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Network Working Group                                       F. Brockners
Internet-Draft                                               S. Bhandari
Intended status: Informational                              C. Pignataro
Expires: May 3, 2017                                               Cisco
                                                              H. Gredler
                                                            RtBrick Inc.
                                                                J. Leddy
                                                                 Comcast
                                                               S. Youell
                                                                    JMPC
                                                              T. Mizrahi
                                                                 Marvell
                                                                D. Mozes
                                              Mellanox Technologies Ltd.
                                                             P. Lapukhov
                                                                Facebook
                                                                R. Chang
                                                       Barefoot Networks
                                                        October 30, 2016


                  Encapsulations for In-situ OAM Data
                draft-brockners-inband-oam-transport-02

Abstract

   In-situ Operations, Administration, and Maintenance (OAM) records
   operational and telemetry information in the packet while the packet
   traverses a path between two points in the network.  In-situ OAM is
   to complement current out-of-band OAM mechanisms based on ICMP or
   other types of probe packets.  This document outlines how in-situ OAM
   data records can be transported in protocols such as NSH, Segment
   Routing, VXLAN-GPE, native IPv6 (via extension headers), and IPv4.
   Transport options are currently investigated as part of an
   implementation study.  This document is intended to only serve
   informational purposes.

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/.





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   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 May 3, 2017.

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
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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.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Conventions . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  In-Situ OAM Metadata Transport in IPv6  . . . . . . . . . . .   4
     3.1.  In-situ OAM in IPv6 Hop by Hop Extension Header . . . . .   5
       3.1.1.  In-situ OAM Hop by Hop Options  . . . . . . . . . . .   5
       3.1.2.  Procedure at the Ingress Edge to Insert the In-situ
               OAM Header  . . . . . . . . . . . . . . . . . . . . .   7
       3.1.3.  Procedure at Transit Nodes  . . . . . . . . . . . . .   8
       3.1.4.  Procedure at the Egress Edge to Remove the In-situ
               OAM Header  . . . . . . . . . . . . . . . . . . . . .   8
   4.  In-situ OAM Metadata Transport in IPv4  . . . . . . . . . . .   9
   5.  In-situ OAM Metadata Transport in VXLAN-GPE . . . . . . . . .   9
   6.  In-situ OAM Metadata Transport in NSH . . . . . . . . . . . .  11
   7.  In-situ OAM Metadata Transport in Segment Routing . . . . . .  13
     7.1.  In-situ OAM in SR with IPv6 Transport . . . . . . . . . .  13
     7.2.  In-situ OAM in SR with MPLS Transport . . . . . . . . . .  14
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
   9.  Manageability Considerations  . . . . . . . . . . . . . . . .  14
   10. Security Considerations . . . . . . . . . . . . . . . . . . .  14
   11. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  14
   12. References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     12.1.  Normative References . . . . . . . . . . . . . . . . . .  14
     12.2.  Informative References . . . . . . . . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16



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1.  Introduction

   This document discusses transport mechanisms for "in-situ"
   Operations, Administration, and Maintenance (OAM) data records.  In-
   situ OAM records OAM information within the packet while the packet
   traverses a particular network domain.  The term "in-situ" refers to
   the fact that the OAM data is added to the data packets rather than
   is being sent within packets specifically dedicated to OAM.  A
   discussion of the motivation and requirements for in-situ OAM can be
   found in [I-D.brockners-inband-oam-requirements].  Data types and
   data formats for in-situ OAM are defined in
   [I-D.brockners-inband-oam-data].

   This document outlines transport encapsulations for the in-situ OAM
   data defined in [I-D.brockners-inband-oam-data].  This document is to
   serve informational purposes only.  As part of an in-situ OAM
   implementation study different protocol encapsulations for in-situ
   OAM data are being explored.  Once data formats and encapsulation
   approaches are settled, protocol specific specifications for in-situ
   OAM data transport will address the standardization aspect.

   The data for in-situ OAM defined in [I-D.brockners-inband-oam-data]
   can be carried in a variety of protocols based on the deployment
   needs.  This document discusses transport of in-situ OAM data for the
   following protocols:

   o  IPv6

   o  IPv4

   o  VXLAN-GPE

   o  NSH

   o  Segment Routing (IPv6 and MPLS)

   This list is non-exhaustive, as it is possible to carry the in-situ
   OAM data in several other protocols and transports.

   A feasibility study of in-situ OAM is currently underway as part of
   the FD.io project [FD.io].  The in-situ OAM implementation study
   should be considered as a "tool box" to showcase how "in-situ" OAM
   can complement probe-packet based OAM mechanisms for different
   deployments and packet transport formats.  For details, see the open
   source code in the FD.io [FD.io].






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2.  Conventions

   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].

   Abbreviations used in this document:

   MTU:       Maximum Transmit Unit

   NSH:       Network Service Header

   OAM:       Operations, Administration, and Maintenance

   POT:       Proof of Transit

   SFC:       Service Function Chain

   SID:       Segment Identifier

   SR:        Segment Routing

   VXLAN-GPE: Virtual eXtensible Local Area Network, Generic Protocol
              Extension

3.  In-Situ OAM Metadata Transport in IPv6

   This mechanisms of in-situ OAM in IPv6 complement others proposed to
   enhance diagnostics of IPv6 networks, such as the IPv6 Performance
   and Diagnostic Metrics Destination Option described in
   [I-D.ietf-ippm-6man-pdm-option].  The IP Performance and Diagnostic
   Metrics Destination Option is destination focused and specific to
   IPv6, whereas in-situ OAM is performed between end-points of the
   network or a network domain where it is enabled and used.

   A historical note: The idea of IPv6 route recording was originally
   introduced by [I-D.kitamura-ipv6-record-route] back in year 2000.
   With IPv6 now being generally deployed and new concepts such as
   Segment Routing [I-D.ietf-spring-segment-routing] being introduced,
   it is imperative to further mature the Operations, Administration,
   and Maintenance mechanisms available to IPv6 networks.

   The in-situ OAM options translate into options for an IPv6 extension
   header.  The extension header would be inserted by either a host
   source of the packet, or by a transit/domain-edge node.  If the
   addition of the in-situ OAM Hop-by-Hop Option header would lead to
   the packet exceeding the MTU of the domain an error should be
   reported.  The methods and procedures of how the error is reported



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   are outside the scope of this document.  Likewise if an ICMPv6
   forwarding error occurs between encapsulating and decapsulating
   nodes, the node generating the ICMPv6 error should strip the in-situ
   OAM Hop-by-Hop Option header before sending the ICMPv6 message to the
   source.

3.1.  In-situ OAM in IPv6 Hop by Hop Extension Header

   This section defines in-situ OAM for IPv6 transport.  In-situ OAM
   data is transported as an IPv6 hop-by-hop extension header.

3.1.1.  In-situ OAM Hop by Hop Options

   Brief recap of the IPv6 hop-by-hop header as well as the options used
   for carrying in-situ OAM data:




































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    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |  Next Header  |  Hdr Ext Len  |                               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                               +
    |                                                               |
    .                                                               .
    .                            Options                            .
    .                                                               .
    |                                                               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- - - - - - - - -
      |  Option Type  |  Opt Data Len |  Option Data
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- - - - - - - - -

   With 2 highest order bits of Option Type indicating the following:

      00 - skip over this option and continue processing the header.

      01 - discard the packet.

      10 - discard the packet and, regardless of whether or not the
           packet's Destination Address was a multicast address, send an
           ICMP Parameter Problem, Code 2, message to the packet's
           Source Address, pointing to the unrecognized Option Type.

      11 - discard the packet and, only if the packet's Destination
           Address was not a multicast address, send an ICMP Parameter
           Problem, Code 2, message to the packet's Source Address,
           pointing to the unrecognized Option Type.

   3rd highest bit:

      0 - Option Data does not change en-route

      1 - Option Data may change en-route

   In-situ OAM data records are inserted as options in an IPv6 hop-by-
   hop extension header:

   1.  Tracing Option: The in-situ OAM Tracing option defined in
       [I-D.brockners-inband-oam-data] is represented as a IPv6 option
       in hop by hop extension header by allocating following type:

       Option Type:  001xxxxxx 8-bit identifier of the type of option.
          xxxxxx=TBD_IANA_TRACE_OPTION_IPV6.






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   2.  Proof of Transit Option: The in-situ OAM POT option defined in
       [I-D.brockners-inband-oam-data] is represented as a IPv6 option
       in hop by hop extension header by allocating following type:

       Option Type:  001xxxxxx 8-bit identifier of the type of option.
          xxxxxx=TBD_IANA_POT_OPTION_IPV6.

   3.  Edge to Edge Option: The in-situ OAM E2E option defined in
       [I-D.brockners-inband-oam-data] is represented as a IPv6 option
       in hop by hop extension header by allocating following type:

       Option Type:  000xxxxxx 8-bit identifier of the type of option.
          xxxxxx=TBD_IANA_E2E_OPTION_IPV6.

3.1.2.  Procedure at the Ingress Edge to Insert the In-situ OAM Header

   In an administrative domain where in-situ OAM is used, insertion of
   the in-situ OAM header is enabled at the required edge nodes (i.e. at
   the encapsulating/decapsulating nodes) by means of configuration.

   Such a configuration SHOULD allow selective enablement of in-situ OAM
   header insertion for a subset of traffic (e.g., one or several
   "pipes").

   Further the ingress edge node should be aware of maximum size of the
   header that can be inserted.  Details on how the maximum size/size of
   the in-situ OAM domain are retrieved are outside the scope of this
   document.























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   Let n = max number of nodes updating in-situ OAM data;
   (calculated based on the packet size and the minimal MTU on all
   links within the OAM domain)

   Let k = number of node data records that can be allocated
   by this node.

   Let node_data_size = size of each node_data based on
   in-situ OAM type.

   if (packet matches traffic for which in-situ OAM is enabled) {
       Create in-situ OAM hbyh ext-header with k node data records
       preallocated.
       Increment payload length in IPv6 header:
                         with size of in-situ OAM hbyh ext-header
       Populate node data at:
          (size of in-situ OAM hbyh ext-header = 8) + k * node_data_size
       from the beginning of the header
       Set Elements-left to: k - 1

       Update "Next Header" field in main IPv6 header and
       set "Next Header" field of OAM hbyh extension header
       appropriately.
    }

3.1.3.  Procedure at Transit Nodes

   If a network node receives a packet with an in-situ OAM header and it
   is enabled to process in-situ OAM data it performs the following:

   k = number of node data that this node can allocate

   if (in-situ OAM ext hbyh ext-header is present) {
       if (Elements-left > 0)) {
         populate node data at :
            node_data_start[Elements-left]
         Elements-left = Elements-left - 1
       }
   }

3.1.4.  Procedure at the Egress Edge to Remove the In-situ OAM Header










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   egress_edge = list of interfaces where in-situ OAM hbyh ext
                  header is to be stripped

   Before forwarding packet out of interfaces in egress_edge list:

   if (in-situ OAM hbyh ext-header is present) {
      remove the in-situ OAM hbyh ext-header,
      possibly store the record along with additional
      fields for analysis and export
      Decrement Payload Length in IPv6 header
      by size of in-situ OAM ext header

      Update "Next Header" field in main IPv6 header and
      set "Next Header" field of OAM hbyh extension header
      appropriately.
   }

4.  In-situ OAM Metadata Transport in IPv4

   Transport of in-situ OAM data in IPv4 will be detailed in a future
   version of this document.

5.  In-situ OAM Metadata Transport in VXLAN-GPE

   VXLAN-GPE [I-D.ietf-nvo3-vxlan-gpe] encapsulation is somewhat similar
   to IPv6 extension headers in that a series of headers can be
   contained in the header as a linked list.  The different in-situ OAM
   types are added as options within a new in-situ OAM protocol header
   in VXLAN GPE.  In an administrative domain where in-situ OAM is used,
   insertion of the in-situ OAM protocol header in VXLAN GPE is enabled
   at the VXLAN GPE tunnel endpoint which also serve as in-situ OAM
   encapsulating/decapsulating nodes by means of configuration.



















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   In-situ OAM header in VXLAN GPE header:

    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 IP Header                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                       Outer UDP Header                        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
   |R|R|Ver|I|P|R|O|          Reserved             | NP = i.s.OAM  |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ GPE
   |     Virtual Network Identifier (VNI)          | Reserved      |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
   | Type =i.s.OAM | i.s.OAM HDR len |  Reserved     | NP = IP/Eth |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+iOAM
   |                     in-situ OAM options                       |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +
   |                                                               |
   |                                                               |
   |                     Payload + Padding (L2/L3/ESP/...)         |
   |                                                               |
   |                                                               |
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The VXLAN-GPE header and fields are defined in
   [I-D.ietf-nvo3-vxlan-gpe]. in-situ OAM specific fields and header are
   defined here:

   Type:  8-bit unsigned integer defining in-situ OAM header type

   in-situ OAM HDR len:  8-bit unsigned integer.  Length of the in-situ
      OAM HDR in 8-octet units

   in-situ OAM options:  Variable-length field, of length such that the
      complete in-situ OAM header is an integer multiple of 8 octets
      long.  Contains one or more TLV-encoded options of the format:












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   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- - - - - - - - -
   |  Option Type  |  Opt Data Len |  Option Data
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- - - - - - - - -

      Option Type          8-bit identifier of the type of option.

      Opt Data Len         8-bit unsigned integer.  Length of the Option
                           Data field of this option, in octets.

      Option Data          Variable-length field.  Option-Type-specific
                           data.

   The in-situ OAM options defined in [I-D.brockners-inband-oam-data]
   are encoded with an option type allocated in the new in-situ OAM IANA
   registry - in-situ OAM_PROTOCOL_OPTION_REGISTRY_IANA_TBD.  In
   addition the following padding options are defined to be used when
   necessary to align subsequent options and to pad out the containing
   header to a multiple of 8 octets in length.

   Pad1 option  (alignment requirement: none)

       +-+-+-+-+-+-+-+-+
       |       0       |
       +-+-+-+-+-+-+-+-+
       NOTE: The format of the Pad1 option is a special case -- it does
             not have length and value fields.

       The Pad1 option is used to insert one octet of padding into the
       Options area of a header.  If more than one octet of padding is
       required, the PadN option, described next, should be used, rather
       than multiple Pad1 options.

   PadN option  (alignment requirement: none)

       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- - - - - - - - -
       |       1       |  Opt Data Len |  Option Data
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+- - - - - - - - -
       The PadN option is used to insert two or more octets of padding
       into the Options area of a header.  For N octets of padding, the
       Opt Data Len field contains the value N-2, and the Option Data
       consists of N-2 zero-valued octets.

6.  In-situ OAM Metadata Transport in NSH

   In Service Function Chaining (SFC) [RFC7665], the Network Service
   Header (NSH) [I-D.ietf-sfc-nsh] already includes path tracing
   capabilities [I-D.penno-sfc-trace], but currently does not offer a
   solution to securely prove that packets really traversed the service



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   chain.  The "Proof of Transit" capabilities (see
   [I-D.brockners-inband-oam-requirements] and
   [I-D.brockners-proof-of-transit]) of in-situ OAM can be leveraged
   within NSH.  In an administrative domain where in-situ OAM is used,
   insertion of the in-situ OAM data into the NSH header is enabled at
   the required nodes (i.e. at the in-situ OAM encapsulating/
   decapsulating nodes) by means of configuration.

   Proof of transit in-situ OAM data is added as NSH Type 2 metadata:

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |      TLV Class=Cisco (0x0009) |C|    Type=POT |R|    Len=4    |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
   |                           Random                              |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  P
   |                        Random(contd.)                         |  O
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  T
   |                         Cumulative                            |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
   |                    Cumulative (contd.)                        |  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+

   TLV Class:  Describes the scope of the "Type" field.  In some cases,
      the TLV Class will identify a specific vendor, in others, the TLV
      Class will identify specific standards body allocated types.  POT
      is currently defined using the Cisco (0x0009) TLV class.

   Type:  The specific type of information being carried, within the
      scope of a given TLV Class.  Value allocation is the
      responsibility of the TLV Class owner.  Currently a type value of
      0x94 is used for proof of transit

   Reserved bits:  Two reserved bit are present for future use.  The
      reserved bits MUST be set to 0x0.

   F: One bit.  Indicates which POT-profile is active. 0 means the even
      POT-profile is active, 1 means the odd POT-profile is active.

   Length:  Length of the variable metadata, in 4-octet words.  Here the
      length is 4.

   Random:  64-bit Per-packet Random number.

   Cumulative:  64-bit Cumulative that is updated by the Service
      Functions.




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7.  In-situ OAM Metadata Transport in Segment Routing

7.1.  In-situ OAM in SR with IPv6 Transport

   Similar to NSH, a service chain or path defined using Segment Routing
   for IPv6 can be verified using the in-situ OAM "Proof of Transit"
   approach.  The Segment Routing Header (SRH) for IPv6 offers the
   ability to transport TLV structured data, similar to what NSH does
   (see [I-D.ietf-6man-segment-routing-header]).  In an domain where in-
   situ OAM is used, insertion of the in-situ OAM data is enabled at the
   required edge nodes (i.e. at the in-situ OAM encapsulating/
   decapsulating nodes) by means of configuration.

   A new "POT TLV" is defined for the SRH which is to carry proof of
   transit in situ OAM data.

     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
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |      Type     |    Length     |   RESERVED    |F|   Flags     |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
    |                           Random                              |  |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  P
    |                        Random(contd.)                         |  O
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  T
    |                         Cumulative                            |  |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
    |                     Cumulative (contd.)                       |  |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+

   Type:  To be assigned by IANA.

   Length:  18.

   RESERVED:  8 bits.  SHOULD be unset on transmission and MUST be
      ignored on receipt.

   F: 1 bit.  Indicates which POT-profile is active. 0 means the even
      POT-profile is active, 1 means the odd POT-profile is active.

   Flags:  8 bits.  No flags are defined in this document.

   Random:  64-bit per-packet random number.

   Cumulative:  64-bit cumulative value that is updated at specific
      nodes that form the service path to be verified.





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7.2.  In-situ OAM in SR with MPLS Transport

   In-situ OAM "Proof of Transit" data can also be carried as part of
   the MPLS label stack.  Details will be addressed in a future version
   of this document.

8.  IANA Considerations

   IANA considerations will be added in a future version of this
   document.

9.  Manageability Considerations

   Manageability considerations will be addressed in a later version of
   this document..

10.  Security Considerations

   Security considerations will be addressed in a later version of this
   document.  For a discussion of security requirements of in-situ OAM,
   please refer to [I-D.brockners-inband-oam-requirements].

11.  Acknowledgements

   The authors would like to thank Eric Vyncke, Nalini Elkins, Srihari
   Raghavan, Ranganathan T S, Karthik Babu Harichandra Babu, Akshaya
   Nadahalli, Stefano Previdi, Hemant Singh, Erik Nordmark, LJ Wobker,
   and Andrew Yourtchenko for the comments and advice.  For the IPv6
   encapsulation, this document leverages and builds on top of several
   concepts described in [I-D.kitamura-ipv6-record-route].  The authors
   would like to acknowledge the work done by the author Hiroshi
   Kitamura and people involved in writing it.

12.  References

12.1.  Normative References

   [I-D.brockners-inband-oam-requirements]
              Brockners, F., Bhandari, S., Dara, S., Pignataro, C.,
              Gredler, H., Leddy, J., and S. Youell, "Requirements for
              In-band OAM", draft-brockners-inband-oam-requirements-01
              (work in progress), July 2016.

12.2.  Informative References

   [FD.io]    "Fast Data Project: FD.io", <https://fd.io/>.





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   [I-D.brockners-inband-oam-data]
              Brockners, F., Bhandari, S., Pignataro, C., Gredler, H.,
              Leddy, J., and S. Youell, "Data Formats for In-band OAM",
              draft-brockners-inband-oam-data-01 (work in progress),
              July 2016.

   [I-D.brockners-proof-of-transit]
              Brockners, F., Bhandari, S., Dara, S., Pignataro, C.,
              Leddy, J., and S. Youell, "Proof of Transit", draft-
              brockners-proof-of-transit-01 (work in progress), July
              2016.

   [I-D.ietf-6man-segment-routing-header]
              Previdi, S., Filsfils, C., Field, B., Leung, I., Linkova,
              J., Aries, E., Kosugi, T., Vyncke, E., and D. Lebrun,
              "IPv6 Segment Routing Header (SRH)", draft-ietf-6man-
              segment-routing-header-02 (work in progress), September
              2016.

   [I-D.ietf-ippm-6man-pdm-option]
              Elkins, N., Hamilton, R., and m. mackermann@bcbsm.com,
              "IPv6 Performance and Diagnostic Metrics (PDM) Destination
              Option", draft-ietf-ippm-6man-pdm-option-06 (work in
              progress), September 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.ietf-sfc-nsh]
              Quinn, P. and U. Elzur, "Network Service Header", draft-
              ietf-sfc-nsh-10 (work in progress), September 2016.

   [I-D.ietf-spring-segment-routing]
              Filsfils, C., Previdi, S., Decraene, B., Litkowski, S.,
              and R. Shakir, "Segment Routing Architecture", draft-ietf-
              spring-segment-routing-09 (work in progress), July 2016.

   [I-D.kitamura-ipv6-record-route]
              Kitamura, H., "Record Route for IPv6 (PR6) Hop-by-Hop
              Option Extension", draft-kitamura-ipv6-record-route-00
              (work in progress), November 2000.

   [I-D.penno-sfc-trace]
              Penno, R., Quinn, P., Pignataro, C., and D. Zhou,
              "Services Function Chaining Traceroute", draft-penno-sfc-
              trace-03 (work in progress), September 2015.



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   [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>.

   [RFC7665]  Halpern, J., Ed. and C. Pignataro, Ed., "Service Function
              Chaining (SFC) Architecture", RFC 7665, DOI 10.17487/
              RFC7665, October 2015,
              <http://www.rfc-editor.org/info/rfc7665>.

Authors' Addresses

   Frank Brockners
   Cisco Systems, Inc.
   Hansaallee 249, 3rd Floor
   DUESSELDORF, NORDRHEIN-WESTFALEN  40549
   Germany

   Email: fbrockne@cisco.com


   Shwetha Bhandari
   Cisco Systems, Inc.
   Cessna Business Park, Sarjapura Marathalli Outer Ring Road
   Bangalore, KARNATAKA 560 087
   India

   Email: shwethab@cisco.com


   Carlos Pignataro
   Cisco Systems, Inc.
   7200-11 Kit Creek Road
   Research Triangle Park, NC  27709
   United States

   Email: cpignata@cisco.com


   Hannes Gredler
   RtBrick Inc.

   Email: hannes@rtbrick.com








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   John Leddy
   Comcast

   Email: John_Leddy@cable.comcast.com


   Stephen Youell
   JP Morgan Chase
   25 Bank Street
   London  E14 5JP
   United Kingdom

   Email: stephen.youell@jpmorgan.com


   Tal Mizrahi
   Marvell
   6 Hamada St.
   Yokneam  20692
   Israel

   Email: talmi@marvell.com


   David Mozes
   Mellanox Technologies Ltd.

   Email: davidm@mellanox.com


   Petr Lapukhov
   Facebook
   1 Hacker Way
   Menlo Park, CA  94025
   US

   Email: petr@fb.com


   Remy Chang
   Barefoot Networks
   2185 Park Boulevard
   Palo Alto, CA  94306
   US







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