IPPM                                                        T. Zhou, Ed.
Internet-Draft                                                    Huawei
Intended status: Standards Track                             J. Guichard
Expires: 18 July 2022                                          Futurewei
                                                            F. Brockners
                                                             S. Raghavan
                                                           Cisco Systems
                                                         14 January 2022


                   A YANG Data Model for In-Situ OAM
                      draft-ietf-ippm-ioam-yang-02

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 18 July 2022.

Copyright Notice

   Copyright (c) 2022 IETF Trust and the persons identified as the
   document authors.  All rights reserved.










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   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 include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised 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 Incremental Tracing Option, Pre-allocated
   Tracing Option, Direct Export
   Option[I-D.ietf-ippm-ioam-direct-export], Proof of Transit (PoT)
   Option, and Edge-to-Edge Option.




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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:

   *  augment

   *  data model

   *  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, prove 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:

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

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

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

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

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

   *  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:

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

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

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

   *  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@2021-01-12.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 {



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

     import ietf-lime-time-types {
       prefix "lime";
       reference
         "RFC 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: <http://tools.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 2022-01-12 {
       description "Firstd revision.";
       reference "draft-ietf-ippm-ioam-yang";
     }

    /*
     * FEATURES



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     */

     feature incremental-trace
     {
       description
         "This feature indicated that the incremental tracing option is
          supported";
       reference "draft-ietf-ippm-ioam-data";
     }

     feature preallocated-trace
     {
       description
         "This feature indicated that the preallocated tracing option is
          supported";
       reference "draft-ietf-ippm-ioam-data";
     }

     feature direct-export
     {
       description
         "This feature indicated that the direct export option is
          supported";
       reference "ietf-ippm-ioam-direct-export";
     }

     feature proof-of-transit
     {
       description
         "This feature indicated that the proof of transit option is
          supported";
       reference "draft-ietf-ippm-ioam-data";
     }

     feature edge-to-edge
     {
       description
         "This feature indicated that the edge to edge option is
          supported";
       reference "draft-ietf-ippm-ioam-data";
     }

    /*
     * IDENTITIES
     */
     identity base-filter {
       description
         "Base identity to represent a filter. A filter is used to



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         specify the flow to apply the IOAM profile. ";
     }

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

     identity base-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-protocol {
       base base-protocol;
       description
         "The described IOAM data is embedded in IPv6 protocol.";
       reference "ietf-ippm-ioam-ipv6-options";
     }

     identity nsh-protocol  {
       base base-protocol;
       description
         "The described IOAM data is embedded in NSH.";
       reference "ietf-sfc-ioam-nsh";
     }

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

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

     identity base-trace-type {



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       description
         "Base identity to represent trace types";
     }

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

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

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

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

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

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

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



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

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

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

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

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

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

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

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



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         "POT data is a 16 Octet field to carry data associated to
          POT procedures.";
     }

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

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

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

     identity e2e-timestamp-seconds {
       base base-e2e-type;
       description
         "indicates presence of timestamp seconds for the
          transmission of the frame";
     }

     identity e2e-timestamp-subseconds {
       base base-e2e-type;
       description
         "indicates presence of timestamp subseconds for the
          transmission of the frame";
     }

     identity base-namespace {
       description
         "Base identity to represent the namespace";
     }

     identity namespace-ietf {
       base base-namespace;
       description
         "namespace that specified in IETF.";
     }

    /*
     * TYPE DEFINITIONS



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

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

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

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

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

     typedef ioam-e2e-type {
       type identityref {
         base base-e2e-type;
       }
       description
         "Specifies a known e2e type.";
     }



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     typedef ioam-namespace {
       type identityref {
         base 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 encapsulate";

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

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



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         }
       }

       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
         "A grouping for end to end profile.";

       leaf node-action {



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         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 encapsulate";

         leaf use-namespace {
           type ioam-namespace;
           description
             "the namespace used for the 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 {
         config false;
         description
           "Describes assistant information such as units or timestamp



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



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           }

           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.";
             }

             uses ioam-preallocated-tracing-profile;
           }




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



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             }

             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
   [RFC5246].

   The NETCONF access control model [RFC6536] 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:

   *  /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.

   *  /ioam/ioam-profiles/ioam-profile

   The entries in the list above include the whole IOAM profile
   configurations which indirectly create or modify the device
   configurations.  Unexpected changes to these entries could lead to
   the mistake of the IOAM behavior for the corresponding flows.




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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", Work in Progress, Internet-Draft, draft-
              ietf-ippm-ioam-data-17, 13 December 2021,
              <https://www.ietf.org/archive/id/draft-ietf-ippm-ioam-
              data-17.txt>.

   [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", Work in Progress, Internet-Draft,
              draft-ietf-ippm-ioam-direct-export-07, 13 October 2021,
              <https://www.ietf.org/archive/id/draft-ietf-ippm-ioam-
              direct-export-07.txt>.

   [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>.

   [RFC5246]  Dierks, T. and E. Rescorla, "The Transport Layer Security
              (TLS) Protocol Version 1.2", RFC 5246,
              DOI 10.17487/RFC5246, August 2008,
              <https://www.rfc-editor.org/info/rfc5246>.

   [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>.

   [RFC6536]  Bierman, A. and M. Bjorklund, "Network Configuration
              Protocol (NETCONF) Access Control Model", RFC 6536,
              DOI 10.17487/RFC6536, March 2012,
              <https://www.rfc-editor.org/info/rfc6536>.

   [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>.

   [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",
              Work in Progress, Internet-Draft, draft-ietf-ippm-ioam-
              ipv6-options-06, 31 July 2021,
              <https://www.ietf.org/archive/id/draft-ietf-ippm-ioam-
              ipv6-options-06.txt>.

   [I-D.ietf-sfc-ioam-nsh]
              Brockners, F. and S. Bhandari, "Network Service Header
              (NSH) Encapsulation for In-situ OAM (IOAM) Data", Work in
              Progress, Internet-Draft, draft-ietf-sfc-ioam-nsh-06, 31
              July 2021, <https://www.ietf.org/archive/id/draft-ietf-
              sfc-ioam-nsh-06.txt>.

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
   40549 Duesseldorf
   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 600113
   Tamil Nadu
   India

   Email: srihari@cisco.com










































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