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Versions: 00

Network Working Group                                       F. Brockners
Internet-Draft                                               S. Bhandari
Intended status: Standards Track                             V. Govindan
Expires: May 3, 2018                                        C. Pignataro
                                                                   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, 2017


               Geneve encapsulation for In-situ OAM Data
                  draft-brockners-nvo3-ioam-geneve-00

Abstract

   In-situ Operations, Administration, and Maintenance (IOAM) records
   operational and telemetry information in the packet while the packet
   traverses a path between two points in the network.  This document
   outlines how IOAM data fields are encapsulated in Geneve.

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 May 3, 2018.



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Copyright Notice

   Copyright (c) 2017 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  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions . . . . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Requirement Language  . . . . . . . . . . . . . . . . . .   3
     2.2.  Abbreviations . . . . . . . . . . . . . . . . . . . . . .   3
   3.  IOAM Data Field Encapsulation in Geneve . . . . . . . . . . .   3
     3.1.  IOAM Trace Data in Geneve . . . . . . . . . . . . . . . .   3
     3.2.  IOAM POT Data in Geneve . . . . . . . . . . . . . . . . .   7
     3.3.  IOAM Edge-to-Edge Data in Geneve  . . . . . . . . . . . .   8
   4.  Discussion of the encapsulation approach  . . . . . . . . . .   9
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  10
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  11
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  11
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  11
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  12

1.  Introduction

   In-situ OAM (IOAM) records OAM information within the packet while
   the packet traverses a particular network domain.  The term "in-situ"
   refers to the fact that the IOAM data fields are added to the data
   packets rather than is being sent within packets specifically
   dedicated to OAM.  This document defines how IOAM data fields are
   transported as part of the Geneve [I-D.ietf-nvo3-geneve]
   encapsulation.  The IOAM data fields are defined in
   [I-D.ietf-ippm-ioam-data].







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2.  Conventions

2.1.  Requirement 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].

2.2.  Abbreviations

   Abbreviations used in this document:

   IOAM:      In-situ Operations, Administration, and Maintenance

   MTU:       Maximum Transmit Unit

   OAM:       Operations, Administration, and Maintenance

   POT:       Proof of Transit

   Geneve:    Generic Network Virtualization Encapsulation

3.  IOAM Data Field Encapsulation in Geneve

   For encapsulating IOAM data fields into Geneve [I-D.ietf-nvo3-geneve]
   the different IOAM data fields are included in the Geneve header
   using tunnel options.  IOAM data fields use a tunnel option class
   which includes the different types of IOAM data, including trace
   data, proof-of-transit data, and edge-to-edge data.  In an
   administrative domain where IOAM is used, insertion of the IOAM
   tunnel option(s) in Geneve is enabled at the Geneve tunnel endpoints
   which also serve as IOAM encapsulating/decapsulating nodes by means
   of configuration.  The Geneve header is defined in
   [I-D.ietf-nvo3-geneve].  IOAM specific fields for Geneve are defined
   in this document.

3.1.  IOAM Trace Data in Geneve

   IOAM tracing data represents data that is inserted at nodes that a
   packet traverses.  To allow for optimal implementations in both
   software as well as hardware forwarders, two different ways to
   encapsulate IOAM data are defined: "Pre-allocated" and "incremental".
   See [I-D.ietf-ippm-ioam-data] for details on IOAM tracing and the
   pre-allocated and incremental IOAM trace options.

   The packet formats of the pre-allocated IOAM trace and incremental
   IOAM trace when encapsulated in Geneve are defined as 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        |  |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Hdr
 |        Virtual Network Identifier (VNI)       |    Reserved   |  |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+
 |  Option Class = IOAM_Trace    |Type (prealloc)|R|R|R| Length  |  |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IOAM
 |         IOAM-Trace-Type       |NodeLen|  Flags  | Octets-left | Trace
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
 |                                                               |  |
 |                        node data list [0]                     | IOAM
 |                                                               |  |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  D
 |                                                               |  a
 |                        node data list [1]                     |  t
 |                                                               |  a
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 ~                             ...                               ~  S
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  p
 |                                                               |  a
 |                        node data list [n-1]                   |  c
 |                                                               |  e
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
 |                                                               |  |
 |                        node data list [n]                     |  |
 |                                                               |  |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-<--+
 |                                                               |
 |                                                               |
 |                     Payload + Padding (L2/L3/ESP/...)         |
 |                                                               |
 |                                                               |
 |                                                               |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 Pre-allocated Trace Option Data MUST be 4-octet aligned.

    Figure 1: IOAM Pre-allocated Trace Option Format as a Geneve Tunnel
                                  Option











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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        |  |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Hdr
 |        Virtual Network Identifier (VNI)       |    Reserved   |  |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+
 |  Option Class = IOAM_Trace    |  Type (incr.) |R|R|R| Length  |  |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IOAM
 |        IOAM-Trace-Type        |NodeLen|  Flags  | Max Length  | Trace
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+
 |                                                               |  |
 |                        node data list [0]                     | IOAM
 |                                                               |  |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  D
 |                                                               |  a
 |                        node data list [1]                     |  t
 |                                                               |  a
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 ~                             ...                               ~  S
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  p
 |                                                               |  a
 |                        node data list [n-1]                   |  c
 |                                                               |  e
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
 |                                                               |  |
 |                        node data list [n]                     |  |
 |                                                               |  |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-<--+
 |                                                               |
 |                                                               |
 |                     Payload + Padding (L2/L3/ESP/...)         |
 |                                                               |
 |                                                               |
 |                                                               |
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 IOAM Incremental Trace Option Data MUST be 4-octet aligned.

     Figure 2: IOAM Incremental Trace Option Format as a Geneve Tunnel
                                  Option

   The IOAM Trace header consists of 8 octets, as illustrated in
   Figure 1 and Figure 2.  The first 4 octets are the Geneve Tunnel
   Option header [I-D.ietf-nvo3-geneve].  The next 4 octets are the
   trace option header; its format is defined in
   [I-D.ietf-ippm-ioam-data], and is described here for the sake of
   clarity.




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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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Option Class = IOAM_Trace    |      Type     |R|R|R| Length  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                  Figure 3: Geneve Tunnel Option for IOAM

   The fields of the Geneve tunnel option are as follows:

   Option Class:  16-bit unsigned integer that determines the IOAM
      option class.  The value is from the IANA registry setup for
      Geneve option classes as defined in [I-D.ietf-nvo3-geneve].

   Type:  8-bit unsigned integer defining IOAM header type.  Two values
      are defined here: IOAM_TRACE_Preallocated and
      IOAM_Trace_Incremental.

   R (3 bits):  Option control flags reserved for future use.  MUST be
      zero on transmission and ignored on receipt.

   Length:  5-bit unsigned integer.  Length of the IOAM HDR in 4-octet
      units.

   The fields of the trace option header [I-D.ietf-ippm-ioam-data] are
   as follows:

   IOAM-Trace-Type:  16-bit identifier of IOAM Trace Type as defined in
      [I-D.ietf-ippm-ioam-data] IOAM-Trace-Types.

   Node Data Length:  4-bit unsigned integer as defined in
      [I-D.ietf-ippm-ioam-data].

   Flags:  5-bit field as defined in [I-D.ietf-ippm-ioam-data].

   Octets-left:  7-bit unsigned integer as defined in
      [I-D.ietf-ippm-ioam-data].

   Maximum-length:  7-bit unsigned integer as defined in
      [I-D.ietf-ippm-ioam-data].

   Node data List [n]:  Variable-length field as defined in
      [I-D.ietf-ippm-ioam-data].








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3.2.  IOAM POT Data in Geneve

   IOAM proof of transit (POT, see also
   [I-D.brockners-proof-of-transit]) offers a means to verify that a
   packet has traversed a defined set of nodes.  IOAM POT data fields
   are encapsulated in Geneve as follows:

   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        |  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Hdr
  |        Virtual Network Identifier (VNI)       |    Reserved   |  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+
  |     Option Class = IOAM_POT   |     Type    |P|R|R|R| Length  |  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IOAM
  |                           Random                              |  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  P
  |                        Random(contd.)                         |  O
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  T
  |                         Cumulative                            |  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  |
  |                    Cumulative (contd.)                        |  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+

     Figure 4: IOAM POT Header Following using a Geneve Tunnel Option

   The first 4 octets of the IOAM POT are the Geneve tunnel option
   header (Figure 5), which includes the following fields:

   Option Class:  16-bit unsigned integer that determines the IOAM_POT
      option class.The value is from the IANA registry setup for Geneve
      option classes as defined in [I-D.ietf-nvo3-geneve].

   Type:  7-bit identifier of a particular POT variant that specifies
      the POT data that is to be included as defined in
      [I-D.ietf-ippm-ioam-data].

   Profile to use (P):  1-bit as defined in [I-D.ietf-ippm-ioam-data]
      IOAM POT Option.

   R (3 bits):  Option control flags reserved for future use.  MUST be
      zero on transmission and ignored on receipt.

   Length:  5-bit unsigned integer.  Length of the IOAM HDR in 4-octet
      units.





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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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     Option Class = IOAM_POT   |     Type    |P|R|R|R| Length  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                Figure 5: Geneve Tunnel Option for IOAM POT

   The rest of the fields in the POT option [I-D.ietf-ippm-ioam-data]
   are as follows:

   Random:  64-bit Per-packet random number.

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

3.3.  IOAM Edge-to-Edge Data in Geneve

   The IOAM edge-to-edge option is to carry data that is added by the
   IOAM encapsulating node and interpreted by the IOAM decapsulating
   node.  IOAM specific fields to encapsulate IOAM Edge-to-Edge data
   fields are defined as follows:

   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        |  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Hdr
  |        Virtual Network Identifier (VNI)       |    Reserved   |  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+
  |      Option Class = IOAM_E2E  |    Type       |R|R|R| Length  |  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IOAM
  |      E2E Option data field determined by IOAM-E2E-Type        |  |
  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+


         Figure 6: IOAM Edge-to-Edge using a Geneve Tunnel Option

   The first 4 octets of the IOAM E2E option are the Geneve tunnel
   option header (Figure 5), which includes the following fields:

   Option Class  16-bit unsigned integer that determines the IOAM_E2E
      option class.The value is from the IANA registry setup for Geneve
      option classes as defined in [I-D.ietf-nvo3-geneve].

   Type:  8-bit identifier of a particular E2E variant that specifies
      the E2E data that is included as defined in
      [I-D.ietf-ippm-ioam-data].



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   R (3 bits):  Option control flags reserved for future use.  MUST be
      zero on transmission and ignored on receipt.

   Length:  5-bit unsigned integer.  Length of the IOAM HDR in 4-octet
      units.

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |      Option Class = IOAM_E2E  |    Type       |R|R|R| Length  |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                Figure 7: Geneve Tunnel Option for IOAM E2E

   The rest of the E2E option [I-D.ietf-ippm-ioam-data] consists of:

   E2E Option data field:  Variable length field as defined in
      [I-D.ietf-ippm-ioam-data] IOAM E2E Option.

4.  Discussion of the encapsulation approach

   This section is to support the working group discussion in selecting
   the most appropriate approach for encapsulating IOAM data fields in
   Geneve.

   An encapsulation of IOAM data fields in Geneve should be friendly to
   an implementation in both hardware as well as software forwarders and
   support a wide range of deployment cases, including large networks
   that desire to leverage multiple IOAM data fields at the same time.

      Hardware and software friendly implementation: Hardware forwarders
      benefit from an encapsulation that minimizes iterative look-ups of
      fields within the packet: Any operation which looks up the value
      of a field within the packet, based on which another lookup is
      performed, consumes additional gates and time in an implementation
      - both of which are desired to be kept to a minimum.  This means
      that flat TLV structures are to be preferred over nested TLV
      structures.  IOAM data fields are grouped into three option
      categories: Trace, proof-of-transit, and edge-to-edge.  Each of
      these three options defines a TLV structure.  A hardware-friendly
      encapsulation approach avoids grouping these three option
      categories into yet another TLV structure, but would rather carry
      the options as a serial sequence.

      Total length of the IOAM data fields: The total length of IOAM
      data can grow quite large in case multiple different IOAM data
      fields are used and large path-lengths need to be considered.  If
      for example an operator would consider using the IOAM trace option



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      and capture node-id, app_data, egress/ingress interface-id,
      timestamp seconds, timestamps nanoseconds at every hop, then a
      total of 20 octets would be added to the packet at every hop.  In
      case this particular deployment would have a maximum path length
      of 15 hops in the IOAM domain, then a maximum of 300 octets of
      IOAM data were to be encapsulated in the packet.

   Concerns with the current encapsulation approach:

      Hardware support: Using Geneve tunnel options to encapsulate IOAM
      data fields leads to a nested TLV structure.  Each IOAM data field
      option (trace, proof-of-transit, and edge-to-edge) represents a
      type, with the different IOAM data fields being TLVs within this
      the particular option type.  Nested TLVs require iterative look-
      ups, a fact that creates potential challenges for implementations
      in hardware.  It would be desirable to offer a way to encapsulate
      IOAM in a way that keeps TLV nesting to a minimum.

      Length: Geneve tunnel option length is a 5-bit field in the
      current specification [I-D.ietf-nvo3-geneve] resulting in a
      maximum option length of 128 (2^5 x 4) octets which constrains the
      use of IOAM to either small domains or a few IOAM data fields
      only.  Support for large domains with a variety of IOAM data
      fields would be desirable.

5.  IANA Considerations

   IANA is requested to allocate a Geneve "option class" numbers for the
   following IOAM types:

                 +---------------+-------------+---------------+
                 | Option Class  | Description | Reference     |
                 +---------------+-------------+---------------+
                 | x             | IOAM_Trace  | This document |
                 | y             | IOAM_POT    | This document |
                 | z             | IOAM_E2E    | This document |
                 +---------------+-------------+---------------+


6.  Security Considerations

   The security considerations of Geneve are discussed in
   [I-D.ietf-nvo3-geneve], and the security considerations of IOAM in
   general are discussed in [I-D.ietf-ippm-ioam-data].

   IOAM is considered a "per domain" feature, where one or several
   operators decide on leveraging and configuring IOAM according to
   their needs.  Still, operators need to properly secure the IOAM



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   domain to avoid malicious configuration and use, which could include
   injecting malicious IOAM packets into a domain.

7.  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.

8.  References

8.1.  Normative References

   [ETYPES]   "IANA Ethernet Numbers",
              <https://www.iana.org/assignments/ethernet-numbers/
              ethernet-numbers.xhtml>.

   [I-D.brockners-inband-oam-requirements]
              Brockners, F., Bhandari, S., Dara, S., Pignataro, C.,
              Gredler, H., Leddy, J., Youell, S., Mozes, D., Mizrahi,
              T., <>, P., and r. remy@barefootnetworks.com,
              "Requirements for In-situ OAM", draft-brockners-inband-
              oam-requirements-03 (work in progress), March 2017.

   [I-D.ietf-ippm-ioam-data]
              Brockners, F., Bhandari, S., Pignataro, C., Gredler, H.,
              Leddy, J., Youell, S., Mizrahi, T., Mozes, D., Lapukhov,
              P., Chang, R., and d. daniel.bernier@bell.ca, "Data Fields
              for In-situ OAM", draft-ietf-ippm-ioam-data-00 (work in
              progress), September 2017.

   [I-D.ietf-nvo3-geneve]
              Gross, J., Ganga, I., and T. Sridhar, "Geneve: Generic
              Network Virtualization Encapsulation", draft-ietf-
              nvo3-geneve-05 (work in progress), September 2017.

   [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>.

   [RFC2784]  Farinacci, D., Li, T., Hanks, S., Meyer, D., and P.
              Traina, "Generic Routing Encapsulation (GRE)", RFC 2784,
              DOI 10.17487/RFC2784, March 2000, <https://www.rfc-
              editor.org/info/rfc2784>.





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   [RFC3232]  Reynolds, J., Ed., "Assigned Numbers: RFC 1700 is Replaced
              by an On-line Database", RFC 3232, DOI 10.17487/RFC3232,
              January 2002, <https://www.rfc-editor.org/info/rfc3232>.

8.2.  Informative References

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

   [I-D.brockners-proof-of-transit]
              Brockners, F., Bhandari, S., Dara, S., Pignataro, C.,
              Leddy, J., Youell, S., Mozes, D., and T. Mizrahi, "Proof
              of Transit", draft-brockners-proof-of-transit-03 (work in
              progress), March 2017.

   [RFC7665]  Halpern, J., Ed. and C. Pignataro, Ed., "Service Function
              Chaining (SFC) Architecture", RFC 7665,
              DOI 10.17487/RFC7665, October 2015, <https://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


   Vengada Prasad Govindan
   Cisco Systems, Inc.

   Email: venggovi@cisco.com








Brockners, et al.          Expires May 3, 2018                 [Page 12]


Internet-Draft      In-situ OAM Geneve encapsulation        October 2017


   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


   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








Brockners, et al.          Expires May 3, 2018                 [Page 13]


Internet-Draft      In-situ OAM Geneve encapsulation        October 2017


   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





































Brockners, et al.          Expires May 3, 2018                 [Page 14]


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