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A YANG Data Model for In-Situ OAM
draft-ietf-ippm-ioam-yang-03

Document Type Active Internet-Draft (ippm WG)
Authors Tianran Zhou , Jim Guichard , Frank Brockners , Srihari Raghavan
Last updated 2022-01-25
Replaces draft-zhou-ippm-ioam-yang
Stream Internet Engineering Task Force (IETF)
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draft-ietf-ippm-ioam-yang-03
IPPM                                                        T. Zhou, Ed.
Internet-Draft                                                    Huawei
Intended status: Standards Track                             J. Guichard
Expires: July 29, 2022                                         Futurewei
                                                            F. Brockners
                                                             S. Raghavan
                                                           Cisco Systems
                                                        January 25, 2022

                   A YANG Data Model for In-Situ OAM
                      draft-ietf-ippm-ioam-yang-03

Abstract

   In-situ Operations, Administration, and Maintenance (IOAM) records
   operational and telemetry information in user packets while the
   packets traverse a path between two points in the network.  This
   document defines a YANG module for the IOAM function.

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 https://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 July 29, 2022.

Copyright Notice

   Copyright (c) 2022 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
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must

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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  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Conventions used in this document . . . . . . . . . . . . . .   3
     2.1.  Tree Diagrams . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Design of the IOAM YANG Data Model  . . . . . . . . . . . . .   3
     3.1.  Overview  . . . . . . . . . . . . . . . . . . . . . . . .   3
     3.2.  Preallocated Tracing Profile  . . . . . . . . . . . . . .   5
     3.3.  Incremental Tracing Profile . . . . . . . . . . . . . . .   6
     3.4.  Direct Export Profile . . . . . . . . . . . . . . . . . .   6
     3.5.  Proof of Transit Profile  . . . . . . . . . . . . . . . .   6
     3.6.  Edge to Edge Profile  . . . . . . . . . . . . . . . . . .   7
   4.  IOAM YANG Module  . . . . . . . . . . . . . . . . . . . . . .   7
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  22
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  23
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  23
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  23
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  23
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  24
   Appendix A.  Examples . . . . . . . . . . . . . . . . . . . . . .  25
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  25

1.  Introduction

   In-situ Operations, Administration, and Maintenance (IOAM)
   [I-D.ietf-ippm-ioam-data] records OAM information within user packets
   while the packets traverse a network.  The data types and data
   formats for IOAM data records have been defined in
   [I-D.ietf-ippm-ioam-data].  The IOAM data can be embedded in many
   protocol encapsulations such as Network Services Header (NSH) and
   IPv6.

   This document defines a data model for IOAM capabilities using the
   YANG data modeling language [RFC7950].  This YANG model supports five
   IOAM options, which are:

   o  Incremental Tracing Option [I-D.ietf-ippm-ioam-data]

   o  Pre-allocated Tracing Option [I-D.ietf-ippm-ioam-data]

   o  Direct Export Option [I-D.ietf-ippm-ioam-direct-export]

   o  Proof of Transit (PoT) Option [I-D.ietf-ippm-ioam-data]

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   o  Edge-to-Edge Option [I-D.ietf-ippm-ioam-data]

2.  Conventions used in this document

   The keywords "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
   BCP14, [RFC2119], [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   The following terms are defined in [RFC7950] and are used in this
   specification:

   o  augment

   o  data model

   o  data node

   The terminology for describing YANG data models is found in
   [RFC7950].

2.1.  Tree Diagrams

   Tree diagrams used in this document follow the notation defined in
   [RFC8340].

3.  Design of the IOAM YANG Data Model

3.1.  Overview

   The IOAM model is organized as list of profiles as shown in the
   following figure.  Each profile associates with one flow and the
   corresponding IOAM information.

   The "ioam-info" is a container for all the read only assistant
   information, so that monitoring systems can interpret the IOAM data.

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   module: ietf-ioam
      +--rw ioam
         +--ro ioam-info
         |  +--ro timestamp-type?        identityref
         |  +--ro available-interface* [if-name]
         |     +--ro if-name    -> if:interfaces/interface/name
         +--rw ioam-profiles
            +--rw admin-config
            |  +--rw enabled?   boolean
            +--rw ioam-profile* [profile-name]
               +--rw profile-name                    string
               +--rw filter
               |  +--rw filter-type?   ioam-filter-type
               |  +--rw ace-name?      -> /acl:acls/acl/aces/ace/name
               +--rw protocol-type?                  ioam-protocol-type
               +--rw incremental-tracing-profile {incremental-trace}?
               |  ...
               +--rw preallocated-tracing-profile {preallocated-trace}?
               |  ...
               +--rw direct-export-profile {direct-export}?
               |  ...
               +--rw pot-profile {proof-of-transit}?
               |  ...
               +--rw e2e-profile {edge-to-edge}?
                  ...

   In the "ioam-profiles", the "enabled" is an administrative
   configuration.  When it is set to true, IOAM configuration is enabled
   for the system.  Meanwhile, the IOAM data-plane functionality is
   enabled.

   The "filter" is used to identify a flow, where the IOAM profile can
   apply.  There may be multiple filter types.  ACL [RFC8519] is a
   common way to specify a flow.  Each IOAM profile can associate with
   an ACE(Access Control Entry).  IOAM actions MUST be driven by the
   accepted packets, when the matched ACE "forwarding" action is
   "accept".

   The IOAM data can be encapsulated into multiple protocols, e.g., IPv6
   [I-D.ietf-ippm-ioam-ipv6-options] and NSH [I-D.ietf-sfc-ioam-nsh].
   The "protocol-type" is used to indicate where the IOAM is applied.
   For example, if the "protocol-type" is IPv6, the IOAM ingress node
   will encapsulate the associated flow with the IPv6-IOAM
   [I-D.ietf-ippm-ioam-ipv6-options] format.

   IOAM data includes five encapsulation types, i.e., incremental
   tracing data, preallocated tracing data, direct export data, proof of
   transit data and end to end data.  In practice, multiple IOAM data

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   types can be encapsulated into the same IOAM header.  The "ioam-
   profile" contains a set of sub-profiles, each of which relates to one
   encapsulation type.  The configured object may not support all the
   sub-profiles.  The supported sub-profiles are indicated by 5 defined
   features, i.e., "incremental-trace", "preallocated-trace", "direct
   export", "proof-of-transit", "edge-to-edge".

3.2.  Preallocated Tracing Profile

   The IOAM tracing data is expected to be collected at every node that
   a packet traverses to ensure visibility into the entire path a packet
   takes within an IOAM domain.  The preallocated tracing option will
   create pre-allocated space for each node to populate its information
   . The "preallocated-tracing-profile" contains the detailed
   information for the preallocated tracing data.  The information
   includes:

   o  enabled: indicates whether the preallocated tracing profile is
      enabled.

   o  node-action: indicates the operation (e.g., encapsulate IOAM
      header, transit the IOAM data, or decapsulate IOAM header) applied
      to the dedicated flow.

   o  use-namespace: indicate the namespace used for the trace types.

   o  trace-type: indicates the per-hop data to be captured by the IOAM
      enabled nodes and included in the node data list.

   o  Loopback mode is used to send a copy of a packet back towards the
      source.

   o  Active mode indicates that a packet is used for active
      measurement.

   +--rw preallocated-tracing-profile {preallocated-trace}?
      +--rw enabled?                boolean
      +--rw node-action?            ioam-node-action
      +--rw trace-types
      |  +--rw use-namespace?   ioam-namespace
      |  +--rw trace-type*      ioam-trace-type
      +--rw enable-loopback-mode?   boolean
      +--rw enable-active-mode?   boolean

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3.3.  Incremental Tracing Profile

   The incremental tracing option contains a variable node data fields
   where each node allocates and pushes its node data immediately
   following the option header.  The "incremental-tracing-profile"
   contains the detailed information for the incremental tracing data.
   The detailed information is the same as the Preallocated Tracing
   Profile, but with one more variable, "max-length", which restricts
   the length of the IOAM header.

   +--rw incremental-tracing-profile {incremental-trace}?
      +--rw enabled?                boolean
      +--rw node-action?            ioam-node-action
      +--rw trace-types
      |  +--rw use-namespace?   ioam-namespace
      |  +--rw trace-type*   ioam-trace-type
      +--rw enable-loopback-mode?   boolean
      +--rw enable-active-mode?   boolean
      +--rw max-length?             uint32

3.4.  Direct Export Profile

   The direct export option is used as a trigger for IOAM nodes to
   export IOAM data to a receiving entity (or entities).  The "direct-
   export-profile" contains the detailed information for the direct
   export data.  The detailed information is the same as the
   Preallocated Tracing Profile, but with one more optional variable,
   "flow-id", which is used to correlate the exported data of the same
   flow from multiple nodes and from multiple packets.

   +--rw direct-export-profile {direct-export}?
      +--rw enabled?                boolean
      +--rw node-action?            ioam-node-action
      +--rw trace-types
      |  +--rw use-namespace?   ioam-namespace
      |  +--rw trace-type*      ioam-trace-type
      +--rw enable-loopback-mode?   boolean
      +--rw enable-active-mode?   boolean
      +--rw flow-id?             uint32

3.5.  Proof of Transit Profile

   The IOAM Proof of Transit data is to support the path or service
   function chain verification use cases.  The "pot-profile" contains
   the detailed information for the proof of transit data. "pot-type"
   indicates a particular POT variant that specifies the POT data that
   is included.  There may be several POT types, which have different
   configuration data.  To align with [I-D.ietf-ippm-ioam-data], this

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   document only defines IOAM POT type 0.  User need to augment this
   module for the configuration of a specifc POT type.

   +--rw pot-profile {proof-of-transit}?
      +--rw enabled?    boolean
      +--rw pot-type?   ioam-pot-type

3.6.  Edge to Edge Profile

   The IOAM edge to edge option is to carry data that is added by the
   IOAM encapsulating node and interpreted by IOAM decapsulating node.
   The "e2e-profile" contains the detailed information for the edge to
   edge data.  The detailed information includes:

   o  enabled: indicates whether the edge to edge profile is enabled.

   o  node-action is the same semantic as in Section 2.2.

   o  use-namespace: indicate the namespace used for the edge to edge
      types.

   o  e2e-type indicates data to be carried from the ingress IOAM node
      to the egress IOAM node.

   +--rw e2e-profile {edge-to-edge}?
      +--rw enabled?       boolean
      +--rw node-action?   ioam-node-action
      +--rw e2e-types
         +--rw use-namespace?   ioam-namespace
         +--rw e2e-type*        ioam-e2e-type

4.  IOAM YANG Module

  <CODE BEGINS> file "ietf-ioam@2022-01-25.yang"
  module ietf-ioam {
    yang-version 1.1;
    namespace "urn:ietf:params:xml:ns:yang:ietf-ioam";
    prefix "ioam";

    import ietf-access-control-list {
      prefix "acl";
      reference
        "RFC 8519: YANG Data Model for Network Access Control
         Lists (ACLs)";
    }

    import ietf-interfaces {
      prefix "if";

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      reference
        "RFC 8343: A YANG Data Model for Interface Management";
    }

    import ietf-lime-time-types {
      prefix "lime";
      reference
        "RFC 8532: Generic YANG Data Model for the Management of
         Operations, Administration, and Maintenance (OAM) Protocols
         That Use Connectionless Communications";
    }

    organization
      "IETF IPPM (IP Performance Metrics) Working Group";

    contact
      "WG Web: <https://datatracker.ietf.org/wg/ippm>
       WG List: <ippm@ietf.org>
       Editor: zhoutianran@huawei.com
       Editor: james.n.guichard@futurewei.com
       Editor: fbrockne@cisco.com
       Editor: srihari@cisco.com";

    description
      "This YANG module specifies a vendor-independent data
       model for the In Situ OAM (IOAM).

      Copyright (c) 2021 IETF Trust and the persons identified as
      authors of the code.  All rights reserved.

      Redistribution and use in source and binary forms, with or
      without modification, is permitted pursuant to, and subject
      to the license terms contained in, the Simplified BSD License
      set forth in Section 4.c of the IETF Trust's Legal Provisions
      Relating to IETF Documents
      (http://trustee.ietf.org/license-info).

      This version of this YANG module is part of RFC XXXX; see the
      RFC itself for full legal notices.";

    revision 2022-01-25 {
      description "First revision.";
      reference "RFC XXXX: A YANG Data Model for In-Situ OAM";
    }

   /*
    * FEATURES
    */

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    feature incremental-trace
    {
      description
        "This feature indicated that the incremental tracing option is
         supported";
      reference "RFC XXXX: Data Fields for In-situ OAM";
    }

    feature preallocated-trace
    {
      description
        "This feature indicated that the preallocated tracing option is
         supported";
      reference "RFC XXXX: Data Fields for In-situ OAM";
    }

    feature direct-export
    {
      description
        "This feature indicated that the direct export option is
         supported";
      reference "RFC XXXX: In-situ OAM Direct Exporting";
    }

    feature proof-of-transit
    {
      description
        "This feature indicated that the proof of transit option is
         supported";
      reference "RFC XXXX: Data Fields for In-situ OAM";
    }

    feature edge-to-edge
    {
      description
        "This feature indicated that the edge to edge option is
         supported";
      reference "RFC XXXX: Data Fields for In-situ OAM";
    }

   /*
    * IDENTITIES
    */
    identity filter {
      description
        "Base identity to represent a filter. A filter is used to
        specify the flow to apply the IOAM profile. ";
    }

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    identity acl-filter {
      base filter;
      description
        "Apply ACL rules to specify the flow.";
    }

    identity protocol {
      description
        "Base identity to represent the carrier protocol. It's used to
         indicate what layer and protocol the IOAM data is embedded.";
    }

    identity ipv6 {
      base protocol;
      description
        "The described IOAM data is embedded in IPv6 protocol.";
      reference "RFC XXXX: In-situ OAM IPv6 Options";
    }

    identity nsh  {
      base protocol;
      description
        "The described IOAM data is embedded in NSH.";
      reference
        "RFC XXXX: Network Service Header (NSH) Encapsulation
         for In-situ OAM (IOAM) Data";
    }

    identity node-action {
      description
        "Base identity to represent the node actions. It's used to
         indicate what action the node will take.";
    }

    identity action-encapsulate {
      base node-action;
      description
        "indicate the node is to encapsulate the IOAM packet";
    }

    identity action-decapsulate {
      base node-action;
      description
        "indicate the node is to decapsulate the IOAM packet";
    }

    identity trace-type {
      description

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        "Base identity to represent trace types";
    }

    identity trace-hop-lim-node-id {
      base trace-type;
      description
        "indicates presence of Hop_Lim and node_id in the
         node data.";
    }

    identity trace-if-id {
      base trace-type;
      description
        "indicates presence of ingress_if_id and egress_if_id
         (short format) in the node data.";
    }

    identity trace-timestamp-seconds {
      base trace-type;
      description
        "indicates presence of timestamp seconds in the node data.";
    }

    identity trace-timestamp-fraction  {
      base trace-type;
      description
        "indicates presence of timestamp fraction in the node data.";
    }

    identity trace-transit-delay {
      base trace-type;
      description
        "indicates presence of transit delay in the node data.";
    }

    identity trace-namespace-data {
      base trace-type;
      description
        "indicates presence of namespace specific data (short format)
         in the node data.";
    }

    identity trace-queue-depth {
      base trace-type;
      description
        "indicates presence of queue depth in the node data.";
    }

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    identity trace-checksum-complement {
      base trace-type;
      description
        "indicates presence of the Checksum Complement node data.";
    }

    identity trace-hop-lim-node-id-wide {
      base trace-type;
      description
        "indicates presence of Hop_Lim and node_id in wide format
         in the node data.";
    }

    identity trace-if-id-wide {
      base trace-type;
      description
        "indicates presence of ingress_if_id and egress_if_id in
         wide format in the node data.";
    }

    identity trace-namespace-data-wide {
      base trace-type;
      description
        "indicates presence of IOAM-Namespace specific data in wide
         format in the node data.";
    }

    identity trace-buffer-occupancy {
      base trace-type;
      description
        "indicates presence of buffer occupancy in the node data.";
    }

    identity trace-opaque-state-snapshot {
      base trace-type;
      description
        "indicates presence of variable length Opaque State Snapshot
         field.";
    }

    identity pot-type {
      description
        "Base identity to represent Proof of Transit (PoT) types.";
    }

    identity pot-type-0 {
      base pot-type;
      description

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        "The IOAM POT Type field value is 0. And POT data is a 16
         Octet field to carry data associated to POT procedures.";
    }

    identity e2e-type {
      description
        "Base identity to represent e2e types";
    }

    identity e2e-seq-num-64 {
      base e2e-type;
      description
        "indicates presence of a 64-bit sequence number.";
    }

    identity e2e-seq-num-32 {
      base e2e-type;
      description
        "indicates presence of a 32-bit sequence number.";
    }

    identity e2e-timestamp-seconds {
      base e2e-type;
      description
        "indicates presence of timestamp seconds representing the time
         at which the packet entered the IOAM-domain";
    }

    identity e2e-timestamp-fraction {
      base e2e-type;
      description
        "indicates presence of timestamp fraction representing the time
         at which the packet entered the IOAM-domain.";
    }

    identity namespace {
      description
        "Base identity to represent the Namespace-ID.";
    }

    identity default-namespace {
      base namespace;
      description
        "The Namespace-ID value of 0x0000 is defined as the
         Default-Namespace-ID and must be known to all the nodes
         implementing IOAM.";
    }

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   /*
    * TYPE DEFINITIONS
    */
    typedef ioam-filter-type {
      type identityref {
        base filter;
      }
      description
        "Specifies a known type of filter.";
    }

    typedef ioam-protocol-type {
      type identityref {
        base protocol;
      }
      description
        "Specifies a known type of carrier protocol for the IOAM data.";
    }

    typedef ioam-node-action {
      type identityref {
        base node-action;
      }
      description
        "Specifies a known type of node action.";
    }

    typedef ioam-trace-type {
      type identityref {
        base trace-type;
      }
      description
        "Specifies a known trace type.";
    }

    typedef ioam-pot-type {
      type identityref {
        base pot-type;
      }
      description
        "Specifies a known pot type.";
    }

    typedef ioam-e2e-type {
      type identityref {
        base e2e-type;
      }
      description

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        "Specifies a known e2e type.";
    }

    typedef ioam-namespace {
      type identityref {
        base namespace;
      }
      description
        "Specifies the supported namespace.";
    }

   /*
    * GROUP DEFINITIONS
    */

    grouping ioam-filter {
      description "A grouping for IOAM filter definition";

      leaf filter-type {
        type ioam-filter-type;
        description "filter type";
      }

      leaf ace-name {
        when "../filter-type = 'ioam:acl-filter'";
        type leafref {
          path "/acl:acls/acl:acl/acl:aces/acl:ace/acl:name";
        }
        description "Access Control Entry name.";
      }
    }

    grouping encap-tracing {
      description
        "A grouping for the generic configuration for
         tracing profile.";

      container trace-types {
        description
          "the list of trace types for encapsulation";

        leaf use-namespace {
          type ioam-namespace;
          description
            "the namespace used for encapsulation";
        }

        leaf-list trace-type {

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          type ioam-trace-type;
          description
            "The trace type is only defined at the encapsulation node.";
        }
      }

      leaf enable-loopback-mode {
        type boolean;
        default false;
        description
          "Loopback mode is used to send a copy of a packet back towards
          the source. The loopback mode is only defined at the
          encapsulation node.";
      }

      leaf enable-active-mode {
        type boolean;
        default false;
        description
          "Active mode indicates that a packet is used for active
           measurement. An IOAM decapsulating node that receives a
           packet with the Active flag set in one of its Trace options
           must terminate the packet.";
      }
    }

    grouping ioam-incremental-tracing-profile {
      description
        "A grouping for incremental tracing profile.";

      leaf node-action {
        type ioam-node-action;
        description "node action";
      }

      uses encap-tracing {
        when "node-action = 'ioam:action-encapsulate'";
      }

      leaf max-length {
        when "../node-action = 'ioam:action-encapsulate'";
        type uint32;
        units bytes;
        description
          "This field specifies the maximum length of the node data list
          in octets. The max-length is only defined at the
          encapsulation node. And it's only used for the incremental
          tracing mode.";

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      }
    }

    grouping ioam-preallocated-tracing-profile {
      description
        "A grouping for incremental tracing profile.";

      leaf node-action {
        type ioam-node-action;
        description "node action";
      }

      uses encap-tracing {
        when "node-action = 'ioam:action-encapsulate'";
      }
    }

    grouping ioam-direct-export-profile {
      description
        "A grouping for direct export profile.";

      leaf node-action {
        type ioam-node-action;
        description "node action";
      }

      uses encap-tracing {
        when "node-action = 'ioam:action-encapsulate'";
      }

      leaf flow-id {
        when "../node-action = 'ioam:action-encapsulate'";
        type uint32;
        description
          "A 32-bit flow identifier. The field is set at the
           encapsulating node. The Flow ID can be uniformly assigned
           by a central controller or algorithmically generated by the
           encapsulating node. The latter approach cannot guarantee
           the uniqueness of Flow ID, yet the conflict probability is
           small due to the large Flow ID space.flow-id is used to
           correlate the exported data of the same flow from multiple
           nodes and from multiple packets.";
      }
    }

    grouping ioam-e2e-profile {
      description

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        "A grouping for edge to edge profile.";

      leaf node-action {
        type ioam-node-action;
        description
          "indicate how the node act for this profile";
      }

      container e2e-types {
        when "../node-action = 'ioam:action-encapsulate'";
        description
          "the list of e2e types for encapsulation";

        leaf use-namespace {
          type ioam-namespace;
          description
            "the namespace used for encapsulation";
        }

        leaf-list e2e-type {
          type ioam-e2e-type;
          description
            "The e2e type is only defined at the encapsulation node.";
        }
      }
    }

    grouping ioam-admin-config {
      description
        "IOAM top-level administrative configuration.";

      leaf enabled {
        type boolean;
        default false;
        description
          "When true, IOAM configuration is enabled for the system.
           Meanwhile, the IOAM data-plane functionality is enabled.";
      }
    }

   /*
    * DATA NODES
    */

    container ioam {
      description "IOAM top level container";

      container ioam-info {

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        config false;
        description
          "Describes assistant information such as units or timestamp
           format. So that monitoring systems can interpret the IOAM
           data.";

        leaf timestamp-type {
          type identityref {
            base lime:timestamp-type;
          }
          description
            "Type of timestamp, such as Truncated PTP or NTP.";
        }

        list available-interface {
          key "if-name";
          ordered-by user;
          description
            "A list of available interfaces that support IOAM.";
          leaf if-name {
            type leafref {
              path "/if:interfaces/if:interface/if:name";
            }
            description "Interface name.";
          }
        }
      }

      container ioam-profiles {
        description
          "Contains a list of IOAM profiles.";

        container admin-config {
          description
            "Contains all the administrative configurations related to
             the IOAM functionalities and all the IOAM profiles.";

          uses ioam-admin-config;
        }

        list ioam-profile {
          key "profile-name";
          ordered-by user;
          description
            "A list of IOAM profiles that configured on the node.";

          leaf profile-name {
            type string;

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            mandatory true;
            description
              "Unique identifier for each IOAM profile";
          }

          container filter {
            uses ioam-filter;
            description
              "The filter which is used to indicate the flow to apply
              IOAM.";
          }

          leaf protocol-type {
            type ioam-protocol-type;
            description
              "This item is used to indicate the carrier protocol where
              the IOAM is applied.";
          }

          container incremental-tracing-profile {
            if-feature incremental-trace;
            description
              "describe the profile for incremental tracing option";

            leaf enabled {
              type boolean;
              default false;
              description
                "When true, apply incremental tracing option to the
                 specified flow identified by the filter.";
            }

            uses ioam-incremental-tracing-profile;
          }

          container preallocated-tracing-profile {
            if-feature preallocated-trace;
            description
              "describe the profile for preallocated tracing option";

            leaf enabled {
              type boolean;
              default false;
              description
                "When true, apply preallocated tracing option to the
                 specified flow identified by the following filter.";
            }

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            uses ioam-preallocated-tracing-profile;
          }

          container direct-export-profile {
            if-feature direct-export;
            description
              "describe the profile for direct-export option";

            leaf enabled {
              type boolean;
              default false;
              description
                "When true, apply direct-export option to the
                 specified flow identified by the following filter.";
            }

            uses ioam-direct-export-profile;
          }

          container pot-profile {
            if-feature proof-of-transit;
            description
              "describe the profile for PoT option";

            leaf enabled {
              type boolean;
              default false;
              description
                "When true, apply Proof of Transit option to the
                 specified flow identified by the following filter.";
            }

            leaf pot-type {
              type ioam-pot-type;
              description
                "The type of a particular POT variant that specifies
                 the POT data that is included..";
            }
          }

          container e2e-profile {
            if-feature edge-to-edge;
            description
              "describe the profile for e2e option";

            leaf enabled {
              type boolean;
              default false;

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              description
                "When true, apply edge to edge option to the
                 specified flow identified by the following filter.";
            }

            uses ioam-e2e-profile;
          }
        }
      }
    }
  }
  <CODE ENDS>

5.  Security Considerations

   The YANG module specified in this document defines a schema for data
   that is designed to be accessed via network management protocols such
   as NETCONF [RFC6241] or RESTCONF [RFC8040].  The lowest NETCONF layer
   is the secure transport layer, and the mandatory-to-implement secure
   transport is Secure Shell (SSH) [RFC6242].  The lowest RESTCONF layer
   is HTTPS, and the mandatory-to-implement secure transport is TLS
   [RFC8446].

   The Network Configuration Access Control Model (NACM) [RFC8341]
   provides the means to restrict access for particular NETCONF or
   RESTCONF users to a preconfigured subset of all available NETCONF or
   RESTCONF protocol operations and content.

   There are a number of data nodes defined in this YANG module that are
   writable/creatable/deletable (i.e., config true, which is the
   default).  These data nodes may be considered sensitive or vulnerable
   in some network environments.  Write operations (e.g., edit-config)
   to these data nodes without proper protection can have a negative
   effect on network operations.  These are the subtrees and data nodes
   and their sensitivity/vulnerability:

   o  /ioam/ioam-profiles/admin-config

   The items in the container above include the top level administrative
   configurations related to the IOAM functionalities and all the IOAM
   profiles.  Unexpected changes to these items could lead to the IOAM
   function disruption and/ or misbehavior of all the IOAM profiles.

   o  /ioam/ioam-profiles/ioam-profile

   The entries in the list above include the whole IOAM profile
   configurations which indirectly create or modify the device

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   configurations.  Unexpected changes to these entries could lead to
   the mistake of the IOAM behavior for the corresponding flows.

6.  IANA Considerations

   RFC Ed.: In this section, replace all occurrences of 'XXXX' with the
   actual RFC number (and remove this note).

   IANA is requested to assign a new URI from the IETF XML Registry
   [RFC3688].  The following URI is suggested:

           URI: urn:ietf:params:xml:ns:yang:ietf-ioam
           Registrant Contact: The IESG.
           XML: N/A; the requested URI is an XML namespace.

   This document also requests a new YANG module name in the YANG Module
   Names registry [RFC7950] with the following suggestion:

           name: ietf-ioam
           namespace: urn:ietf:params:xml:ns:yang:ietf-ioam
           prefix: ioam
           reference: RFC XXXX

7.  Acknowledgements

   For their valuable comments, discussions, and feedback, we wish to
   acknowledge Greg Mirsky, Reshad Rahman, Tom Petch and Mickey Spiegel.

8.  References

8.1.  Normative References

   [I-D.ietf-ippm-ioam-data]
              Brockners, F., Bhandari, S., and T. Mizrahi, "Data Fields
              for In-situ OAM", draft-ietf-ippm-ioam-data-17 (work in
              progress), December 2021.

   [I-D.ietf-ippm-ioam-direct-export]
              Song, H., Gafni, B., Zhou, T., Li, Z., Brockners, F.,
              Bhandari, S., Sivakolundu, R., and T. Mizrahi, "In-situ
              OAM Direct Exporting", draft-ietf-ippm-ioam-direct-
              export-07 (work in progress), October 2021.

   [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>.

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   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/rfc6242>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

   [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>.

   [RFC8340]  Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
              BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
              <https://www.rfc-editor.org/info/rfc8340>.

   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/info/rfc8341>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

   [RFC8519]  Jethanandani, M., Agarwal, S., Huang, L., and D. Blair,
              "YANG Data Model for Network Access Control Lists (ACLs)",
              RFC 8519, DOI 10.17487/RFC8519, March 2019,
              <https://www.rfc-editor.org/info/rfc8519>.

8.2.  Informative References

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   [I-D.ietf-ippm-ioam-ipv6-options]
              Bhandari, S. and F. Brockners, "In-situ OAM IPv6 Options",
              draft-ietf-ippm-ioam-ipv6-options-06 (work in progress),
              July 2021.

   [I-D.ietf-sfc-ioam-nsh]
              Brockners, F. and S. Bhandari, "Network Service Header
              (NSH) Encapsulation for In-situ OAM (IOAM) Data", draft-
              ietf-sfc-ioam-nsh-06 (work in progress), July 2021.

Appendix A.  Examples

   This appendix is non-normative.

   tbd

Authors' Addresses

   Tianran Zhou
   Huawei
   156 Beiqing Rd.
   Beijing  100095
   China

   Email: zhoutianran@huawei.com

   Jim Guichard
   Futurewei
   United States of America

   Email: james.n.guichard@futurewei.com

   Frank Brockners
   Cisco Systems
   Hansaallee 249, 3rd Floor
   Duesseldorf, Nordrhein-Westfalen  40549
   Germany

   Email: fbrockne@cisco.com

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   Srihari Raghavan
   Cisco Systems
   Tril Infopark Sez, Ramanujan IT City
   Neville Block, 2nd floor, Old Mahabalipuram Road
   Chennai, Tamil Nadu  600113
   India

   Email: srihari@cisco.com

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