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Versions: (draft-xiao-bfd-geneve) 00

NVO3 Working Group                                                X. Min
Internet-Draft                                                 G. Mirsky
Intended status: Informational                                       ZTE
Expires: January 9, 2020                                    July 8, 2019


                             BFD for Geneve
                     draft-xiao-nvo3-bfd-geneve-00

Abstract

   This document describes the use of the Bidirectional Forwarding
   Detection (BFD) protocol in point-to-point Generic Network
   Virtualization Encapsulation (Geneve) tunnels forming up an overlay
   network.

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
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   Internet-Drafts are draft documents valid for a maximum of six months
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   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 January 9, 2020.

Copyright Notice

   Copyright (c) 2019 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
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
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   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.




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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions Used in This Document . . . . . . . . . . . . . .   2
     2.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   2
     2.2.  Requirements Language . . . . . . . . . . . . . . . . . .   3
   3.  BFD Packet Transmission over Geneve Tunnel  . . . . . . . . .   3
     3.1.  BFD Encapsulation With Inner Ethernet/IP/UDP Header . . .   3
     3.2.  BFD Encapsulation With Inner IP/UDP Header  . . . . . . .   5
     3.3.  BFD Encapsulation With Inner MPLS Header  . . . . . . . .   7
     3.4.  BFD Encapsulation With Inner OAM Shim . . . . . . . . . .   9
   4.  Reception of BFD packet from Geneve Tunnel  . . . . . . . . .  10
     4.1.  Demultiplexing of the BFD packet  . . . . . . . . . . . .  11
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  12
   8.  Normative References  . . . . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   "Generic Network Virtualization Encapsulation" (Geneve)
   [I-D.ietf-nvo3-geneve] provides an encapsulation scheme that allows
   building an overlay network by decoupling the address space of the
   attached virtual hosts from that of the network.

   This document describes the use of Bidirectional Forwarding Detection
   (BFD) protocol [RFC5880] to enable monitoring continuity of the path
   between two Geneve tunnel endpoints, which may be NVE (Network
   Virtualization Edge) or other device acting as a Geneve tunnel
   endpoint.  For simplicity, in this document, NVE is used to represent
   Geneve tunnel endpoint, Virtual Machine (VM) is used to represent the
   device attached to a Geneve tunnel endpoint from the outside.

   The use cases and the deployment of BFD for Geneve are consistent
   with what's described in Section 1 and Section 3 of
   [I-D.ietf-bfd-vxlan].  The major difference between Geneve and
   "Virtual eXtensible Local Area Network" (VXLAN) [RFC7348]
   encapsulation is that Geneve supports multi-protocol payload and
   variable length options.

2.  Conventions Used in This Document

2.1.  Terminology

   BFD: Bidirectional Forwarding Detection

   CC: Continuity Check



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   GAL: Generic Associated Channel Label

   G-ACh: Generic Associated Channel

   Geneve: Generic Network Virtualization Encapsulation

   MPLS: Multiprotocol Label Switching

   NVE: Network Virtualization Edge

   VM: Virtual Machine

   VNI: Virtual Network Identifier

   VXLAN: Virtual eXtensible Local Area Network

2.2.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

3.  BFD Packet Transmission over Geneve Tunnel

   Concerning whether or not the Geneve data packets include an IP
   protocol data unit, and whether or not the Geneve data packets
   include an MPLS protocol data unit, this document considers four
   options of BFD packet encapsulation in Geneve.

3.1.  BFD Encapsulation With Inner Ethernet/IP/UDP Header

   If the Protocol Type field (as defined in Section 3.4 of
   [I-D.ietf-nvo3-geneve]) of data packets indicates that there exists
   an inner Ethernet header, i.e., the Protocol Type equals to 0x6558
   (Ethernet frame), then BFD packets are encapsulated in Geneve as
   described below.  The Geneve packet format over IPv4 is defined in
   Section 3.1 of [I-D.ietf-nvo3-geneve].  The Geneve packet format over
   IPv6 is defined in Section 3.2 of [I-D.ietf-nvo3-geneve].  The Outer
   IP/UDP and Geneve headers MUST be encoded by the sender as defined in
   [I-D.ietf-nvo3-geneve].  Note that the outer IP header and the inner
   IP header may not be of the same address family, in other words,
   outer IPv6 header accompanied with inner IPv4 header and outer IPv4
   header accompanied with inner IPv6 header are both possible.






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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                      Outer Ethernet Header                    ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Outer IPvX Header                      ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Outer UDP Header                       ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                          Geneve Header                        ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                      Inner Ethernet Header                    ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Inner IPvX Header                      ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                         Inner UDP Header                      ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                       BFD Control Message                     ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               FCS                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   Figure 1: Geneve Encapsulation of BFD Control Message With the Inner
                          Ethernet/IP/UDP Header

   The BFD packet MUST be carried inside the inner Ethernet frame of the
   Geneve packet, as specified in Section 4 of [I-D.ietf-bfd-vxlan].

   When the BFD packets are encapsulated in Geneve in this way, the
   Geneve header follows the value set below.




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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |Ver|  Opt Len  |O|C|    Rsvd.  |          Protocol Type        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |        Virtual Network Identifier (VNI)       |    Reserved   |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                    Variable Length Options                    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                          Figure 2: Geneve Header

   Opt Len field SHOULD be set to 0, which indicates there isn't any
   variable length option.

   [Ed.Note]: Use of O bit is still being discussed in the NVO3 WG, so
   the value is undetermined.

   C bit MUST be set to 0.

   Protocol Type field MUST be set to 0x6558 (Ethernet frame).

3.2.  BFD Encapsulation With Inner IP/UDP Header

   If the Protocol Type field (as defined in Section 3.4 of
   [I-D.ietf-nvo3-geneve]) of data packets indicates that there exists
   an inner IP header, i.e., the Protocol Type equals to 0x0800 (IPv4)
   or 0x86DD (IPv6), then BFD packets are encapsulated in Geneve as
   described below.  The Geneve packet format over IPv4 is defined in
   Section 3.1 of [I-D.ietf-nvo3-geneve].  The Geneve packet format over
   IPv6 is defined in Section 3.2 of [I-D.ietf-nvo3-geneve].  The Outer
   IP/UDP and Geneve headers MUST be encoded by the sender as defined in
   [I-D.ietf-nvo3-geneve].  Note that the outer IP header and the inner
   IP header may not be of the same address family, in other words,
   outer IPv6 header accompanied with inner IPv4 header and outer IPv4
   header accompanied with inner IPv6 header are both possible.














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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                      Outer Ethernet Header                    ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Outer IPvX Header                      ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Outer UDP Header                       ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                          Geneve Header                        ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Inner IPvX Header                      ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                         Inner UDP Header                      ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                       BFD Control Message                     ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               FCS                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   Figure 3: Geneve Encapsulation of BFD Control Message With the Inner
                               IP/UDP Header

   The BFD packet MUST be carried inside the inner IP packet of the
   Geneve packet.  The inner IP packet carrying the BFD payload has the
   following format:

      IP header:

         Source IP: IP address of the VM-facing interface of the
         originating NVE.





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         Destination IP: IP address of the VM-facing interface of the
         terminating NVE.

         TTL: MUST be set to 1 to ensure that the BFD packet is not
         routed within the L3 underlay network.

      The fields of the UDP header and the BFD control packet are
      encoded as specified in [RFC5881].

   When the BFD packets are encapsulated in Geneve in this way, the
   Geneve header follows the value set below.

   Opt Len field SHOULD be set to 0, which indicates there isn't any
   variable length option.

   [Ed.Note]: Use of O bit is still being discussed in the NVO3 WG, so
   the value is undetermined.

   C bit MUST be set to 0.

   Protocol Type field MUST be set to 0x0800 (IPv4) or 0x86DD (IPv6),
   depending on the address family of the inner IP packet.

3.3.  BFD Encapsulation With Inner MPLS Header

   If the Protocol Type field (as defined in Section 3.4 of
   [I-D.ietf-nvo3-geneve]) of data packets indicates that there exists
   an inner MPLS header, i.e., the Protocol Type equals to 0x8847 (MPLS)
   or 0x8848 (MPLS with the upstream-assigned label), then BFD packets
   are encapsulated in Geneve as described below.  The Geneve packet
   format over IPv4 is defined in Section 3.1 of [I-D.ietf-nvo3-geneve].
   The Geneve packet format over IPv6 is defined in Section 3.2 of
   [I-D.ietf-nvo3-geneve].  The Outer IP/UDP and Geneve headers MUST be
   encoded by the sender as defined in [I-D.ietf-nvo3-geneve].

















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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                      Outer Ethernet Header                    ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Outer IPvX Header                      ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Outer UDP Header                       ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                          Geneve Header                        ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                 MPLS Interface Context Label                  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                            MPLS GAL                           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                           MPLS G-ACh                          |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                       BFD Control Message                     ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               FCS                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   Figure 4: Geneve Encapsulation of BFD Control Message With the Inner
                              MPLS GAL/G-ACh

   The BFD packet MUST be carried inside the inner MPLS packet of the
   Geneve packet.  The inner MPLS packet carrying the BFD payload has
   the following format:

      MPLS Interface Context Label: This Label would be used to identify
      the VM-facing interface of the originating NVE and the VM-facing
      interface of the terminating NVE.

      MPLS GAL(Generic Associated Channel Label):

         Label value: MUST be set to 13, as specified in [RFC5586].




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         S bit: MUST be set to 1.

         TTL: MUST be set to 1.

      The fields of the MPLS G-ACh(Generic Associated Channel) and the
      BFD control packet are encoded as specified for MPLS-TP
      CC(Continuity Check) message in [RFC6428].

   When the BFD packets are encapsulated in Geneve in this way, the
   Geneve header follows the value set below.

   Opt Len field SHOULD be set to 0, which indicates there isn't any
   variable length option.

   [Ed.Note]: Use of O bit is still being discussed in the NVO3 WG, so
   the value is undetermined.

   C bit MUST be set to 0.

   Protocol Type field MUST be set to 0x8847 (MPLS).

3.4.  BFD Encapsulation With Inner OAM Shim

   Also, if the BFD control packet is encapsulated in Geneve without the
   use of IP/UDP header or MPLS G-ACh header, the BFD control packet MAY
   be identified through the Geneve OAM shim.  The layout of the
   Ethernet frame is shown in Figure 5.  Protocol Type field MUST be set
   to the value which indicates a Geneve OAM shim that will have a field
   to indicate the inner BFD control packet.  The value of the Protocol
   Type field and the format of the Geneve OAM shim are defined in
   [I-D.mmbb-nvo3-geneve-oam].  The Geneve OAM shim immediately follows
   the Geneve header, and the BFD control packet immediately follows the
   Geneve OAM shim.


















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    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                      Outer Ethernet Header                    ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Outer IPvX Header                      ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                        Outer UDP Header                       ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                         Geneve Header                         ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                        Geneve OAM Shim                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                                                               |
   ~                       BFD Control Message                     ~
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                               FCS                             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


   Figure 5: Geneve Encapsulation of BFD Control Message With Geneve OAM
                                   Shim

4.  Reception of BFD packet from Geneve Tunnel

   Once a packet is received, NVE MUST validate the packet as described
   in [I-D.ietf-nvo3-geneve].

   If the Protocol Type field equals 0x0800 (IPv4) or 0x86DD (IPv6), and
   the Destination IP of the inner IP packet matches the VM-facing
   interface IP address of the NVE, the UDP destination port and the TTL
   of the inner IP packet MUST be validated to determine whether the
   received packet can be processed by BFD.  BFD packet with inner IP
   set to NVE MUST NOT be forwarded to VMs.

   If the Protocol Type field equals 0x8847 (MPLS), the MPLS Interface
   Context Label, the MPLS GAL and the MPLS G-ACh of the inner MPLS
   packet MUST be validated to determine whether the received packet can




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   be processed by BFD.  BFD packet with MPLS GAL MUST NOT be forwarded
   to VMs.

   If the Protocol Type field equals 0x8902 which indicates a Geneve OAM
   shim that will have a field to indicate the inner BFD control
   message, as specified in [I-D.mmbb-nvo3-geneve-oam], the received
   packet MUST be processed by BFD and MUST NOT be forwarded to VMs.

4.1.  Demultiplexing of the BFD packet

   Since multiple BFD sessions may be running between two NVEs, and
   multiple BFD sessions may be originating or terminating at one NVE,
   there needs to be a mechanism for demultiplexing received BFD packets
   to the proper session.

   If the BFD packet is received with Your Discriminator equals to 0,
   for different BFD encapsulation, the procedure for demultiplexing the
   received BFD packets is different.

      When the BFD Encapsulation With Inner Ethernet/IP/UDP Header is
      used, the BFD session MUST be identified using the procedure
      specified in Section 5.1 of [I-D.ietf-bfd-vxlan].

      When the BFD Encapsulation With Inner IP/UDP Header is used, the
      BFD session MUST be identified using the inner IP/UDP header,
      i.e., the source IP and the destination IP present in the inner
      IP/UDP header.

      When the BFD Encapsulation With Inner MPLS Header is used, the BFD
      session MUST be identified using the inner MPLS header, i.e., the
      MPLS Interface Context Label present in the inner MPLS header.

      When the BFD Encapsulation With Inner OAM Shim is used, the
      procedure for demultiplexing the received BFD packets to the
      proper session is for further study.

   If the BFD packet is received with non-zero Your Discriminator, then
   BFD session MUST be demultiplexed only with Your Discriminator as the
   key.

   With respect to BFD for Geneve, the use of the specific VNI would
   follow the principle as specified in Section 6 of
   [I-D.ietf-bfd-vxlan].








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5.  Security Considerations

   This document does not raise any additional security issues beyond
   those of the specifications referred to in the list of normative
   references.

6.  IANA Considerations

   This document has no IANA action requested.

7.  Acknowledgements

   The authors would like to acknowledge Reshad Rahman, Jeffrey Haas and
   Matthew Bocci for their guidance on this work.

8.  Normative References

   [I-D.ietf-bfd-vxlan]
              Networks, J., Paragiri, S., Govindan, V., Mudigonda, M.,
              and G. Mirsky, "BFD for VXLAN", draft-ietf-bfd-vxlan-07
              (work in progress), May 2019.

   [I-D.ietf-nvo3-geneve]
              Gross, J., Ganga, I., and T. Sridhar, "Geneve: Generic
              Network Virtualization Encapsulation", draft-ietf-
              nvo3-geneve-13 (work in progress), March 2019.

   [I-D.mmbb-nvo3-geneve-oam]
              Mirsky, G., Xiao, M., Boutros, S., and D. Black, "OAM for
              use in GENEVE", draft-mmbb-nvo3-geneve-oam-00 (work in
              progress), July 2019.

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

   [RFC5586]  Bocci, M., Ed., Vigoureux, M., Ed., and S. Bryant, Ed.,
              "MPLS Generic Associated Channel", RFC 5586,
              DOI 10.17487/RFC5586, June 2009,
              <https://www.rfc-editor.org/info/rfc5586>.

   [RFC5880]  Katz, D. and D. Ward, "Bidirectional Forwarding Detection
              (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
              <https://www.rfc-editor.org/info/rfc5880>.






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   [RFC5881]  Katz, D. and D. Ward, "Bidirectional Forwarding Detection
              (BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881,
              DOI 10.17487/RFC5881, June 2010,
              <https://www.rfc-editor.org/info/rfc5881>.

   [RFC6428]  Allan, D., Ed., Swallow, G., Ed., and J. Drake, Ed.,
              "Proactive Connectivity Verification, Continuity Check,
              and Remote Defect Indication for the MPLS Transport
              Profile", RFC 6428, DOI 10.17487/RFC6428, November 2011,
              <https://www.rfc-editor.org/info/rfc6428>.

   [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,
              <https://www.rfc-editor.org/info/rfc7348>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

Authors' Addresses

   Xiao Min
   ZTE
   Nanjing
   China

   Phone: +86 25 88016574
   Email: xiao.min2@zte.com.cn


   Greg Mirsky
   ZTE
   USA

   Email: gregimirsky@gmail.com













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