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Extended OAM to Carry In-situ OAM Configuration Data
draft-xiao-ippm-ioam-conf-state-01

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This is an older version of an Internet-Draft whose latest revision state is "Replaced".
Authors Xiao Min , Greg Mirsky
Last updated 2018-09-12
Replaced by draft-ietf-ippm-ioam-conf-state, RFC 9359
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draft-xiao-ippm-ioam-conf-state-01
IPPM Working Group                                                X. Min
Internet-Draft                                                 G. Mirsky
Intended status: Standards Track                                     ZTE
Expires: March 16, 2019                               September 12, 2018

          Extended OAM to Carry In-situ OAM Configuration Data
                   draft-xiao-ippm-ioam-conf-state-01

Abstract

   This document describes an extension for OAM packet such as IP Ping
   (ICMP [RFC0792] or ICMPv6 [RFC4443]) and MPLS LSP Ping [RFC8029],
   which can be used within an IOAM domain, allowing the IOAM
   encapsulating node to acquire IOAM configuration data of each IOAM
   transit node and/or IOAM decapsulating node easily and dynamically.

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
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   Internet-Drafts are draft documents valid for a maximum of six months
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   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on March 16, 2019.

Copyright Notice

   Copyright (c) 2018 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
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   described in the Simplified BSD License.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Conventions Used in This Document . . . . . . . . . . . .   3
       1.1.1.  Terminology . . . . . . . . . . . . . . . . . . . . .   3
       1.1.2.  Requirements Language . . . . . . . . . . . . . . . .   3
   2.  IOAM Configuration Data Formats . . . . . . . . . . . . . . .   3
     2.1.  IOAM Configuration Data TLV . . . . . . . . . . . . . . .   3
       2.1.1.  IOAM Tracing Configuration Data sub-TLV . . . . . . .   4
       2.1.2.  IOAM Proof of Transit Configuration Data sub-TLV  . .   6
       2.1.3.  IOAM Edge-to-Edge Configuration Data sub-TLV  . . . .   7
       2.1.4.  IOAM End-of-Domain sub-TLV  . . . . . . . . . . . . .   8
   3.  Operational Guide . . . . . . . . . . . . . . . . . . . . . .   9
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .   9
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  10
   7.  Normative References  . . . . . . . . . . . . . . . . . . . .  10
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  11

1.  Introduction

   The Data Fields for In-situ OAM (IOAM) [I-D.ietf-ippm-ioam-data]
   defines data fields for IOAM which records OAM information within the
   packet while the packet traverses a particular network domain, which
   is called an IOAM domain.  IOAM can be used to complement OAM
   mechanisms based on, e.g., ICMP or other types of probe packets, and
   IOAM mechanisms can be leveraged where mechanisms using, e.g., ICMP
   do not apply or do not offer the desired results.

   As specified in [I-D.ietf-ippm-ioam-data], within the IOAM-domain,
   the IOAM data may be updated by network nodes that the packet
   traverses.  The device which adds an IOAM data container to the
   packet to capture IOAM data is called the "IOAM encapsulating node",
   whereas the device which removes the IOAM data container is referred
   to as the "IOAM decapsulating node".  Nodes within the domain which
   are aware of IOAM data and read and/or write or process the IOAM data
   are called "IOAM transit nodes".  Both the IOAM encapsulating node
   and the decapsulating node are referred to as domain edge devices,
   which can be hosts or network devices.

   In order to add accurate IOAM data container to the packet, the IOAM
   encapsulating node needs to know IOAM configurations at the IOAM
   transit nodes in a whole, e.g., how many IOAM transit nodes will add
   tracing data and what kinds of data fields will be added.  Static
   configuration at the IOAM encapsulating node is a way to address
   this, but it's uneasy and inflexible, especially when the IOAM
   encapsulating node is a host.  This document describes an extension
   for OAM packet such as IP Ping (ICMP [RFC0792] or ICMPv6 [RFC4443])

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   and MPLS LSP Ping [RFC8029], which can be used within an IOAM domain,
   allowing the IOAM encapsulating node to acquire IOAM configuration
   data of each IOAM transit node and/or IOAM decapsulating node easily
   and dynamically.

1.1.  Conventions Used in This Document

1.1.1.  Terminology

   E2E: Edge to Edge

   ICMP: Internet Control Message Protocol

   IOAM: In-situ Operations, Administration, and Maintenance

   LSP: Label Switched Path

   MPLS: Multi-Protocol Label Switching

   MTU: Maximum Transmission Unit

   NTP: Network Time Protocol

   OAM: Operations, Administration, and Maintenance

   POSIX: Portable Operating System Interface

   POT: Proof of Transit

   PTP: Precision Time Protocol

   TTL: Time to Live

1.1.2.  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.

2.  IOAM Configuration Data Formats

2.1.  IOAM Configuration Data TLV

   IOAM Configuration Data uses TLV (Type-Length-Value tuple) which have
   the following format:

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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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Type = IOAM Configuration Data|            Length             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |                             Value                             |
   .                                                               .
   .                                                               .
   .                                                               .
   |                                                               |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                   Figure 1: IOAM Configuration Data TLV

   When this TLV is present in the OAM packet sent by an IOAM
   encapsulating node, it means that the IOAM encapsulating node
   requests the receiving node to reply with its IOAM configuration
   data.  If there is no IOAM configuration data to report by the
   receiving node, then this TLV SHOULD be ignored by the receiving
   node.

   When this TLV is present in the OAM packet sent by an IOAM transit
   node and/or an IOAM decapsulating node, other than an IOAM
   encapsulating node, it means that IOAM function is enabled at this
   node and this TLV contains IOAM configuration data of the sender.
   Note that the IOAM encapsulating node or the IOAM decapsulating node
   can also be an IOAM transit node.

   Type is set to the value (to be assigned by IANA) which indicates
   that it's an IOAM Configuration Data TLV.

   Length is the length of the Value field in octets.  When this TLV is
   present in the OAM packet sent by an IOAM encapsulating node, the
   Length field should be set to 0, and no Value field is included in
   the TLV.  Otherwise, the Length field must not be set to 0.

   Value is zero padded to align to a 4-octet boundary, and sub-TLVs MAY
   be contained in this field.  Based on the data fields for IOAM
   specified in [I-D.ietf-ippm-ioam-data], four new sub-TLVs are defined
   in this document.

2.1.1.  IOAM Tracing Configuration Data sub-TLV

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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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   | Sub-type = Tracing Conf Data  |            Length             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |     IOAM-Trace-Type           |       Egress_if_MTU       |F|R|
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |  Egress_if_id (short or wide format)         ......           |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

             Figure 2: IOAM Tracing Configuration Data Sub-TLV

   When this sub-TLV is present in the IOAM Configuration Data TLV, it
   means that the sending node is an IOAM transit node and IOAM tracing
   function is enabled at this IOAM transit node.

   Sub-type is set to the value (to be assigned by IANA) which indicates
   that it's an IOAM Tracing Configuration Data sub-TLV.

   Length is the length of the sub-TLV's Value field in octets, if
   Egress_if_id in the short format which has 16 bits is used, it MUST
   be set to 6, and if Egress_if_id in the wide format which has 32 bits
   is used, it MUST be set to 8.

   IOAM-Trace-Type field has the same name, length and definition as
   what's specified in both section 4.1.1 of [I-D.ietf-ippm-ioam-data].

   Egress_if_MTU field has 14 bits and specifies the MTU of the egress
   interface out of which the sending node would forward the received
   OAM packet.

   F bit is specified to indicate whether the pre-allocated trace or
   incremental trace is enabled.  F bit is set to 1 when pre-allocated
   trace is enabled and set to 0 when the incremental trace is enabled.
   The meaning and difference of pre-allocated trace and incremental
   trace are described in section 4.1 of [I-D.ietf-ippm-ioam-data].  If
   the IOAM encapsulating node receives different F bit value from
   different IOAM transit node, then the IOAM encapsulating node will
   reserve data space in the IOAM header for the IOAM transit node that
   set F bit to 1, and the IOAM encapsulating node won't reserve data
   space in the IOAM header for the IOAM transit node that set F bit to
   0.

   R bit is reserved for future standardization.

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   Egress_if_id field has 16 bits (in short format) or 32 bits (in wide
   format) and specifies the identifier of the egress interface out of
   which the sending node would forward the received OAM packet.

2.1.2.  IOAM Proof of Transit Configuration Data sub-TLV

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Sub-type = POT Conf Data    |            Length             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |IOAM-POT-Type|P|SoR|              Reserved                     |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        Figure 3: IOAM Proof of Transit Configuration Data Sub-TLV

   When this sub-TLV is present in the IOAM Configuration Data TLV, it
   means that the sending node is an IOAM transit node and IOAM proof of
   transit function is enabled at this IOAM transit node.

   Sub-type is set to the value (to be assigned by IANA) which indicates
   that it's an IOAM Proof of Transit Configuration Data sub-TLV.

   Length is the length of the sub-TLV's Value field in octets, and MUST
   be set to 4.

   IOAM-POT-Type field and P bit have the same name, length and
   definition as what's specified in section 4.2 of
   [I-D.ietf-ippm-ioam-data].  If the IOAM encapsulating node receives
   IOAM-POT-Type and/or P bit values from an IOAM transit node that are
   different from its own, then the IOAM encapsulating node MAY choose
   to abandon the proof of transit function or to select one kind of
   IOAM-POT-Type and P bit, it's based on the policy applied to the IOAM
   encapsulating node.

   SoR field has two bits which means the size of "Random" and
   "Cumulative" data, which are specified in section 4.2 of
   [I-D.ietf-ippm-ioam-data].  This document defines SoR as follow:

      0b00 means 64-bit "Random" and 64-bit "Cumulative" data.

      0b01~0b11: Reserved for future standardization

   Reserved field is used for future standardization.

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2.1.3.  IOAM Edge-to-Edge Configuration Data sub-TLV

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Sub-type = E2E Conf Data    |            Length             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |         IOAM-E2E-Type         |TSF|TSL|       Reserved        |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

          Figure 4: IOAM Edge to Edge Configuration Data Sub-TLV

   When this sub-TLV is present in the IOAM Configuration Data TLV, it
   means that the sending node is an IOAM decapsulating node and IOAM
   edge to edge function is enabled at this IOAM decapsulating node.
   That is to say, if the IOAM encapsulating node receives this sub-TLV,
   the IOAM encapsulating node can determine that the node which sends
   this sub-TLV is an IOAM decapsulating node.

   Sub-type is set to the value (to be assigned by IANA) which indicates
   that it's an IOAM Edge to Edge Configuration Data sub-TLV.

   Length is the length of the sub-TLV's Value field in octets, and MUST
   be set to 4.

   IOAM-E2E-Type field has the same name, length and definition as
   what's specified in section 4.3 of [I-D.ietf-ippm-ioam-data].

   TSF field specifies the timestamp format used by the sending node.
   This document defines TSF as follow:

      0b00: PTP timestamp format

      0b01: NTP timestamp format

      0b10: POSIX timestamp format

      0b11: Reserved for future standardization

   TSL field specifies the timestamp length used by the sending node.
   This document defines TSL as follow:

      When TSF field is set to 0b00 which indicates PTP timestamp
      format:

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      0b00: 64-bit PTPv1 timestamp as defined in IEEE1588-2008
      [IEEE1588v2]

      0b01: 80-bit PTPv2 timestamp as defined in IEEE1588-2008
      [IEEE1588v2]

      0b10~0b11: Reserved for future standardization

      When TSF field is set to 0b01 which indicates NTP timestamp
      format:

      0b00: 32-bit NTP timestamp as defined in NTPv4 [RFC5905]

      0b01: 64-bit NTP timestamp as defined in NTPv4 [RFC5905]

      0b10: 128-bit NTP timestamp as defined in NTPv4 [RFC5905]

      0b11: Reserved for future standardization

      When TSF field is set to 0b10 or 0b11, the TSL field would be
      ignored.

   Reserved field is used for future standardization.

2.1.4.  IOAM End-of-Domain sub-TLV

    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
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
   |   Sub-type = End of Domain    |            Length             |
   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                   Figure 5: IOAM End of Domain Sub-TLV

   When this sub-TLV is present in the IOAM Configuration Data TLV, it
   means that the sending node is an IOAM decapsulating node.  That is
   to say, if the IOAM encapsulating node receives this sub-TLV, the
   IOAM encapsulating node can determine that the node which sends this
   sub-TLV is an IOAM decapsulating node.  When the IOAM Edge-to-Edge
   Configuration Data sub-TLV is present in the IOAM Configuration Data
   TLV sent by the IOAM decapsulating node, the IOAM End-of-Domain sub-
   TLV doesn't need to be present in the same IOAM Configuration Data
   TLV, otherwise the End-of-Domain sub-TLV MUST be present in the IOAM
   Configuration Data TLV sent by the IOAM decapsulating node.  Since
   both the IOAM Edge-to-Edge Configuration Data sub-TLV and the IOAM
   End-of-Domain sub-TLV can be used to indicate that the sending node

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   is an IOAM decapsulating node, it's recommended to include only the
   IOAM Edge-to-Edge Configuration Data sub-TLV if IOAM edge to edge
   function is enabled at this IOAM decapsulating node.

   Length is the length of the sub-TLV's Value field in octets, and MUST
   be set to 0.

3.  Operational Guide

   Once the IOAM encapsulating node is triggered to acquire IOAM
   configuration data of each IOAM transit node and/or IOAM
   decapsulating node, the IOAM encapsulating node will send a batch of
   OAM probe packets that include the IOAM Configuration Data TLV, first
   with TTL equal to 1 to reach the nearest node which may be an IOAM
   transit node or not, then with TTL equal to 2 to reach the second
   nearest node which also may be an IOAM transit node or not, on the
   analogy of this to increase 1 to TTL every time the IOAM
   encapsulating node sends a new OAM probe packet, until the IOAM
   encapsulating node receives OAM probe reply packet sent by the IOAM
   decapsulating node, which must contain the IOAM Configuration Data
   TLV including the IOAM Edge-to-Edge Configuration Data sub-TLV or the
   IOAM End-of-Domain sub-TLV.

   The IOAM encapsulating node may be triggered by the device
   administrator, the network management, the network controller, or
   even the live user traffic, and the specific triggering mechanisms
   are outside the scope of this document.

   Each IOAM transit node and/or IOAM decapsulating node that receives
   an OAM probe packet containing the IOAM Configuration Data TLV will
   send an OAM probe reply packet to the IOAM encapsulating node, and
   within the OAM probe reply packet, there must be an IOAM
   Configuration Data TLV containing one or more sub-TLVs.  The IOAM
   Configuration Data TLV contained in the OAM probe packet will be
   ignored by the receiving node that is unaware of IOAM.

4.  Security Considerations

   Knowledge of the state of the IOAM domain may be considered
   confidential.  Implementations SHOULD provide a means of filtering
   the addresses to which echo reply messages, ICMP/ICMPv6 or MPLS LSP
   Ping, may be sent.

5.  IANA Considerations

   To be added.

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   Editor's Note: For different OAM packet such as IP Ping (ICMP
   [RFC0792] or ICMPv6 [RFC4443]) and MPLS LSP Ping [RFC8029] different
   Type and Sub-type will be requested from IANA.

6.  Acknowledgements

   To be added.

7.  Normative References

   [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., daniel.bernier@bell.ca, d., and J. Lemon,
              "Data Fields for In-situ OAM", draft-ietf-ippm-ioam-
              data-03 (work in progress), June 2018.

   [IEEE1588v2]
              Institute of Electrical and Electronics Engineers, "IEEE
              Std 1588-2008 - IEEE Standard for a Precision Clock
              Synchronization Protocol for Networked Measurement and
              Control Systems",  IEEE Std 1588-2008, 2008,
              <http://standards.ieee.org/findstds/
              standard/1588-2008.html>.

   [RFC0792]  Postel, J., "Internet Control Message Protocol", STD 5,
              RFC 792, DOI 10.17487/RFC0792, September 1981,
              <https://www.rfc-editor.org/info/rfc792>.

   [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>.

   [RFC4443]  Conta, A., Deering, S., and M. Gupta, Ed., "Internet
              Control Message Protocol (ICMPv6) for the Internet
              Protocol Version 6 (IPv6) Specification", STD 89,
              RFC 4443, DOI 10.17487/RFC4443, March 2006,
              <https://www.rfc-editor.org/info/rfc4443>.

   [RFC5905]  Mills, D., Martin, J., Ed., Burbank, J., and W. Kasch,
              "Network Time Protocol Version 4: Protocol and Algorithms
              Specification", RFC 5905, DOI 10.17487/RFC5905, June 2010,
              <https://www.rfc-editor.org/info/rfc5905>.

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   [RFC8029]  Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N.,
              Aldrin, S., and M. Chen, "Detecting Multiprotocol Label
              Switched (MPLS) Data-Plane Failures", RFC 8029,
              DOI 10.17487/RFC8029, March 2017,
              <https://www.rfc-editor.org/info/rfc8029>.

   [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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