follows this
   recommendation to describe the packet flows.

   However, note that in a different selection approach, intra-subnet
   traffic MAY also be sent over the L3 overlay.  Section 6.1 specifies
   the changes needed to send all IP traffic using the L3 overlay and
   restricting the use of the L2 overlay to non-IP traffic.

   When required, the control plane makes use of two basic types of EID-
   to-RLOC mappings associated to end-hosts and in order to support the
   unified architecture:

   o  EID = <IID, MAC> to RLOC=<IP>.  This is used to support the L2
      overlay.

   o  EID = <IID, IP> to RLOC=<IP>.  This is the traditional mapping as
      defined in the original LISP specification and supports the L3
      overlay.

4.  L3 Overlays and Mobility Support

4.1.  Reference Architecture and packet flows

   In order to support the packet flow descriptions in this section we
   use Figure 1 as reference.  This section uses Sites A and D to
   describe the flows.

           /              |                 |               \
   RLOC=IP_A          RLOC=IP_B         RLOC=IP_C         RLOC=IP_D
   +-+--+--+          +-+--+--+         +-+--+--+         +-+--+--+
  .| xTR A |.-.      .| xTR B |.-.     .| xTR C |.-.     .| xTR D |.-.
 ( +-+--+--+   )    ( +-+--+--+   )   ( +-+--+--+   )   ( +-+--+--+   )
.'   Site A   )   .'   Site B    )   .'   Site C   )   .'   Site D   )
( 1.0.0.0/24 .    ( 3.0.0.0/24  .    ( 3.0.0.0/24 .   (  2.0.0.0/24 .
'--'._.'.     )    '--'._.'.     )    '--'._.'.    )   '--'._.'.     )
       /  '--'            |  '--'          |   '--'             \ '--'
   '--------'          '--------'        '--------'        '--------'
   :  End   :          :  End   :        :  End   :        :  End   :
   :Device 1:          :Device 2:        :Device 3:        :Device 4:
   '--------'          '--------'        '--------'        '--------'
 (IID1,1.0.0.1)      (IID1,3.0.0.2)     (IID1,3.0.0.3)    (IID1,2.0.0.4)
                  (IID2,0:0:3:0:0:2)   (IID2,0:0:3:0:0:3)

                 Figure 2: Reference Mobility Architecture





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4.1.1.  Routed Traffic Flow: L3 Overlay use

   Inter-subnet traffic is encapsulated using the L3 overlay.  The
   process to encapsulate this traffic is the same as described in the
   original specification [RFC6830].  We describe the packet flow here
   for completeness

   The following is a sequence example of the unicast packet flow and
   the control plane operations when in the topology shown in Figure 1
   End-Device 1, in LISP site A, wants to communicate with End-Device 4
   in LISP site D.  Note that both end systems reside in different
   subnets.  We'll assume that End-Device 1 knows the EID IP address of
   End-Device 4 (e.g. it is learned using a DNS service).

   o  End-Device 1 sends an IP packet frame with destination 2.0.0.4 and
      source 1.0.0.1.  As the destination address lies on a different
      subnet End-Device 1 sends the packet following its routing table
      to ITR A (e.g., it is its default gateway).

   o  ITR A does a L3 lookup in its local map-cache for the destination
      IP 2.0.0.4.  When the lookup of 2.0.0.4 is a miss, the ITR sends a
      Map-request to the mapping database system looking up for
      EID=<IID1,2.0.0.4>.

   o  The mapping systems forwards the Map-Request to ETR D, that has
      registered the EID-to-RLOC mapping of EID=<IID1,2.0.0.4>.

   o  ETR D sends a Map-Reply to ITR A that includes the EID-to-RLOC
      mapping: EID=<IID1,2.0.0.4> -> RLOC=IP_D, where IP_D is the
      locator of ETR D.

   o  ITR A populates the local map-cache with the EID to RLOC mapping,
      and encapsulates all subsequent packets with a destination IP
      2.0.0.4 using destination RLOC=IP_D.

4.1.2.  L3 Mobility Flow

   The support to L3 mobility covers the requirements to allow an end-
   host to move from a given site to another and maintain correspondence
   with the rest of end-hosts that are connected to the same L3 routing
   domain.  This support MUST ensure convergence of L3 forwarding (IPv4/
   IPv6 based) from the old location to the new one when the host
   completes its move.

   The following is a sequence description of the packet flow when End-
   Device 1 in the reference figure roams to site D:





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   o  When End-Device 1 is attached or detected in site D, ETR D sets up
      the database mapping corresponding to EID=<IID1, 1.0.0.1>.  ETR D
      sends a Map-Register to the mapping system registering RLOC=IP_D
      as locator for EID=<IID1, 1.0.0.1>.  Now the mapping system is
      updated with the new EID-to-RLOC mapping (location) for End-Device
      1.

   o  The Mapping System, after receiving the new registration for
      EID=<IID1, 1.0.0.1> sends a Map-Notify to ETR A to inform it of
      the move.  Then, ETR A removes its local database mapping
      information and stops registering EID=<IID1, 1.0.0.1>.

   o  Any ITR or PiTR participating in the L3 overlay (corresponding to
      IID1) that were sending traffic to 1.0.0.1 before the migration
      keep sending traffic to ETR A.

   o  Once ETR A is notified by the Mapping system, when it receives
      traffic from an ITR with destination 1.0.0.1, it generates a
      Solicit-Map-Request (SMR) back to the ITR (or PiTR) for EID=<IID1,
      1.0.0.1>.

   o  Upon receiving the SMR the ITR invalidates its local map- cache
      entry for EID=<IID1, 1.0.0.1> and sends a new Map-Request for that
      EID.  The Map-Reply includes the new EID-to-RLOC mapping for End-
      Device 1 with RLOC=IP_D.

   o  Similarly, once the local database mapping is removed from ITR A,
      non-encapsulated packets arriving at ITR A from a local End-Device
      and destined to End-Device 1 result in a cache miss, which
      triggers sending a Map-Request for EID=<IID1, 1.0.0.1> to populate
      the map-cache of ITR A.

4.2.  Implementation Considerations

4.2.1.  L3 Segmentation

   LISP support of segmentation and multi-tenancy is structured around
   the propagation and use of Instance-IDs, and handled as part of the
   EID in control plane operations.  The encoding is described in
   [I-D.ietf-lisp-lcaf] and its use in [I-D.ietf-lisp-ddt].

   Instance-IDs can be used to support L3 overlay segmentation, such as
   in extended VRFs or multi-VPN overlays.








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4.2.2.  L3 Database-Mappings

   When an end-host is attached or detected in an ETR that provides
   L3-overlay services and mobility, a database Mapping is registered to
   the mapping system with the following structure:

   o  The EID 2-tuple (IID, IP) with its binding to a corresponding ETR
      locator set (IP RLOC)

   The registration of these EIDs MUST follow the LCAF format as defined
   in [I-D.ietf-lisp-lcaf] and the specific EID record to be used is
   illustrated in the following figure:

   +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   |                          Record TTL                           |
   |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   E   | Locator Count | EID mask-len  | ACT |A|      Reserved         |
   I   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   D   | Rsvd  |  Map-Version Number   |         AFI = 16387           |
   |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   r   |    Rsvd1     |     Flags      |   Type = 2    | IID mask-len  |
   e   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   c   |             4 + n             |        Instance-ID...         |
   o   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   r   |       ...Instance-ID          |        EID-AFI = 1 or 2       |
   d   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   |                    EID-Prefix (IPv4 or IPv6)                  |
   |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  /|    Priority   |    Weight     |  M Priority   |   M Weight    |
   | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | o |        Unused Flags     |L|p|R|           Loc-AFI             |
   | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  \|                             Locator                           |
   +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The L3 EID record follows the structure as described in [RFC6830].

4.2.3.  LISP Mapping System support

   The interface between the xTRs and the Mapping System is described in
   [RFC6833] and this document follows the specification as described
   there.  When available, the registrations MAY be implemented over a
   reliable transport as described in
   [I-D.kouvelas-lisp-map-server-reliable-transport].

   In order to support system convergence after mobility, when the Map-
   Server receives a new registration for a specific EID, it MUST send a
   Map-Notify to the entire RLOC set in the site that last registered



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   this same EID.  This Map-Notify is used to track moved-away state of
   L3 EIDs as described in Section 4.2.4.

4.2.4.  Using SMRs to Track Moved-Away Hosts

   One of the key elements to support end-host mobility using the LISP
   architecture is the Solicit-Map-Request (SMR).  This is a special
   message by means of which an ETR can request an ITR to send a new
   Map-Request for a particular EID record.  In essence the SMR message
   is used as a signal to indicate a change in mapping information and
   it is described with detail in [RFC6830].

   In order to support mobility, an ETR SHALL maintain a list of EID
   records for which it has to generate a SMR message whenever it
   receives traffic with that EID as destination.

   The particular strategy to maintain an Away Table is implementation
   specific and it will be typically based on the strategy to detect the
   presence of hosts and the use of Map-Notify messages received from
   the Map-Server.  In essence the table SHOULD provide support to the
   following:

   o  Keep track of end-hosts that were once connected to an ETR and
      have moved away.

   o  Support for L3 EID records, the 2-tuple (IID, IP), for which a SMR
      message SHOULD be generated.

4.2.5.  L3 multicast support

   L3 Multicast traffic on the overlay MAY be supported by either
   replicated unicast, or underlay (RLOC) multicast.  Specific solutions
   to support L3 multicast over LISP controlled overlays are specified
   in in [RFC6831], [I-D.ietf-lisp-signal-free-multicast] and
   [I-D.coras-lisp-re].

4.2.6.  Time-to-Live Handling in Data-Plane

   The LISP specification ([RFC6830]) describes how to handle Time-to-
   Live values of the inner and outer headers during encapsulation and
   decapsulation of packets when using the L3 overlay.

5.  L2 Overlays and Mobility Support








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5.1.  Reference Architecture and packet flows

   In order to support L2 packet flow descriptions in this section we
   use Figure 1 as reference.  This section uses Sites B and C to
   describe the flows.

           /              |                 |               \
   RLOC=IP_A          RLOC=IP_B         RLOC=IP_C         RLOC=IP_D
   +-+--+--+          +-+--+--+         +-+--+--+         +-+--+--+
  .| xTR A |.-.      .| xTR B |.-.     .| xTR C |.-.     .| xTR D |.-.
 ( +-+--+--+   )    ( +-+--+--+   )   ( +-+--+--+   )   ( +-+--+--+   )
.'   Site A   )   .'   Site B    )   .'   Site C   )   .'   Site D   )
( 1.0.0.0/24 .    ( 3.0.0.0/24  .    ( 3.0.0.0/24 .   (  2.0.0.0/24 .
'--'._.'.     )    '--'._.'.     )    '--'._.'.    )   '--'._.'.     )
       /  '--'            |  '--'          |   '--'             \ '--'
   '--------'          '--------'        '--------'        '--------'
   :  End   :          :  End   :        :  End   :        :  End   :
   :Device 1:          :Device 2:        :Device 3:        :Device 4:
   '--------'          '--------'        '--------'        '--------'
 (IID1,1.0.0.1)      (IID1,3.0.0.2)     (IID1,3.0.0.3)    (IID1,2.0.0.4)
                  (IID2,0:0:3:0:0:2)   (IID2,0:0:3:0:0:3)

                 Figure 3: Reference Mobility Architecture

5.1.1.  Bridged Traffic Flow: L2 Overlay use

   Bridged traffic is encapsulated using the L2 overlay.  This section
   provides an example of the unicast packet flow and the control plane
   operations when in the topology shown in Figure 1, the End-Device 2
   in site B communicates with the End-Device 3 in site C.  In this case
   we assume that End Device 2, knows the MAC address of End-Device 3
   (e.g., learned through ARP).

   o  End-Device 2 sends an Ethernet/IEEE 802 MAC frame with destination
      0:0:3:0:0:3 and source 0:0:3:0:0:2.

   o  ITR B does a L2 lookup in its local map-cache for the destination
      MAC 0:0:3:0:0:3.  When the lookup of 0:0:3:0:0:3 is a miss, the
      ITR sends a Map-Request to the mapping database system looking up
      for EID=<IID2,0:0:3:0:0:3>.

   o  The mapping systems forwards the Map-Request to ETR C, that has
      registered the EID-to-RLOC mapping for EID=<IID2,0:0:3:0:0:3>.
      Alternatively, depending on the mapping system configuration, a
      Map-Server which is part of the mapping database system MAY send a
      Map-Reply directly to ITR B.





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   o  ETR C sends a Map-Reply to ITR B that includes the EID-to-RLOC
      mapping: EID=<IID2, 0:0:3:0:0:3> -> RLOC=IP_C, where IP_C is the
      locator of ETR C.

   o  ITR B populates the local map-cache with the EID to RLOC mapping,
      and encapsulates all subsequent packets with a destination MAC
      0:0:3:0:0:3 using destination RLOC=IP_C.

5.1.2.  L2 Mobility Flow

   The support to L2 mobility covers the requirements to allow an end-
   host to move from a given site to another and maintain correspondence
   with the rest of end-hosts that are connected to the same L2 domain
   (e.g. extended VLAN).  This support MUST ensure convergence of L2
   forwarding (MAC based) from the old location to the new one, when the
   host completes its move.

   The following is a sequence description of the packet flow when End-
   Device 2 in the figure moves to Site C, which is extending its own
   subnet network.

   o  When End-Device 2 is attached or detected in site C, ETR C sets up
      the database mapping corresponding to EID=<IID2, 0:0:3:0:0:2>.
      ETR C sends a Map-Register to the mapping system registering
      RLOC=IP_B as locator for EID=<IID2, 0:0:3:0:0:2>.

   o  The Mapping System, after receiving the new registration for
      EID=<IID1, 0:0:3:0:0:2> sends a Map-Notify to ETR B with the new
      locator set (IP_B).  ETR B removes then its local database mapping
      and stops registering <IID2, 0:0:3:0:0:2>.

   o  Any PiTR or ITR participating in the same L2-overlay
      (corresponding to IID2) that was encapsulating traffic to
      0:0:3:0:0:2 before the migration continues encapsulating this
      traffic to ETR B.

   o  Once ETR B is notified by the Mapping system, when it receives
      traffic from an ITR which is destined to 0:0:3:0:0:2, it will
      generate a Solicit-Map-Request (SMR) message that is sent to the
      ITR for (IID2,0:0:3:0:0:2).

   o  Upon receiving the SMR the ITR sends a new Map-Request for the
      EID=<IID2,0:0:3:0:0:2>.  As a response ETR B sends a Map-Reply
      that includes the new EID-to-RLOC mapping for <IID2,0:0:3:0:0:2>
      with RLOC=IP_B.  This entry is cached in the L2 table of the ITR,
      replacing the previous one, and traffic is then forwarded to the
      new location.




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5.2.  Implementation Considerations

5.2.1.  L2 Segmentation

   As with L3 overlays, LISP support of L2 segmentation is structured
   around the propagation and use of Instance-IDs, and handled as part
   of the EID in control plane operations.  The encoding is described in
   [I-D.ietf-lisp-lcaf] and its use in [I-D.ietf-lisp-ddt].  Instance-
   IDs are unique to a Mapping System and MAY be used to identify the
   overlay type (e.g., L2 or L3 overlay).

   An Instance-ID can be used for L2 overlay segmentation.  An important
   aspect of L2 segmentation is the mapping of VLANs to IIDs.  In this
   case a Bridge Domain (which is the L2 equivalent to a VRF as a
   forwarding context) maps to an IID, a VLAN-ID may map 1:1 to a bridge
   domain or different VLAN-IDs on different ports may map to a common
   Bridge Domain, which in turn maps to an IID in the L2 overlay.  When
   ethernet traffic is double tagged, usually the outer 802.1Q tag will
   be mapped to a bridge domain on a per port basis, and the inner
   802.1Q tag will remain part of the payload to be handled by the
   overlay.  The IID should therefore be able to carry ethernet traffic
   with or without an 802.1Q header.  A port may also be configured as a
   trunk and we may chose to take the encapsulated traffic and map it to
   a single IID in order to multiplex traffic from multiple VLANs on a
   single IID.  These are all examples of local operations that could be
   effected on VLANs in order to map them to IIDs, they are provided as
   examples and are not exhaustive.

5.2.2.  L2 Database-Mappings

   When an end-host is attached or detected in an ETR that provides
   L2-overlay services, a database Mapping is registered to the mapping
   system with the following structure:

   o  The EID 2-tuple (IID, MAC) with its binding to a locator set (IP
      RLOC)

   The registration of these EIDs MUST follow the LCAF format as defined
   in [I-D.ietf-lisp-lcaf] and as illustrated in the following figure:












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   +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   |                          Record TTL                           |
   |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   E   | Locator Count | EID mask-len  | ACT |A|      Reserved         |
   I   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   D   | Rsvd  |  Map-Version Number   |         AFI = 16387           |
   |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   r   |    Rsvd1     |     Flags      |   Type = 2    | IID mask-len  |
   e   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   c   |             4 + n             |        Instance-ID...         |
   o   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   r   |       ...Instance-ID          |        EID-AFI = 6            |
   d   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   |                   Layer-2 MAC Address  ...                    |
   |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  /| ... Layer-2 MAC Address       |    Priority   |    Weight     |
   | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | o |  M Priority   |   M Weight    |        Unused Flags     |L|p|R|
   | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | | |           Loc-AFI             |     Locator....               |
   | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  \|       ...   Locator
   +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The L2 EID record follows the structure as described in [RFC6830].

5.2.3.  Interface to the LISP Mapping System

   The interface between the xTRs and the Mapping System is described in
   [RFC6833] and this document follows the specification as described
   there.  When available, the registrations MAY be implemented over a
   reliable transport as described in
   [I-D.kouvelas-lisp-map-server-reliable-transport].

   In order to support system convergence after mobility, when the Map-
   Server receives a new registration for a specific EID, it MUST send a
   Map-Notify to the entire RLOC set in the site that last registered
   this same EID.  This Map-Notify is used to track moved-away state of
   L2 EIDs as described in Section 5.2.4.

5.2.4.  SMR support to track L2 hosts that moved away

   In order to support mobility, an ETR SHALL maintain a list of EID
   records for which it has to generate a SMR message whenever it
   receives traffic with that EID as destination.






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   The particular strategy to maintain a SMR table is implementation
   specific.  In essence the table SHOULD provide support for the
   following:

   o  Keep track of end-hosts that were once connected to an ETR and
      have moved away.

   o  Support for L2 EID records, the 2-tuple (IID, MAC), for which a
      SMR message SHOULD be generated.

5.2.5.  L2 Broadcast and Multicast traffic

   Broadcast and Multicast traffic on the L2-overlay is supported by
   either replicated unicast, or underlay (RLOC) multicast.

   xTRs that offer L2 overlay services and are part of the same
   Instance-ID join a common Multicast Group.  When required, this group
   allows ITRs to send traffic that needs to be replicated (flooded) to
   all ETRs participating in the L2-overlay (e.g., broadcast traffic
   within a subnet).  When the core network (RLOC space) supports native
   multicast ETRs participating in the L2-overlay join a (*,G) group
   associated to the Instance-ID.

   When multicast is not available in the core network, each xTR that is
   part of the same instance-ID SHOULD register a (S,G) entry to the
   mapping system using the procedures described in
   [I-D.ietf-lisp-signal-free-multicast], where S is 0000-0000-0000/0
   and G is ffff-ffff-ffff/48.  This strategy allows and ITR to know
   which ETRs are part of the L2 overlay and it can head-end replicate
   traffic to.

   Following the same case, when multicast is not available in the core
   network, the procedures in [I-D.ietf-lisp-signal-free-multicast] can
   be used to ensure proper distribution of link-local multicast traffic
   across xTRs participating in the L2 overlay.  In such case, the xTRs
   SHOULD join a (S,G) entry with S being 0000-0000-0000/0 and where G
   is 0100-0000-0000/8.

5.2.6.  L2 Unknown Unicast Support

   An ITR attempts to resolve MAC destination misses through the Mapping
   System.  When the destination host remains undiscovered the
   destination is considered an Unknown Unicast.

   A Map-Server SHOULD respond to a Map-Request for an undiscovered host
   with a Negative Map-Reply with action "Native Forward".
   Alternatively the action "Drop" may be used in order to suppress
   Unknown Unicast forwarding.



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   An ITR that receives a Negative Map-Reply with Action "Native
   Forward" will handle traffic for the undiscovered host as L2
   Broadcast traffic and will be unicast replicated or flooded using
   underlay multicast to the rest of ETRs in the Layer-2 overlay.

   Upon discovery of a previously unknown unicast MAC EID, a data
   triggered SMR for the discovered EID should be sent by the discovery
   ETR back to the ITRs that are flooding the unknown unicast traffic.
   This would allow ITRs to refresh their caches and stop flooding
   unknown unicast traffic as necessary.

5.2.7.  Time-to-Live Handling in Data-Plane

   When using a L2 overlay and the encapsulated traffic is IP traffic,
   the Time-to-Live value of the inner IP header MUST remain unmodified
   during encapsulation and decapsulation.  Network hops traversed as
   part of the L2 overlay SHOULD be hidden to tools like traceroute and
   applications that require direct L2 connectivity.

5.3.  Support to ARP resolution through Mapping System

5.3.1.  Map-Server support to ARP resolution: Packet Flow

   A large majority of applications are IP based and, as a consequence,
   end systems are typically provisioned with IP addresses as well as
   MAC addresses.

   In this case, to limit the flooding of ARP traffic and reduce the use
   of multicast in the RLOC network, the LISP mapping system MAY be used
   to support ARP resolution at the ITR.

   In order to provide this support, ETRs handle and register an
   additional EID-to-RLOC mapping as follows,

   o  EID-record contents = <IID, IP>, RLOC-record contents <MAC>.

   There is a dedicated IID used for the registration of the ARP related
   mappings.  Thus, a system with L2 and L3 overlays as well as ARP
   mappings would have three IIDs at play.  In the spirit of providing
   clarity, we will refer to those IIDs as L2-IID, L3-IID and ARP-IID
   respectively.  By using these definitions, we do not intend to coin
   new terminology, nor is there anything special about those IIDs that
   would make them differ from the generic definition of an IID.  The
   types of mappings expected in such a system are summarized below:

   o  EID = <IID1, IP> to RLOC = <IP-RLOC> (L3-overlay)

   o  EID = <IID2, MAC> to RLOC = <IP-RLOC> (L2-overlay)



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   o  EID = <IID3, IP> to RLOC = <MAC-RLOC> (ARP/ND mapping)

   The following packet flow sequence describes the use of the LISP
   Mapping System to support ARP resolution for hosts residing in a
   subnet that is extended to multiple sites.  Using Figure 1, End-
   Device 2 tries to find the MAC address of End-Device 3.  Note that
   both have IP addresses within the same subnet:

   o  End-Device 2 sends a broadcast ARP message to discover the MAC
      address of End-Device 3.  The ARP request targets IP 3.0.0.3.

   o  ITR B receives the ARP message, but rather than flooding it on the
      overlay network sends a Map-Request to the mapping database system
      for EID = <IID2,3.0.0.3>.

   o  When receiving the Map-Request, the Map-Server sends a Proxy-Map-
      Reply back to ITR B with the mapping EID = <IID2,3.0.0.3> -> MAC
      0:0:3:0:0:3.

   o  Using this Map-Reply, ITR B sends an ARP-Reply back to End-Device
      2 with the tuple IP 3.0.0.3, MAC 0:0:3:0:0:3.

   o  End-Device 2 learns MAC 0:0:3:0:0:3 from the ARP message and can
      now send a L2 traffic to End-Device 3.  When this traffic reaches
      ITR B is sent over the L2-overlay as described above in
      Section 5.1.1.

   This example shows how LISP, by replacing dynamic data plane learning
   (such as Flood-and-Learn) can reduce the use of multicast in the
   underlay network.

   Note that ARP resolution using the Mapping System is a stateful
   operation on the ITR.  The source IP,MAC tuple coming from the ARP
   request have to be stored to generate the ARP-reply when the Map-
   Reply is received.

   Note that the ITR SHOULD cache the ARP entry.  In that case future
   ARP-requests can be handled without sending additional Map-Requests.

5.3.2.  ARP registrations: MAC as a locator record

   When an end-host is attached or detected in an ETR that provides
   L2-overlay services and also supports ARP resolution using the LISP
   control-plane, an additional mapping entry is registered to the
   mapping system:

   o  The EID 2-tuple (IID, IP) and its binding to a corresponding host
      MAC address.



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   In this case both the xTRs and the Mapping System MUST support an
   EID-to-RLOC mapping where the MAC address is set as a locator record.

   In order to guarantee compatibility with current implementations of
   xTRs, the MAC locator record SHALL be encoded following the AFI-List
   LCAF Type defined in [I-D.ietf-lisp-lcaf].  This option would also
   allow adding additional attributes to the locator record, while
   maintaining compatibility with legacy devices.

   This mapping is registered with the Mapping System using the
   following EID record structure,

   +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   |                          Record TTL                           |
   |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   E   | Locator Count | EID mask-len  | ACT |A|      Reserved         |
   I   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   D   | Rsvd  |  Map-Version Number   |         AFI = 16387           |
   |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   r   |    Rsvd1     |     Flags      |   Type = 2    | IID mask-len  |
   e   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   c   |             4 + n             |        Instance-ID...         |
   o   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   r   |       ...Instance-ID          |        EID-AFI = 1 or 2       |
   d   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   |                    EID-Prefix (IPv4 or IPv6)                  |
   |   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  /|    Priority   |    Weight     |  M Priority   |   M Weight    |
   | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | M |        Unused Flags     |L|p|R|        AFI = 16387            |
   | A +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | C |    Rsvd1     |     Flags      |   Type = 1    |     Rsvd2     |
   | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | | |             2 + 6             |             AFI = 6           |
   | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | | |                    Layer-2 MAC Address  ...                   |
   | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  \| ... Layer-2 MAC Address       |
   +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+.

   An EID record with a locator record that carries a MAC address
   follows the same structure as described in [RFC6830].  However, some
   fields of the EID record and the locator record require special
   consideration:

   Locator Count:  This value SHOULD be set to 1.





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   Instance-ID:  This is the IID used to provide segmentation of the
      L2-overlays, L3 overlays and ARP tables.

   Priority and Weight:  IP to MAC bindings are one to one bindings.  An
      ETR SHOULD not register more than one MAC address in the locator
      record together with an IP based EID.  The Priority of the MAC
      address record is set to 255.  The Weight value SHOULD be ignored
      and the recommendation is to set it to 0.

   L bit:  This bit of the locator record SHOULD only be set to 1 when
      an ETR is registering its own IP to MAC binding.

   p bit:  This bit of the locator record SHOULD be set to 0.

   R bit:  This bit of the locator record SHOULD be set to 0.

   Note that an IP EID record that carries a MAC address in the locator
   record, SHALL be registered with the Proxy Map-Reply bit set.

5.3.3.  Implementation Considerations

   While ARP support through the LISP Mapping System fits the LISP
   Control-Plane there are a series of considerations to take into
   account when providing this feature:

   o  As indicated, when and end-host is attached the ETR maintains and
      registers a mapping with the binding EID = <IID, IP> -> RLOC =
      <MAC>.

   o  ARP support through the LISP Mapping System is OPTIONAL and the
      xTRs should allow the possibility to enable or disable the
      feature.

   o  When the ARP entry has not been registered, a Map Server SHOULD
      send a Negative Map-Reply with action "No Action" as a response to
      an ARP based Map Request.

   o  In case the ITR receives a Negative Map-Reply for an ARP request
      it should fallback to flooding the ARP packet as any other L2
      Broadcast packet (as described in Section 5.2.5).

   o  When receiving a positive Map-Reply for an ARP based Map-Request,
      the ETR MUST recreate the actual ARP Reply, impersonating the real
      host.  As a consequence, ARP support is a stateful operation where
      the ITR needs to store enough information about the host that
      generates an ARP request in order to recreate the ARP Reply.





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   o  ARP replies learned from the Mapping System SHOULD be cached and
      the information used to reply to subsequent ARP requests to the
      same hosts.

6.  Optional Deployment Models

   The support of an integrated L2 and L3 overlay solution takes
   multiple architectural design options, that depend on the specific
   requirements of the deployment environment.  While some of the
   previous describe specific packet flows and solutions based on the
   recommended solution, this section documents OPTIONAL design
   considerations that differ from the recommended one but that MAY be
   required on alternative deployment environments.

6.1.  IP Forwarding of Intra-subnet Traffic

   As pointed out at the beginning the recommended selection of the L2
   and L3 overlays is not the only one possible.  In fact, providing L2
   extension to some cloud platforms is not always possible and subnets
   need to be extended using the L3 overlay.

   In order to send all IP traffic (intra- and inter-subnet) through the
   L3 overlay the solution MUST change the ARP resolution process
   described in Section 5.3.1 to the following one (we follow again
   Figure 1 to drive the example.  End-Device 2 queries about End-Device
   3):

   o  End-Device 1 sends a broadcast ARP message to discover the MAC
      address of 3.0.0.3.

   o  ITR B receives the ARP message and sends a Map-Request to the
      Mapping System for EID = <IID1,3.0.0.3>.

   o  In this case, the Map-Request is routed by the Mapping system
      infrastructure to ETR C, that will send a Map-Reply back to ITR B
      containing the mapping EID = <IID1,3.0.0.3> -> RLOC=IP_C.

   o  ITR B populates its local cache with the received entry on the L3
      forwarding table.  Then, using the cache information it sends a
      Proxy ARP-reply with its own MAC (MAC_xTR_B) address to end End-
      Device 1.

   o  End-Device 1 learns MAC_ITR_B from the proxy ARP-reply and sends
      traffic with destination address 3.0.0.3 and destination MAC,
      MAC_xTR_B.

   o  As the destination MAC address is the one from xTR B, when xTR B
      receives this traffic it is forwarded using the L3-overlay.



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   o  Note that when implementing this solution, when a host that is
      local to an ETR moves away, the ETR SHOULD locally send a
      Gratuitous ARP with its own MAC address and the IP of the moved
      host, to refresh the ARP tables of local hosts and guarantee the
      use of the L3 overlay when connecting to the remote host.

   It is also important to note that using this strategy to extend
   subnets through the L3 overlay but still keeping the L2 overlay for
   the rest of traffic MAY lead to flow asymmetries.  This MAY be the
   case in deployments that filter Gratuitous ARPs, or when moved hosts
   continue using actual L2 information collected before a migration.

6.2.  Data-plane Encapsulation Options

   The LISP control-plane offers independence from the data-plane
   encapsulation.  Any encapsulation format that can carry a 24-bit
   instance-ID can be used to provide the unified overlay.

   Common encapsulation formats that can be used are [VXLAN-GPE], [LISP]
   and [VXLAN]:

   o  VXLAN-GPE encap: This encapsulation format is defined in
      [I-D.ietf-nvo3-vxlan-gpe].  It allows encapsulation both L2 and L3
      packets and the VNI field directly maps to the Instance-ID used in
      the control plane.  Note that when using this encapsulation for a
      unified solution the P-bit is set and the Next-Protocol field is
      used (typically with values 0x1 (IPv4) or 0x2 (IPv6) in
      L3-overlays, and value 0x3 in L2-overlays).

   o  LISP encap: This is the encapsulation format defined in the
      original LISP specification [RFC6830].  The encapsulation allows
      encapsulating both L2 and L3 packets.  The Instance-ID used in the
      EIDs directly maps to the Instance-ID that the LISP header
      carries.  At the ETR, after decapsulation, the IID MAY be used to
      decide between L2 processing or L3 processing.

   o  VXLAN encap: This is a L2 encapsulation format defined in
      [RFC7348].  While being a L2 encapsulation it can be used both for
      L2 and L3 overlays.  The Instance-ID used in LISP signaling maps
      to the VNI field of the VXLAN header.  Providing L3 overlays using
      VXLAN generally requires using the ETR MAC address as destination
      MAC address of the inner Ethernet header.  The process to learn or
      derive this ETR MAC address is not included as part of this
      document.







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7.  IANA Considerations

   This memo includes no request to IANA.

8.  Acknowledgements

   This draft builds on top of two expired drafts that introduced the
   concept of LISP L2/L3 overlays (draft-maino-nvo3-lisp-cp and draft-
   hertoghs-nvo3-lisp-controlplane-unified).  Many thanks to the
   combined authors of those drafts, that SHOULD be considered main
   contributors of this draft as well: Vina Ermagan, Dino Farinacci,
   Yves Hertoghs, Luigi Iannone, Fabio Maino, Victor Moreno, and Michael
   Smith.

9.  References

9.1.  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>.

   [RFC6830]  Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The
              Locator/ID Separation Protocol (LISP)", RFC 6830,
              DOI 10.17487/RFC6830, January 2013,
              <http://www.rfc-editor.org/info/rfc6830>.

   [RFC6831]  Farinacci, D., Meyer, D., Zwiebel, J., and S. Venaas, "The
              Locator/ID Separation Protocol (LISP) for Multicast
              Environments", RFC 6831, DOI 10.17487/RFC6831, January
              2013, <http://www.rfc-editor.org/info/rfc6831>.

   [RFC6833]  Fuller, V. and D. Farinacci, "Locator/ID Separation
              Protocol (LISP) Map-Server Interface", RFC 6833,
              DOI 10.17487/RFC6833, January 2013,
              <http://www.rfc-editor.org/info/rfc6833>.

   [RFC7348]  Mahalingam, M., Dutt, D., Duda, K., Agarwal, P., Kreeger,
              L., Sridhar, T., Bursell, M., and C. Wright, "Virtual
              eXtensible Local Area Network (VXLAN): A Framework for
              Overlaying Virtualized Layer 2 Networks over Layer 3
              Networks", RFC 7348, DOI 10.17487/RFC7348, August 2014,
              <http://www.rfc-editor.org/info/rfc7348>.







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9.2.  Informative References

   [I-D.coras-lisp-re]
              Coras, F., Cabellos-Aparicio, A., Domingo-Pascual, J.,
              Maino, F., and D. Farinacci, "LISP Replication
              Engineering", draft-coras-lisp-re-08 (work in progress),
              November 2015.

   [I-D.ietf-lisp-ddt]
              Fuller, V., Lewis, D., Ermagan, V., Jain, A., and A.
              Smirnov, "LISP Delegated Database Tree", draft-ietf-lisp-
              ddt-08 (work in progress), September 2016.

   [I-D.ietf-lisp-lcaf]
              Farinacci, D., Meyer, D., and J. Snijders, "LISP Canonical
              Address Format (LCAF)", draft-ietf-lisp-lcaf-16 (work in
              progress), October 2016.

   [I-D.ietf-lisp-signal-free-multicast]
              Moreno, V. and D. Farinacci, "Signal-Free LISP Multicast",
              draft-ietf-lisp-signal-free-multicast-01 (work in
              progress), April 2016.

   [I-D.ietf-nvo3-vxlan-gpe]
              Kreeger, L. and U. Elzur, "Generic Protocol Extension for
              VXLAN", draft-ietf-nvo3-vxlan-gpe-02 (work in progress),
              April 2016.

   [I-D.kouvelas-lisp-map-server-reliable-transport]
              Cassar, C., Kouvelas, I., Lewis, D., Arango, J., and J.
              Leong, "LISP Map Server Reliable Transport", draft-
              kouvelas-lisp-map-server-reliable-transport-02 (work in
              progress), August 2016.

Authors' Addresses

   Marc Portoles Comeras
   Cisco Systems
   170 Tasman Drive
   San Jose, CA  95134
   USA

   Email: mportole@cisco.com








Portoles, et al.         Expires April 11, 2017                [Page 22]


Internet-Draft             L2/L3 EID Mobility               October 2016


   Vrushali Ashtaputre
   Cisco Systems
   170 Tasman Drive
   San Jose, CA  95134
   USA

   Email: vrushali@cisco.com


   Victor Moreno
   Cisco Systems
   170 Tasman Drive
   San Jose, CA  95134
   USA

   Email: vimoreno@cisco.com


   Fabio Maino
   Cisco Systems
   170 Tasman Drive
   San Jose, CA  95134
   USA

   Email: fmaino@cisco.com


   Dino Farinacci
   lispers.net
   San Jose, CA
   USA

   Email: farinacci@gmail.com


















Portoles, et al.         Expires April 11, 2017                [Page 23]


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