



Internet Engineering Task Force (IETF)                           T. Saad
Request for Comments: 8776                              Juniper Networks
Category: Standards Track                                      R. Gandhi
ISSN: 2070-1721                                      Cisco Systems, Inc.
                                                                  X. Liu
                                                          Volta Networks
                                                               V. Beeram
                                                        Juniper Networks
                                                              I. Bryskin
                                            Futurewei Technologies, Inc.
                                                               June 2020


             Common YANG Data Types for Traffic Engineering

Abstract

   This document defines a collection of common data types and groupings
   in YANG data modeling language.  These derived common types and
   groupings are intended to be imported by modules that model Traffic
   Engineering (TE) configuration and state capabilities.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 7841.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   https://www.rfc-editor.org/info/rfc8776.

Copyright Notice

   Copyright (c) 2020 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
   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
     1.1.  Terminology
     1.2.  Prefixes in Data Node Names
   2.  Acronyms and Abbreviations
   3.  Overview
     3.1.  TE Types Module Contents
     3.2.  Packet TE Types Module Contents
   4.  TE Types YANG Module
   5.  Packet TE Types YANG Module
   6.  IANA Considerations
   7.  Security Considerations
   8.  References
     8.1.  Normative References
     8.2.  Informative References
   Acknowledgments
   Contributors
   Authors' Addresses

1.  Introduction

   YANG [RFC6020] [RFC7950] is a data modeling language used to model
   configuration data, state data, Remote Procedure Calls, and
   notifications for network management protocols such as the Network
   Configuration Protocol (NETCONF) [RFC6241].  The YANG language
   supports a small set of built-in data types and provides mechanisms
   to derive other types from the built-in types.

   This document introduces a collection of common data types derived
   from the built-in YANG data types.  The derived types and groupings
   are designed to be the common types applicable for modeling Traffic
   Engineering (TE) features in model(s) defined outside of this
   document.

1.1.  Terminology

   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.

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

1.2.  Prefixes in Data Node Names

   In this document, names of data nodes and other data model objects
   are prefixed using the standard prefix associated with the
   corresponding YANG imported modules, as shown in Table 1.

        +-----------------+----------------------+---------------+
        | Prefix          | YANG Module          | Reference     |
        +=================+======================+===============+
        | yang            | ietf-yang-types      | [RFC6991]     |
        +-----------------+----------------------+---------------+
        | inet            | ietf-inet-types      | [RFC6991]     |
        +-----------------+----------------------+---------------+
        | rt-types        | ietf-routing-types   | [RFC8294]     |
        +-----------------+----------------------+---------------+
        | te-types        | ietf-te-types        | This document |
        +-----------------+----------------------+---------------+
        | te-packet-types | ietf-te-packet-types | This document |
        +-----------------+----------------------+---------------+

             Table 1: Prefixes and Corresponding YANG Modules

2.  Acronyms and Abbreviations

   GMPLS:    Generalized Multiprotocol Label Switching

   LSP:      Label Switched Path

   LSR:      Label Switching Router

   LER:      Label Edge Router

   MPLS:     Multiprotocol Label Switching

   RSVP:     Resource Reservation Protocol

   TE:       Traffic Engineering

   DS-TE:    Differentiated Services Traffic Engineering

   SRLG:     Shared Risk Link Group

   NBMA:     Non-Broadcast Multi-Access

   APS:      Automatic Protection Switching

   SD:       Signal Degrade

   SF:       Signal Fail

   WTR:      Wait-to-Restore

   PM:       Performance Metrics

3.  Overview

   This document defines two YANG modules for common TE types:
   "ietf-te-types" for TE generic types and "ietf-te-packet-types" for
   packet-specific types.  Other technology-specific TE types are
   outside the scope of this document.

3.1.  TE Types Module Contents

   The "ietf-te-types" module (Section 4) contains common TE types that
   are independent and agnostic of any specific technology or control-
   plane instance.

   The "ietf-te-types" module contains the following YANG reusable types
   and groupings:

   te-bandwidth:
      A YANG grouping that defines the generic TE bandwidth.  The
      modeling structure allows augmentation for each technology.  For
      unspecified technologies, the string-encoded "te-bandwidth" type
      is used.

   te-label:
      A YANG grouping that defines the generic TE label.  The modeling
      structure allows augmentation for each technology.  For
      unspecified technologies, "rt-types:generalized-label" is used.

   performance-metrics-attributes:
      A YANG grouping that defines one-way and two-way measured
      Performance Metrics (PM) and indications of anomalies on link(s)
      or the path as defined in [RFC7471], [RFC8570], and [RFC7823].

   performance-metrics-throttle-container:
      A YANG grouping that defines configurable thresholds for
      advertisement suppression and measurement intervals.

   te-ds-class:
      A type representing the Differentiated Services (DS) Class-Type of
      traffic as defined in [RFC4124].

   te-label-direction:
      An enumerated type for specifying the forward or reverse direction
      of a label.

   te-hop-type:
      An enumerated type for specifying that a hop is loose or strict.

   te-global-id:
      A type representing the identifier that uniquely identifies an
      operator, which can be either a provider or a client.  The
      definition of this type is taken from [RFC6370] and [RFC5003].
      This attribute type is used solely to provide a globally unique
      context for TE topologies.

   te-node-id:
      A type representing the identifier for a node in a TE topology.
      The identifier is represented as 4 octets in dotted-quad notation.
      This attribute MAY be mapped to the Router Address TLV described
      in Section 2.4.1 of [RFC3630], the TE Router ID described in
      Section 3 of [RFC6827], the Traffic Engineering Router ID TLV
      described in Section 4.3 of [RFC5305], or the TE Router ID TLV
      described in Section 3.2.1 of [RFC6119].  The reachability of such
      a TE node MAY be achieved by a mechanism such as that described in
      Section 6.2 of [RFC6827].

   te-topology-id:
      A type representing the identifier for a topology.  It is optional
      to have one or more prefixes at the beginning, separated by
      colons.  The prefixes can be "network-types" as defined in the
      "ietf-network" module in [RFC8345], to help the user better
      understand the topology before further inquiry is made.

   te-tp-id:
      A type representing the identifier of a TE interface Link
      Termination Point (LTP) on a specific TE node where the TE link
      connects.  This attribute is mapped to a local or remote link
      identifier [RFC3630] [RFC5305].

   te-path-disjointness:
      A type representing the different resource disjointness options
      for a TE tunnel path as defined in [RFC4872].

   admin-groups:
      A union type for a TE link's classic or extended administrative
      groups as defined in [RFC3630], [RFC5305], and [RFC7308].

   srlg:
      A type representing the Shared Risk Link Group (SRLG) as defined
      in [RFC4203] and [RFC5307].

   te-metric:
      A type representing the TE metric as defined in [RFC3785].

   te-recovery-status:
      An enumerated type for the different statuses of a recovery action
      as defined in [RFC4427] and [RFC6378].

   path-attribute-flags:
      A base YANG identity for supported LSP path flags as defined in
      [RFC3209], [RFC4090], [RFC4736], [RFC5712], [RFC4920], [RFC5420],
      [RFC7570], [RFC4875], [RFC5151], [RFC5150], [RFC6001], [RFC6790],
      [RFC7260], [RFC8001], [RFC8149], and [RFC8169].

   link-protection-type:
      A base YANG identity for supported link protection types as
      defined in [RFC4872] and [RFC4427].

   restoration-scheme-type:
      A base YANG identity for supported LSP restoration schemes as
      defined in [RFC4872].

   protection-external-commands:
      A base YANG identity for supported protection-related external
      commands used for troubleshooting purposes, as defined in
      [RFC4427].

   association-type:
      A base YANG identity for supported LSP association types as
      defined in [RFC6780], [RFC4872], and [RFC4873].

   objective-function-type:
      A base YANG identity for supported path computation objective
      functions as defined in [RFC5541].

   te-tunnel-type:
      A base YANG identity for supported TE tunnel types as defined in
      [RFC3209] and [RFC4875].

   lsp-encoding-types:
      A base YANG identity for supported LSP encoding types as defined
      in [RFC3471].

   lsp-protection-type:
      A base YANG identity for supported LSP protection types as defined
      in [RFC4872] and [RFC4873].

   switching-capabilities:
      A base YANG identity for supported interface switching
      capabilities as defined in [RFC3471].

   resource-affinities-type:
      A base YANG identity for supported attribute filters associated
      with a tunnel that must be satisfied for a link to be acceptable
      as defined in [RFC2702] and [RFC3209].

   path-metric-type:
      A base YANG identity for supported path metric types as defined in
      [RFC3785] and [RFC7471].

   explicit-route-hop:
      A YANG grouping that defines supported explicit routes as defined
      in [RFC3209] and [RFC3477].

   te-link-access-type:
      An enumerated type for the different TE link access types as
      defined in [RFC3630].

3.2.  Packet TE Types Module Contents

   The "ietf-te-packet-types" module (Section 5) covers the common types
   and groupings that are specific to packet technology.

   The "ietf-te-packet-types" module contains the following YANG
   reusable types and groupings:

   backup-protection-type:
      A base YANG identity for supported protection types that a backup
      or bypass tunnel can provide as defined in [RFC4090].

   te-class-type:
      A type that represents the Diffserv-TE Class-Type as defined in
      [RFC4124].

   bc-type:
      A type that represents Diffserv-TE Bandwidth Constraints (BCs) as
      defined in [RFC4124].

   bc-model-type:
      A base YANG identity for supported Diffserv-TE Bandwidth
      Constraints Models as defined in [RFC4125], [RFC4126], and
      [RFC4127].

   te-bandwidth-requested-type:
      An enumerated type for the different options to request bandwidth
      for a specific tunnel.

   performance-metrics-attributes-packet:
      A YANG grouping that contains the generic performance metrics and
      additional packet-specific metrics.

4.  TE Types YANG Module

   The "ietf-te-types" module imports from the following modules:

   *  "ietf-yang-types" and "ietf-inet-types" as defined in [RFC6991]

   *  "ietf-routing-types" as defined in [RFC8294]

   In addition to [RFC6991] and [RFC8294], this module references the
   following documents in defining the types and YANG groupings:
   [RFC3272], [RFC4090], [RFC4202], [RFC4328], [RFC4561], [RFC4657],
   [RFC5817], [RFC6004], [RFC6511], [RFC7139], [RFC7308], [RFC7551],
   [RFC7571], [RFC7579], and [G.709].

   <CODE BEGINS> file "ietf-te-types@2020-06-10.yang"
   module ietf-te-types {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-te-types";
     prefix te-types;

     import ietf-inet-types {
       prefix inet;
       reference
         "RFC 6991: Common YANG Data Types";
     }
     import ietf-yang-types {
       prefix yang;
       reference
         "RFC 6991: Common YANG Data Types";
     }
     import ietf-routing-types {
       prefix rt-types;
       reference
         "RFC 8294: Common YANG Data Types for the Routing Area";
     }

     organization
       "IETF Traffic Engineering Architecture and Signaling (TEAS)
        Working Group";
     contact
       "WG Web:   <https://datatracker.ietf.org/wg/teas/>
        WG List:  <mailto:teas@ietf.org>

        Editor:   Tarek Saad
                  <mailto:tsaad@juniper.net>

        Editor:   Rakesh Gandhi
                  <mailto:rgandhi@cisco.com>

        Editor:   Vishnu Pavan Beeram
                  <mailto:vbeeram@juniper.net>

        Editor:   Xufeng Liu
                  <mailto:xufeng.liu.ietf@gmail.com>

        Editor:   Igor Bryskin
                  <mailto:i_bryskin@yahoo.com>";
     description
       "This YANG module contains a collection of generally useful
        YANG data type definitions specific to TE.  The model fully
        conforms to the Network Management Datastore Architecture
        (NMDA).

        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 (RFC 2119) (RFC 8174) when, and only when,
        they appear in all capitals, as shown here.

        Copyright (c) 2020 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
        (https://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC 8776; see the
        RFC itself for full legal notices.";

     revision 2020-06-10 {
       description
         "Latest revision of TE types.";
       reference
         "RFC 8776: Common YANG Data Types for Traffic Engineering";
     }

     /**
      * Typedefs
      */

     typedef admin-group {
       type yang:hex-string {
         /* 01:02:03:04 */
         length "1..11";
       }
       description
         "Administrative group / resource class / color representation
          in 'hex-string' type.
          The most significant byte in the hex-string is the farthest
          to the left in the byte sequence.  Leading zero bytes in the
          configured value may be omitted for brevity.";
       reference
         "RFC 3630: Traffic Engineering (TE) Extensions to OSPF
          Version 2
          RFC 5305: IS-IS Extensions for Traffic Engineering
          RFC 7308: Extended Administrative Groups in MPLS Traffic
          Engineering (MPLS-TE)";
     }

     typedef admin-groups {
       type union {
         type admin-group;
         type extended-admin-group;
       }
       description
         "Derived types for TE administrative groups.";
     }

     typedef extended-admin-group {
       type yang:hex-string;
       description
         "Extended administrative group / resource class / color
          representation in 'hex-string' type.
          The most significant byte in the hex-string is the farthest
          to the left in the byte sequence.  Leading zero bytes in the
          configured value may be omitted for brevity.";
       reference
         "RFC 7308: Extended Administrative Groups in MPLS Traffic
          Engineering (MPLS-TE)";
     }

     typedef path-attribute-flags {
       type union {
         type identityref {
           base session-attributes-flags;
         }
         type identityref {
           base lsp-attributes-flags;
         }
       }
       description
         "Path attributes flags type.";
     }

     typedef performance-metrics-normality {
       type enumeration {
         enum unknown {
           value 0;
           description
             "Unknown.";
         }
         enum normal {
           value 1;
           description
             "Normal.  Indicates that the anomalous bit is not set.";
         }
         enum abnormal {
           value 2;
           description
             "Abnormal.  Indicates that the anomalous bit is set.";
         }
       }
       description
         "Indicates whether a performance metric is normal (anomalous
          bit not set), abnormal (anomalous bit set), or unknown.";
       reference
         "RFC 7471: OSPF Traffic Engineering (TE) Metric Extensions
          RFC 7823: Performance-Based Path Selection for Explicitly
          Routed Label Switched Paths (LSPs) Using TE Metric
          Extensions
          RFC 8570: IS-IS Traffic Engineering (TE) Metric Extensions";
     }

     typedef srlg {
       type uint32;
       description
         "SRLG type.";
       reference
         "RFC 4203: OSPF Extensions in Support of Generalized
          Multi-Protocol Label Switching (GMPLS)
          RFC 5307: IS-IS Extensions in Support of Generalized
          Multi-Protocol Label Switching (GMPLS)";
     }

     typedef te-common-status {
       type enumeration {
         enum up {
           description
             "Enabled.";
         }
         enum down {
           description
             "Disabled.";
         }
         enum testing {
           description
             "In some test mode.";
         }
         enum preparing-maintenance {
           description
             "The resource is disabled in the control plane to prepare
              for a graceful shutdown for maintenance purposes.";
           reference
             "RFC 5817: Graceful Shutdown in MPLS and Generalized MPLS
              Traffic Engineering Networks";
         }
         enum maintenance {
           description
             "The resource is disabled in the data plane for maintenance
              purposes.";
         }
         enum unknown {
           description
             "Status is unknown.";
         }
       }
       description
         "Defines a type representing the common states of a TE
          resource.";
     }

     typedef te-bandwidth {
       type string {
         pattern '0[xX](0((\.0?)?[pP](\+)?0?|(\.0?))|'
               + '1(\.([\da-fA-F]{0,5}[02468aAcCeE]?)?)?'
               + '[pP](\+)?(12[0-7]|'
               + '1[01]\d|0?\d?\d)?)|0[xX][\da-fA-F]{1,8}|\d+'
               + '(,(0[xX](0((\.0?)?[pP](\+)?0?|(\.0?))|'
               + '1(\.([\da-fA-F]{0,5}[02468aAcCeE]?)?)?'
               + '[pP](\+)?(12[0-7]|'
               + '1[01]\d|0?\d?\d)?)|0[xX][\da-fA-F]{1,8}|\d+))*';
       }
       description
         "This is the generic bandwidth type.  It is a string containing
          a list of numbers separated by commas, where each of these
          numbers can be non-negative decimal, hex integer, or
          hex float:

          (dec | hex | float)[*(','(dec | hex | float))]

          For the packet-switching type, the string encoding follows
          the type 'bandwidth-ieee-float32' as defined in RFC 8294
          (e.g., 0x1p10), where the units are in bytes per second.

          For the Optical Transport Network (OTN) switching type,
          a list of integers can be used, such as '0,2,3,1', indicating
          two ODU0s and one ODU3.  ('ODU' stands for 'Optical Data
          Unit'.)  For Dense Wavelength Division Multiplexing (DWDM),
          a list of pairs of slot numbers and widths can be used,
          such as '0,2,3,3', indicating a frequency slot 0 with
          slot width 2 and a frequency slot 3 with slot width 3.
          Canonically, the string is represented as all lowercase and in
          hex, where the prefix '0x' precedes the hex number.";
       reference
         "RFC 8294: Common YANG Data Types for the Routing Area
          ITU-T Recommendation G.709: Interfaces for the
          optical transport network";
     }

     typedef te-ds-class {
       type uint8 {
         range "0..7";
       }
       description
         "The Differentiated Services Class-Type of traffic.";
       reference
         "RFC 4124: Protocol Extensions for Support of Diffserv-aware
          MPLS Traffic Engineering, Section 4.3.1";
     }

     typedef te-global-id {
       type uint32;
       description
         "An identifier to uniquely identify an operator, which can be
          either a provider or a client.
          The definition of this type is taken from RFCs 6370 and 5003.
          This attribute type is used solely to provide a globally
          unique context for TE topologies.";
       reference
         "RFC 5003: Attachment Individual Identifier (AII) Types for
          Aggregation
          RFC 6370: MPLS Transport Profile (MPLS-TP) Identifiers";
     }

     typedef te-hop-type {
       type enumeration {
         enum loose {
           description
             "A loose hop in an explicit path.";
         }
         enum strict {
           description
             "A strict hop in an explicit path.";
         }
       }
       description
         "Enumerated type for specifying loose or strict paths.";
       reference
         "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels,
          Section 4.3.3";
     }

     typedef te-link-access-type {
       type enumeration {
         enum point-to-point {
           description
             "The link is point-to-point.";
         }
         enum multi-access {
           description
             "The link is multi-access, including broadcast and NBMA.";
         }
       }
       description
         "Defines a type representing the access type of a TE link.";
       reference
         "RFC 3630: Traffic Engineering (TE) Extensions to OSPF
          Version 2";
     }

     typedef te-label-direction {
       type enumeration {
         enum forward {
           description
             "Label allocated for the forward LSP direction.";
         }
         enum reverse {
           description
             "Label allocated for the reverse LSP direction.";
         }
       }
       description
         "Enumerated type for specifying the forward or reverse
          label.";
     }

     typedef te-link-direction {
       type enumeration {
         enum incoming {
           description
             "The explicit route represents an incoming link on
              a node.";
         }
         enum outgoing {
           description
             "The explicit route represents an outgoing link on
              a node.";
         }
       }
       description
         "Enumerated type for specifying the direction of a link on
          a node.";
     }

     typedef te-metric {
       type uint32;
       description
         "TE metric.";
       reference
         "RFC 3785: Use of Interior Gateway Protocol (IGP) Metric as a
          second MPLS Traffic Engineering (TE) Metric";
     }

     typedef te-node-id {
       type yang:dotted-quad;
       description
         "A type representing the identifier for a node in a TE
          topology.
          The identifier is represented as 4 octets in dotted-quad
          notation.
          This attribute MAY be mapped to the Router Address TLV
          described in Section 2.4.1 of RFC 3630, the TE Router ID
          described in Section 3 of RFC 6827, the Traffic Engineering
          Router ID TLV described in Section 4.3 of RFC 5305, or the
          TE Router ID TLV described in Section 3.2.1 of RFC 6119.
          The reachability of such a TE node MAY be achieved by a
          mechanism such as that described in Section 6.2 of RFC 6827.";
       reference
         "RFC 3630: Traffic Engineering (TE) Extensions to OSPF
          Version 2, Section 2.4.1
          RFC 5305: IS-IS Extensions for Traffic Engineering,
          Section 4.3
          RFC 6119: IPv6 Traffic Engineering in IS-IS, Section 3.2.1
          RFC 6827: Automatically Switched Optical Network (ASON)
          Routing for OSPFv2 Protocols, Section 3";
     }

     typedef te-oper-status {
       type te-common-status;
       description
         "Defines a type representing the operational status of
          a TE resource.";
     }

     typedef te-admin-status {
       type te-common-status;
       description
         "Defines a type representing the administrative status of
          a TE resource.";
     }

     typedef te-path-disjointness {
       type bits {
         bit node {
           position 0;
           description
             "Node disjoint.";
         }
         bit link {
           position 1;
           description
             "Link disjoint.";
         }
         bit srlg {
           position 2;
           description
             "SRLG (Shared Risk Link Group) disjoint.";
         }
       }
       description
         "Type of the resource disjointness for a TE tunnel path.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     typedef te-recovery-status {
       type enumeration {
         enum normal {
           description
             "Both the recovery span and the working span are fully
              allocated and active, data traffic is being
              transported over (or selected from) the working
              span, and no trigger events are reported.";
         }
         enum recovery-started {
           description
             "The recovery action has been started but not completed.";
         }
         enum recovery-succeeded {
           description
             "The recovery action has succeeded.  The working span has
              reported a failure/degrade condition, and the user traffic
              is being transported (or selected) on the recovery span.";
         }
         enum recovery-failed {
           description
             "The recovery action has failed.";
         }
         enum reversion-started {
           description
             "The reversion has started.";
         }
         enum reversion-succeeded {
           description
             "The reversion action has succeeded.";
         }
         enum reversion-failed {
           description
             "The reversion has failed.";
         }
         enum recovery-unavailable {
           description
             "The recovery is unavailable, as a result of either an
              operator's lockout command or a failure condition
              detected on the recovery span.";
         }
         enum recovery-admin {
           description
             "The operator has issued a command to switch the user
              traffic to the recovery span.";
         }
         enum wait-to-restore {
           description
             "The recovery domain is recovering from a failure/degrade
              condition on the working span that is being controlled by
              the Wait-to-Restore (WTR) timer.";
         }
       }
       description
         "Defines the status of a recovery action.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)
          RFC 6378: MPLS Transport Profile (MPLS-TP) Linear Protection";
     }

     typedef te-template-name {
       type string {
         pattern '/?([a-zA-Z0-9\-_.]+)(/[a-zA-Z0-9\-_.]+)*';
       }
       description
         "A type for the name of a TE node template or TE link
          template.";
     }

     typedef te-topology-event-type {
       type enumeration {
         enum add {
           value 0;
           description
             "A TE node or TE link has been added.";
         }
         enum remove {
           value 1;
           description
             "A TE node or TE link has been removed.";
         }
         enum update {
           value 2;
           description
             "A TE node or TE link has been updated.";
         }
       }
       description
         "TE event type for notifications.";
     }

     typedef te-topology-id {
       type union {
         type string {
           length "0";
           // empty string
         }
         type string {
           pattern '([a-zA-Z0-9\-_.]+:)*'
                 + '/?([a-zA-Z0-9\-_.]+)(/[a-zA-Z0-9\-_.]+)*';
         }
       }
       description
         "An identifier for a topology.
          It is optional to have one or more prefixes at the beginning,
          separated by colons.  The prefixes can be 'network-types' as
          defined in the 'ietf-network' module in RFC 8345, to help the
          user better understand the topology before further inquiry
          is made.";
       reference
         "RFC 8345: A YANG Data Model for Network Topologies";
     }

     typedef te-tp-id {
       type union {
         type uint32;
         // Unnumbered
         type inet:ip-address;
         // IPv4 or IPv6 address
       }
       description
         "An identifier for a TE link endpoint on a node.
          This attribute is mapped to a local or remote link identifier
          as defined in RFCs 3630 and 5305.";
       reference
         "RFC 3630: Traffic Engineering (TE) Extensions to OSPF
          Version 2
          RFC 5305: IS-IS Extensions for Traffic Engineering";
     }

     /* TE features */

     feature p2mp-te {
       description
         "Indicates support for Point-to-Multipoint TE (P2MP-TE).";
       reference
         "RFC 4875: Extensions to Resource Reservation Protocol -
          Traffic Engineering (RSVP-TE) for Point-to-Multipoint TE
          Label Switched Paths (LSPs)";
     }

     feature frr-te {
       description
         "Indicates support for TE Fast Reroute (FRR).";
       reference
         "RFC 4090: Fast Reroute Extensions to RSVP-TE for LSP Tunnels";
     }

     feature extended-admin-groups {
       description
         "Indicates support for TE link extended administrative
          groups.";
       reference
         "RFC 7308: Extended Administrative Groups in MPLS Traffic
          Engineering (MPLS-TE)";
     }

     feature named-path-affinities {
       description
         "Indicates support for named path affinities.";
     }

     feature named-extended-admin-groups {
       description
         "Indicates support for named extended administrative groups.";
     }

     feature named-srlg-groups {
       description
         "Indicates support for named SRLG groups.";
     }

     feature named-path-constraints {
       description
         "Indicates support for named path constraints.";
     }

     feature path-optimization-metric {
       description
         "Indicates support for path optimization metrics.";
     }

     feature path-optimization-objective-function {
       description
         "Indicates support for path optimization objective functions.";
     }

     /*
      * Identities
      */

     identity session-attributes-flags {
       description
         "Base identity for the RSVP-TE session attributes flags.";
     }

     identity local-protection-desired {
       base session-attributes-flags;
       description
         "Local protection is desired.";
       reference
         "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels,
          Section 4.7.1";
     }

     identity se-style-desired {
       base session-attributes-flags;
       description
         "Shared explicit style, to allow the LSP to be established
          and share resources with the old LSP.";
       reference
         "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels";
     }

     identity local-recording-desired {
       base session-attributes-flags;
       description
         "Label recording is desired.";
       reference
         "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels,
          Section 4.7.1";
     }

     identity bandwidth-protection-desired {
       base session-attributes-flags;
       description
         "Requests FRR bandwidth protection on LSRs, if present.";
       reference
         "RFC 4090: Fast Reroute Extensions to RSVP-TE for LSP Tunnels";
     }

     identity node-protection-desired {
       base session-attributes-flags;
       description
         "Requests FRR node protection on LSRs, if present.";
       reference
         "RFC 4090: Fast Reroute Extensions to RSVP-TE for LSP Tunnels";
     }

     identity path-reevaluation-request {
       base session-attributes-flags;
       description
         "This flag indicates that a path re-evaluation (of the
          current path in use) is requested.  Note that this does
          not trigger any LSP reroutes but instead just signals a
          request to evaluate whether a preferable path exists.";
       reference
         "RFC 4736: Reoptimization of Multiprotocol Label Switching
          (MPLS) Traffic Engineering (TE) Loosely Routed Label Switched
          Path (LSP)";
     }

     identity soft-preemption-desired {
       base session-attributes-flags;
       description
         "Soft preemption of LSP resources is desired.";
       reference
         "RFC 5712: MPLS Traffic Engineering Soft Preemption";
     }

     identity lsp-attributes-flags {
       description
         "Base identity for LSP attributes flags.";
     }

     identity end-to-end-rerouting-desired {
       base lsp-attributes-flags;
       description
         "Indicates end-to-end rerouting behavior for an LSP
          undergoing establishment.  This MAY also be used to
          specify the behavior of end-to-end LSP recovery for
          established LSPs.";
       reference
         "RFC 4920: Crankback Signaling Extensions for MPLS and GMPLS
          RSVP-TE
          RFC 5420: Encoding of Attributes for MPLS LSP Establishment
          Using Resource Reservation Protocol Traffic Engineering
          (RSVP-TE)
          RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)";
     }

     identity boundary-rerouting-desired {
       base lsp-attributes-flags;
       description
         "Indicates boundary rerouting behavior for an LSP undergoing
          establishment.  This MAY also be used to specify
          segment-based LSP recovery through nested crankback for
          established LSPs.  The boundary Area Border Router (ABR) /
          Autonomous System Border Router (ASBR) can decide to forward
          the PathErr message upstream to either an upstream boundary
          ABR/ASBR or the ingress LSR.  Alternatively, it can try to
          select another egress boundary LSR.";
       reference
         "RFC 4920: Crankback Signaling Extensions for MPLS and GMPLS
          RSVP-TE
          RFC 5420: Encoding of Attributes for MPLS LSP Establishment
          Using Resource Reservation Protocol Traffic Engineering
          (RSVP-TE)
          RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)";
     }

     identity segment-based-rerouting-desired {
       base lsp-attributes-flags;
       description
         "Indicates segment-based rerouting behavior for an LSP
          undergoing establishment.  This MAY also be used to specify
          segment-based LSP recovery for established LSPs.";
       reference
         "RFC 4920: Crankback Signaling Extensions for MPLS and GMPLS
          RSVP-TE
          RFC 5420: Encoding of Attributes for MPLS LSP Establishment
          Using Resource Reservation Protocol Traffic Engineering
          (RSVP-TE)
          RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)";
     }

     identity lsp-integrity-required {
       base lsp-attributes-flags;
       description
         "Indicates that LSP integrity is required.";
       reference
         "RFC 4875: Extensions to Resource Reservation Protocol -
          Traffic Engineering (RSVP-TE) for Point-to-Multipoint TE
          Label Switched Paths (LSPs)
          RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)";
     }

     identity contiguous-lsp-desired {
       base lsp-attributes-flags;
       description
         "Indicates that a contiguous LSP is desired.";
       reference
         "RFC 5151: Inter-Domain MPLS and GMPLS Traffic Engineering --
          Resource Reservation Protocol-Traffic Engineering (RSVP-TE)
          Extensions
          RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)";
     }

     identity lsp-stitching-desired {
       base lsp-attributes-flags;
       description
         "Indicates that LSP stitching is desired.";
       reference
         "RFC 5150: Label Switched Path Stitching with Generalized
          Multiprotocol Label Switching Traffic Engineering (GMPLS TE)
          RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)";
     }

     identity pre-planned-lsp-flag {
       base lsp-attributes-flags;
       description
         "Indicates that the LSP MUST be provisioned in the
          control plane only.";
       reference
         "RFC 6001: Generalized MPLS (GMPLS) Protocol Extensions for
          Multi-Layer and Multi-Region Networks (MLN/MRN)
          RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)";
     }

     identity non-php-behavior-flag {
       base lsp-attributes-flags;
       description
         "Indicates that non-PHP (non-Penultimate Hop Popping) behavior
          for the LSP is desired.";
       reference
         "RFC 6511: Non-Penultimate Hop Popping Behavior and Out-of-Band
          Mapping for RSVP-TE Label Switched Paths
          RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)";
     }

     identity oob-mapping-flag {
       base lsp-attributes-flags;
       description
         "Indicates that signaling of the egress binding information is
          out of band (e.g., via the Border Gateway Protocol (BGP)).";
       reference
         "RFC 6511: Non-Penultimate Hop Popping Behavior and Out-of-Band
          Mapping for RSVP-TE Label Switched Paths
          RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)";
     }

     identity entropy-label-capability {
       base lsp-attributes-flags;
       description
         "Indicates entropy label capability.";
       reference
         "RFC 6790: The Use of Entropy Labels in MPLS Forwarding
          RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)";
     }

     identity oam-mep-entity-desired {
       base lsp-attributes-flags;
       description
         "OAM Maintenance Entity Group End Point (MEP) entities
          desired.";
       reference
         "RFC 7260: GMPLS RSVP-TE Extensions for Operations,
          Administration, and Maintenance (OAM) Configuration";
     }

     identity oam-mip-entity-desired {
       base lsp-attributes-flags;
       description
         "OAM Maintenance Entity Group Intermediate Points (MIP)
          entities desired.";
       reference
         "RFC 7260: GMPLS RSVP-TE Extensions for Operations,
          Administration, and Maintenance (OAM) Configuration";
     }

     identity srlg-collection-desired {
       base lsp-attributes-flags;
       description
         "SRLG collection desired.";
       reference
         "RFC 7570: Label Switched Path (LSP) Attribute in the Explicit
          Route Object (ERO)
          RFC 8001: RSVP-TE Extensions for Collecting Shared Risk
          Link Group (SRLG) Information";
     }

     identity loopback-desired {
       base lsp-attributes-flags;
       description
         "This flag indicates that a particular node on the LSP is
          required to enter loopback mode.  This can also be
          used to specify the loopback state of the node.";
       reference
         "RFC 7571: GMPLS RSVP-TE Extensions for Lock Instruct and
          Loopback";
     }

     identity p2mp-te-tree-eval-request {
       base lsp-attributes-flags;
       description
         "P2MP-TE tree re-evaluation request.";
       reference
         "RFC 8149: RSVP Extensions for Reoptimization of Loosely Routed
          Point-to-Multipoint Traffic Engineering Label Switched Paths
          (LSPs)";
     }

     identity rtm-set-desired {
       base lsp-attributes-flags;
       description
         "Residence Time Measurement (RTM) attribute flag requested.";
       reference
         "RFC 8169: Residence Time Measurement in MPLS Networks";
     }

     identity link-protection-type {
       description
         "Base identity for the link protection type.";
     }

     identity link-protection-unprotected {
       base link-protection-type;
       description
         "Unprotected link type.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity link-protection-extra-traffic {
       base link-protection-type;
       description
         "Extra-Traffic protected link type.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity link-protection-shared {
       base link-protection-type;
       description
         "Shared protected link type.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity link-protection-1-for-1 {
       base link-protection-type;
       description
         "One-for-one (1:1) protected link type.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity link-protection-1-plus-1 {
       base link-protection-type;
       description
         "One-plus-one (1+1) protected link type.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity link-protection-enhanced {
       base link-protection-type;
       description
         "A compound link protection type derived from the underlay
          TE tunnel protection configuration supporting the TE link.";
     }

     identity association-type {
       description
         "Base identity for the tunnel association.";
     }

     identity association-type-recovery {
       base association-type;
       description
         "Association type for recovery, used to associate LSPs of the
          same tunnel for recovery.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery
          RFC 6780: RSVP ASSOCIATION Object Extensions";
     }

     identity association-type-resource-sharing {
       base association-type;
       description
         "Association type for resource sharing, used to enable
          resource sharing during make-before-break.";
       reference
         "RFC 4873: GMPLS Segment Recovery
          RFC 6780: RSVP ASSOCIATION Object Extensions";
     }

     identity association-type-double-sided-bidir {
       base association-type;
       description
         "Association type for double-sided bidirectional LSPs,
          used to associate two LSPs of two tunnels that are
          independently configured on either endpoint.";
       reference
         "RFC 7551: RSVP-TE Extensions for Associated Bidirectional
          Label Switched Paths (LSPs)";
     }

     identity association-type-single-sided-bidir {
       base association-type;
       description
         "Association type for single-sided bidirectional LSPs,
          used to associate two LSPs of two tunnels, where one
          tunnel is configured on one side/endpoint and the other
          tunnel is dynamically created on the other endpoint.";
       reference
         "RFC 6780: RSVP ASSOCIATION Object Extensions
          RFC 7551: RSVP-TE Extensions for Associated Bidirectional
          Label Switched Paths (LSPs)";
     }

     identity objective-function-type {
       description
         "Base objective function type.";
     }

     identity of-minimize-cost-path {
       base objective-function-type;
       description
         "Objective function for minimizing path cost.";
       reference
         "RFC 5541: Encoding of Objective Functions in the Path
          Computation Element Communication Protocol (PCEP)";
     }

     identity of-minimize-load-path {
       base objective-function-type;
       description
         "Objective function for minimizing the load on one or more
          paths.";
       reference
         "RFC 5541: Encoding of Objective Functions in the Path
          Computation Element Communication Protocol (PCEP)";
     }

     identity of-maximize-residual-bandwidth {
       base objective-function-type;
       description
         "Objective function for maximizing residual bandwidth.";
       reference
         "RFC 5541: Encoding of Objective Functions in the Path
          Computation Element Communication Protocol (PCEP)";
     }

     identity of-minimize-agg-bandwidth-consumption {
       base objective-function-type;
       description
         "Objective function for minimizing aggregate bandwidth
          consumption.";
       reference
         "RFC 5541: Encoding of Objective Functions in the Path
          Computation Element Communication Protocol (PCEP)";
     }

     identity of-minimize-load-most-loaded-link {
       base objective-function-type;
       description
         "Objective function for minimizing the load on the link that
          is carrying the highest load.";
       reference
         "RFC 5541: Encoding of Objective Functions in the Path
          Computation Element Communication Protocol (PCEP)";
     }

     identity of-minimize-cost-path-set {
       base objective-function-type;
       description
         "Objective function for minimizing the cost on a path set.";
       reference
         "RFC 5541: Encoding of Objective Functions in the Path
          Computation Element Communication Protocol (PCEP)";
     }

     identity path-computation-method {
       description
         "Base identity for supported path computation mechanisms.";
     }

     identity path-locally-computed {
       base path-computation-method;
       description
         "Indicates a constrained-path LSP in which the
          path is computed by the local LER.";
       reference
         "RFC 3272: Overview and Principles of Internet Traffic
          Engineering, Section 5.4";
     }

     identity path-externally-queried {
       base path-computation-method;
       description
         "Constrained-path LSP in which the path is obtained by
          querying an external source, such as a PCE server.
          In the case that an LSP is defined to be externally queried,
          it may also have associated explicit definitions (provided
          to the external source to aid computation).  The path that is
          returned by the external source may require further local
          computation on the device.";
       reference
         "RFC 3272: Overview and Principles of Internet Traffic
          Engineering
          RFC 4657: Path Computation Element (PCE) Communication
          Protocol Generic Requirements";
     }

     identity path-explicitly-defined {
       base path-computation-method;
       description
         "Constrained-path LSP in which the path is
          explicitly specified as a collection of strict and/or loose
          hops.";
       reference
         "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels
          RFC 3272: Overview and Principles of Internet Traffic
          Engineering";
     }

     identity lsp-metric-type {
       description
         "Base identity for the LSP metric specification types.";
     }

     identity lsp-metric-relative {
       base lsp-metric-type;
       description
         "The metric specified for the LSPs to which this identity
          refers is specified as a value relative to the IGP metric
          cost to the LSP's tail end.";
       reference
         "RFC 4657: Path Computation Element (PCE) Communication
          Protocol Generic Requirements";
     }

     identity lsp-metric-absolute {
       base lsp-metric-type;
       description
         "The metric specified for the LSPs to which this identity
          refers is specified as an absolute value.";
       reference
         "RFC 4657: Path Computation Element (PCE) Communication
          Protocol Generic Requirements";
     }

     identity lsp-metric-inherited {
       base lsp-metric-type;
       description
         "The metric for the LSPs to which this identity refers is
          not specified explicitly; rather, it is directly inherited
          from the IGP cost.";
       reference
         "RFC 4657: Path Computation Element (PCE) Communication
          Protocol Generic Requirements";
     }

     identity te-tunnel-type {
       description
         "Base identity from which specific tunnel types are derived.";
     }

     identity te-tunnel-p2p {
       base te-tunnel-type;
       description
         "TE Point-to-Point (P2P) tunnel type.";
       reference
         "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels";
     }

     identity te-tunnel-p2mp {
       base te-tunnel-type;
       description
         "TE P2MP tunnel type.";
       reference
         "RFC 4875: Extensions to Resource Reservation Protocol -
          Traffic Engineering (RSVP-TE) for Point-to-Multipoint TE
          Label Switched Paths (LSPs)";
     }

     identity tunnel-action-type {
       description
         "Base identity from which specific tunnel action types
          are derived.";
     }

     identity tunnel-action-resetup {
       base tunnel-action-type;
       description
         "TE tunnel action that tears down the tunnel's current LSP
          (if any) and attempts to re-establish a new LSP.";
     }

     identity tunnel-action-reoptimize {
       base tunnel-action-type;
       description
         "TE tunnel action that reoptimizes the placement of the
          tunnel LSP(s).";
     }

     identity tunnel-action-switchpath {
       base tunnel-action-type;
       description
         "TE tunnel action that switches the tunnel's LSP to use the
          specified path.";
     }

     identity te-action-result {
       description
         "Base identity from which specific TE action results
          are derived.";
     }

     identity te-action-success {
       base te-action-result;
       description
         "TE action was successful.";
     }

     identity te-action-fail {
       base te-action-result;
       description
         "TE action failed.";
     }

     identity tunnel-action-inprogress {
       base te-action-result;
       description
         "TE action is in progress.";
     }

     identity tunnel-admin-state-type {
       description
         "Base identity for TE tunnel administrative states.";
     }

     identity tunnel-admin-state-up {
       base tunnel-admin-state-type;
       description
         "Tunnel's administrative state is up.";
     }

     identity tunnel-admin-state-down {
       base tunnel-admin-state-type;
       description
         "Tunnel's administrative state is down.";
     }

     identity tunnel-state-type {
       description
         "Base identity for TE tunnel states.";
     }

     identity tunnel-state-up {
       base tunnel-state-type;
       description
         "Tunnel's state is up.";
     }

     identity tunnel-state-down {
       base tunnel-state-type;
       description
         "Tunnel's state is down.";
     }

     identity lsp-state-type {
       description
         "Base identity for TE LSP states.";
     }

     identity lsp-path-computing {
       base lsp-state-type;
       description
         "State path computation is in progress.";
     }

     identity lsp-path-computation-ok {
       base lsp-state-type;
       description
         "State path computation was successful.";
     }

     identity lsp-path-computation-failed {
       base lsp-state-type;
       description
         "State path computation failed.";
     }

     identity lsp-state-setting-up {
       base lsp-state-type;
       description
         "State is being set up.";
     }

     identity lsp-state-setup-ok {
       base lsp-state-type;
       description
         "State setup was successful.";
     }

     identity lsp-state-setup-failed {
       base lsp-state-type;
       description
         "State setup failed.";
     }

     identity lsp-state-up {
       base lsp-state-type;
       description
         "State is up.";
     }

     identity lsp-state-tearing-down {
       base lsp-state-type;
       description
         "State is being torn down.";
     }

     identity lsp-state-down {
       base lsp-state-type;
       description
         "State is down.";
     }

     identity path-invalidation-action-type {
       description
         "Base identity for TE path invalidation action types.";
     }

     identity path-invalidation-action-drop {
       base path-invalidation-action-type;
       description
         "Upon invalidation of the TE tunnel path, the tunnel remains
          valid, but any packet mapped over the tunnel is dropped.";
       reference
         "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels,
          Section 2.5";
     }

     identity path-invalidation-action-teardown {
       base path-invalidation-action-type;
       description
         "TE path invalidation action teardown.";
       reference
         "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels,
          Section 2.5";
     }

     identity lsp-restoration-type {
       description
         "Base identity from which LSP restoration types are derived.";
     }

     identity lsp-restoration-restore-any {
       base lsp-restoration-type;
       description
         "Any LSP affected by a failure is restored.";
     }

     identity lsp-restoration-restore-all {
       base lsp-restoration-type;
       description
         "Affected LSPs are restored after all LSPs of the tunnel are
          broken.";
     }

     identity restoration-scheme-type {
       description
         "Base identity for LSP restoration schemes.";
     }

     identity restoration-scheme-preconfigured {
       base restoration-scheme-type;
       description
         "Restoration LSP is preconfigured prior to the failure.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity restoration-scheme-precomputed {
       base restoration-scheme-type;
       description
         "Restoration LSP is precomputed prior to the failure.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity restoration-scheme-presignaled {
       base restoration-scheme-type;
       description
         "Restoration LSP is presignaled prior to the failure.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity lsp-protection-type {
       description
         "Base identity from which LSP protection types are derived.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity lsp-protection-unprotected {
       base lsp-protection-type;
       description
         "'Unprotected' LSP protection type.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity lsp-protection-reroute-extra {
       base lsp-protection-type;
       description
         "'(Full) Rerouting' LSP protection type.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity lsp-protection-reroute {
       base lsp-protection-type;
       description
         "'Rerouting without Extra-Traffic' LSP protection type.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity lsp-protection-1-for-n {
       base lsp-protection-type;
       description
         "'1:N Protection with Extra-Traffic' LSP protection type.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity lsp-protection-1-for-1 {
       base lsp-protection-type;
       description
         "LSP protection '1:1 Protection Type'.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity lsp-protection-unidir-1-plus-1 {
       base lsp-protection-type;
       description
         "'1+1 Unidirectional Protection' LSP protection type.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity lsp-protection-bidir-1-plus-1 {
       base lsp-protection-type;
       description
         "'1+1 Bidirectional Protection' LSP protection type.";
       reference
         "RFC 4872: RSVP-TE Extensions in Support of End-to-End
          Generalized Multi-Protocol Label Switching (GMPLS) Recovery";
     }

     identity lsp-protection-extra-traffic {
       base lsp-protection-type;
       description
         "Extra-Traffic LSP protection type.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity lsp-protection-state {
       description
         "Base identity of protection states for reporting purposes.";
     }

     identity normal {
       base lsp-protection-state;
       description
         "Normal state.";
     }

     identity signal-fail-of-protection {
       base lsp-protection-state;
       description
         "The protection transport entity has a signal fail condition
          that is of higher priority than the forced switchover
          command.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity lockout-of-protection {
       base lsp-protection-state;
       description
         "A Loss of Protection (LoP) command is active.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity forced-switch {
       base lsp-protection-state;
       description
         "A forced switchover command is active.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity signal-fail {
       base lsp-protection-state;
       description
         "There is a signal fail condition on either the working path
          or the protection path.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity signal-degrade {
       base lsp-protection-state;
       description
         "There is a signal degrade condition on either the working
          path or the protection path.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity manual-switch {
       base lsp-protection-state;
       description
         "A manual switchover command is active.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity wait-to-restore {
       base lsp-protection-state;
       description
         "A WTR timer is running.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity do-not-revert {
       base lsp-protection-state;
       description
         "A Do Not Revert (DNR) condition is active because of
          non-revertive behavior.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity failure-of-protocol {
       base lsp-protection-state;
       description
         "LSP protection is not working because of a protocol failure
          condition.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity protection-external-commands {
       description
         "Base identity from which protection-related external commands
          used for troubleshooting purposes are derived.";
     }

     identity action-freeze {
       base protection-external-commands;
       description
         "A temporary configuration action initiated by an operator
          command that prevents any switchover action from being taken
          and, as such, freezes the current state.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity clear-freeze {
       base protection-external-commands;
       description
         "An action that clears the active freeze state.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity action-lockout-of-normal {
       base protection-external-commands;
       description
         "A temporary configuration action initiated by an operator
          command to ensure that the normal traffic is not allowed
          to use the protection transport entity.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity clear-lockout-of-normal {
       base protection-external-commands;
       description
         "An action that clears the active lockout of the
          normal state.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity action-lockout-of-protection {
       base protection-external-commands;
       description
         "A temporary configuration action initiated by an operator
          command to ensure that the protection transport entity is
          temporarily not available to transport a traffic signal
          (either normal or Extra-Traffic).";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity action-forced-switch {
       base protection-external-commands;
       description
         "A switchover action initiated by an operator command to switch
          the Extra-Traffic signal, the normal traffic signal, or the
          null signal to the protection transport entity, unless a
          switchover command of equal or higher priority is in effect.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity action-manual-switch {
       base protection-external-commands;
       description
         "A switchover action initiated by an operator command to switch
          the Extra-Traffic signal, the normal traffic signal, or
          the null signal to the protection transport entity, unless
          a fault condition exists on other transport entities or a
          switchover command of equal or higher priority is in effect.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity action-exercise {
       base protection-external-commands;
       description
         "An action that starts testing whether or not APS communication
          is operating correctly.  It is of lower priority than any
          other state or command.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity clear {
       base protection-external-commands;
       description
         "An action that clears the active near-end lockout of a
          protection, forced switchover, manual switchover, WTR state,
          or exercise command.";
       reference
         "RFC 4427: Recovery (Protection and Restoration) Terminology
          for Generalized Multi-Protocol Label Switching (GMPLS)";
     }

     identity switching-capabilities {
       description
         "Base identity for interface switching capabilities.";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity switching-psc1 {
       base switching-capabilities;
       description
         "Packet-Switch Capable-1 (PSC-1).";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity switching-evpl {
       base switching-capabilities;
       description
         "Ethernet Virtual Private Line (EVPL).";
       reference
         "RFC 6004: Generalized MPLS (GMPLS) Support for Metro Ethernet
          Forum and G.8011 Ethernet Service Switching";
     }

     identity switching-l2sc {
       base switching-capabilities;
       description
         "Layer-2 Switch Capable (L2SC).";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity switching-tdm {
       base switching-capabilities;
       description
         "Time-Division-Multiplex Capable (TDM).";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity switching-otn {
       base switching-capabilities;
       description
         "OTN-TDM capable.";
       reference
         "RFC 7138: Traffic Engineering Extensions to OSPF for GMPLS
          Control of Evolving G.709 Optical Transport Networks";
     }

     identity switching-dcsc {
       base switching-capabilities;
       description
         "Data Channel Switching Capable (DCSC).";
       reference
         "RFC 6002: Generalized MPLS (GMPLS) Data Channel
          Switching Capable (DCSC) and Channel Set Label Extensions";
     }

     identity switching-lsc {
       base switching-capabilities;
       description
         "Lambda-Switch Capable (LSC).";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity switching-fsc {
       base switching-capabilities;
       description
         "Fiber-Switch Capable (FSC).";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity lsp-encoding-types {
       description
         "Base identity for encoding types.";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity lsp-encoding-packet {
       base lsp-encoding-types;
       description
         "Packet LSP encoding.";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity lsp-encoding-ethernet {
       base lsp-encoding-types;
       description
         "Ethernet LSP encoding.";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity lsp-encoding-pdh {
       base lsp-encoding-types;
       description
         "ANSI/ETSI PDH LSP encoding.";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity lsp-encoding-sdh {
       base lsp-encoding-types;
       description
         "SDH ITU-T G.707 / SONET ANSI T1.105 LSP encoding.";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity lsp-encoding-digital-wrapper {
       base lsp-encoding-types;
       description
         "Digital Wrapper LSP encoding.";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity lsp-encoding-lambda {
       base lsp-encoding-types;
       description
         "Lambda (photonic) LSP encoding.";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity lsp-encoding-fiber {
       base lsp-encoding-types;
       description
         "Fiber LSP encoding.";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity lsp-encoding-fiber-channel {
       base lsp-encoding-types;
       description
         "FiberChannel LSP encoding.";
       reference
         "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Functional Description";
     }

     identity lsp-encoding-oduk {
       base lsp-encoding-types;
       description
         "G.709 ODUk (Digital Path) LSP encoding.";
       reference
         "RFC 4328: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Extensions for G.709 Optical Transport Networks
          Control";
     }

     identity lsp-encoding-optical-channel {
       base lsp-encoding-types;
       description
         "G.709 Optical Channel LSP encoding.";
       reference
         "RFC 4328: Generalized Multi-Protocol Label Switching (GMPLS)
          Signaling Extensions for G.709 Optical Transport Networks
          Control";
     }

     identity lsp-encoding-line {
       base lsp-encoding-types;
       description
         "Line (e.g., 8B/10B) LSP encoding.";
       reference
         "RFC 6004: Generalized MPLS (GMPLS) Support for Metro
          Ethernet Forum and G.8011 Ethernet Service Switching";
     }

     identity path-signaling-type {
       description
         "Base identity from which specific LSP path setup types
          are derived.";
     }

     identity path-setup-static {
       base path-signaling-type;
       description
         "Static LSP provisioning path setup.";
     }

     identity path-setup-rsvp {
       base path-signaling-type;
       description
         "RSVP-TE signaling path setup.";
       reference
         "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels";
     }

     identity path-setup-sr {
       base path-signaling-type;
       description
         "Segment-routing path setup.";
     }

     identity path-scope-type {
       description
         "Base identity from which specific path scope types are
          derived.";
     }

     identity path-scope-segment {
       base path-scope-type;
       description
         "Path scope segment.";
       reference
         "RFC 4873: GMPLS Segment Recovery";
     }

     identity path-scope-end-to-end {
       base path-scope-type;
       description
         "Path scope end to end.";
       reference
         "RFC 4873: GMPLS Segment Recovery";
     }

     identity route-usage-type {
       description
         "Base identity for route usage.";
     }

     identity route-include-object {
       base route-usage-type;
       description
         "'Include route' object.";
     }

     identity route-exclude-object {
       base route-usage-type;
       description
         "'Exclude route' object.";
       reference
         "RFC 4874: Exclude Routes - Extension to Resource ReserVation
          Protocol-Traffic Engineering (RSVP-TE)";
     }

     identity route-exclude-srlg {
       base route-usage-type;
       description
         "Excludes SRLGs.";
       reference
         "RFC 4874: Exclude Routes - Extension to Resource ReserVation
          Protocol-Traffic Engineering (RSVP-TE)";
     }

     identity path-metric-type {
       description
         "Base identity for the path metric type.";
     }

     identity path-metric-te {
       base path-metric-type;
       description
         "TE path metric.";
       reference
         "RFC 3785: Use of Interior Gateway Protocol (IGP) Metric as a
          second MPLS Traffic Engineering (TE) Metric";
     }

     identity path-metric-igp {
       base path-metric-type;
       description
         "IGP path metric.";
       reference
         "RFC 3785: Use of Interior Gateway Protocol (IGP) Metric as a
          second MPLS Traffic Engineering (TE) Metric";
     }

     identity path-metric-hop {
       base path-metric-type;
       description
         "Hop path metric.";
     }

     identity path-metric-delay-average {
       base path-metric-type;
       description
         "Average unidirectional link delay.";
       reference
         "RFC 7471: OSPF Traffic Engineering (TE) Metric Extensions";
     }

     identity path-metric-delay-minimum {
       base path-metric-type;
       description
         "Minimum unidirectional link delay.";
       reference
         "RFC 7471: OSPF Traffic Engineering (TE) Metric Extensions";
     }

     identity path-metric-residual-bandwidth {
       base path-metric-type;
       description
         "Unidirectional Residual Bandwidth, which is defined to be
          Maximum Bandwidth (RFC 3630) minus the bandwidth currently
          allocated to LSPs.";
       reference
         "RFC 3630: Traffic Engineering (TE) Extensions to OSPF
          Version 2
          RFC 7471: OSPF Traffic Engineering (TE) Metric Extensions";
     }

     identity path-metric-optimize-includes {
       base path-metric-type;
       description
         "A metric that optimizes the number of included resources
          specified in a set.";
     }

     identity path-metric-optimize-excludes {
       base path-metric-type;
       description
         "A metric that optimizes to a maximum the number of excluded
          resources specified in a set.";
     }

     identity path-tiebreaker-type {
       description
         "Base identity for the path tiebreaker type.";
     }

     identity path-tiebreaker-minfill {
       base path-tiebreaker-type;
       description
         "Min-Fill LSP path placement.";
     }

     identity path-tiebreaker-maxfill {
       base path-tiebreaker-type;
       description
         "Max-Fill LSP path placement.";
     }

     identity path-tiebreaker-random {
       base path-tiebreaker-type;
       description
         "Random LSP path placement.";
     }

     identity resource-affinities-type {
       description
         "Base identity for resource class affinities.";
       reference
         "RFC 2702: Requirements for Traffic Engineering Over MPLS";
     }

     identity resource-aff-include-all {
       base resource-affinities-type;
       description
         "The set of attribute filters associated with a
          tunnel, all of which must be present for a link
          to be acceptable.";
       reference
         "RFC 2702: Requirements for Traffic Engineering Over MPLS
          RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels";
     }

     identity resource-aff-include-any {
       base resource-affinities-type;
       description
         "The set of attribute filters associated with a
          tunnel, any of which must be present for a link
          to be acceptable.";
       reference
         "RFC 2702: Requirements for Traffic Engineering Over MPLS
          RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels";
     }

     identity resource-aff-exclude-any {
       base resource-affinities-type;
       description
         "The set of attribute filters associated with a
          tunnel, any of which renders a link unacceptable.";
       reference
         "RFC 2702: Requirements for Traffic Engineering Over MPLS
          RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels";
     }

     identity te-optimization-criterion {
       description
         "Base identity for the TE optimization criteria.";
       reference
         "RFC 3272: Overview and Principles of Internet Traffic
          Engineering";
     }

     identity not-optimized {
       base te-optimization-criterion;
       description
         "Optimization is not applied.";
     }

     identity cost {
       base te-optimization-criterion;
       description
         "Optimized on cost.";
       reference
         "RFC 5541: Encoding of Objective Functions in the Path
          Computation Element Communication Protocol (PCEP)";
     }

     identity delay {
       base te-optimization-criterion;
       description
         "Optimized on delay.";
       reference
         "RFC 5541: Encoding of Objective Functions in the Path
          Computation Element Communication Protocol (PCEP)";
     }

     identity path-computation-srlg-type {
       description
         "Base identity for SRLG path computation.";
     }

     identity srlg-ignore {
       base path-computation-srlg-type;
       description
         "Ignores SRLGs in the path computation.";
     }

     identity srlg-strict {
       base path-computation-srlg-type;
       description
         "Includes a strict SRLG check in the path computation.";
     }

     identity srlg-preferred {
       base path-computation-srlg-type;
       description
         "Includes a preferred SRLG check in the path computation.";
     }

     identity srlg-weighted {
       base path-computation-srlg-type;
       description
         "Includes a weighted SRLG check in the path computation.";
     }

     /**
      * TE bandwidth groupings
      **/

     grouping te-bandwidth {
       description
         "This grouping defines the generic TE bandwidth.
          For some known data-plane technologies, specific modeling
          structures are specified.  The string-encoded 'te-bandwidth'
          type is used for unspecified technologies.
          The modeling structure can be augmented later for other
          technologies.";
       container te-bandwidth {
         description
           "Container that specifies TE bandwidth.  The choices
            can be augmented for specific data-plane technologies.";
         choice technology {
           default "generic";
           description
             "Data-plane technology type.";
           case generic {
             leaf generic {
               type te-bandwidth;
               description
                 "Bandwidth specified in a generic format.";
             }
           }
         }
       }
     }

     /**
      * TE label groupings
      **/

     grouping te-label {
       description
         "This grouping defines the generic TE label.
          The modeling structure can be augmented for each technology.
          For unspecified technologies, 'rt-types:generalized-label'
          is used.";
       container te-label {
         description
           "Container that specifies the TE label.  The choices can
            be augmented for specific data-plane technologies.";
         choice technology {
           default "generic";
           description
             "Data-plane technology type.";
           case generic {
             leaf generic {
               type rt-types:generalized-label;
               description
                 "TE label specified in a generic format.";
             }
           }
         }
         leaf direction {
           type te-label-direction;
           default "forward";
           description
             "Label direction.";
         }
       }
     }

     grouping te-topology-identifier {
       description
         "Augmentation for a TE topology.";
       container te-topology-identifier {
         description
           "TE topology identifier container.";
         leaf provider-id {
           type te-global-id;
           default "0";
           description
             "An identifier to uniquely identify a provider.
              If omitted, it assumes that the topology provider ID
              value = 0 (the default).";
         }
         leaf client-id {
           type te-global-id;
           default "0";
           description
             "An identifier to uniquely identify a client.
              If omitted, it assumes that the topology client ID
              value = 0 (the default).";
         }
         leaf topology-id {
           type te-topology-id;
           default "";
           description
             "When the datastore contains several topologies,
              'topology-id' distinguishes between them.  If omitted,
              the default (empty) string for this leaf is assumed.";
         }
       }
     }

     /**
      * TE performance metrics groupings
      **/

     grouping performance-metrics-one-way-delay-loss {
       description
         "Performance Metrics (PM) information in real time that can
          be applicable to links or connections.  PM defined in this
          grouping are applicable to generic TE PM as well as packet TE
          PM.";
       reference
         "RFC 7471: OSPF Traffic Engineering (TE) Metric Extensions
          RFC 7823: Performance-Based Path Selection for Explicitly
          Routed Label Switched Paths (LSPs) Using TE Metric
          Extensions
          RFC 8570: IS-IS Traffic Engineering (TE) Metric Extensions";
       leaf one-way-delay {
         type uint32 {
           range "0..16777215";
         }
         description
           "One-way delay or latency in microseconds.";
       }
       leaf one-way-delay-normality {
         type te-types:performance-metrics-normality;
         description
           "One-way delay normality.";
       }
     }

     grouping performance-metrics-two-way-delay-loss {
       description
         "PM information in real time that can be applicable to links or
          connections.  PM defined in this grouping are applicable to
          generic TE PM as well as packet TE PM.";
       reference
         "RFC 7471: OSPF Traffic Engineering (TE) Metric Extensions
          RFC 7823: Performance-Based Path Selection for Explicitly
          Routed Label Switched Paths (LSPs) Using TE Metric
          Extensions
          RFC 8570: IS-IS Traffic Engineering (TE) Metric Extensions";
       leaf two-way-delay {
         type uint32 {
           range "0..16777215";
         }
         description
           "Two-way delay or latency in microseconds.";
       }
       leaf two-way-delay-normality {
         type te-types:performance-metrics-normality;
         description
           "Two-way delay normality.";
       }
     }

     grouping performance-metrics-one-way-bandwidth {
       description
         "PM information in real time that can be applicable to links.
          PM defined in this grouping are applicable to generic TE PM
          as well as packet TE PM.";
       reference
         "RFC 7471: OSPF Traffic Engineering (TE) Metric Extensions
          RFC 7823: Performance-Based Path Selection for Explicitly
          Routed Label Switched Paths (LSPs) Using TE Metric
          Extensions
          RFC 8570: IS-IS Traffic Engineering (TE) Metric Extensions";
       leaf one-way-residual-bandwidth {
         type rt-types:bandwidth-ieee-float32;
         units "bytes per second";
         default "0x0p0";
         description
           "Residual bandwidth that subtracts tunnel reservations from
            Maximum Bandwidth (or link capacity) (RFC 3630) and
            provides an aggregated remainder across QoS classes.";
         reference
           "RFC 3630: Traffic Engineering (TE) Extensions to OSPF
            Version 2";
       }
       leaf one-way-residual-bandwidth-normality {
         type te-types:performance-metrics-normality;
         default "normal";
         description
           "Residual bandwidth normality.";
       }
       leaf one-way-available-bandwidth {
         type rt-types:bandwidth-ieee-float32;
         units "bytes per second";
         default "0x0p0";
         description
           "Available bandwidth that is defined to be residual
            bandwidth minus the measured bandwidth used for the
            actual forwarding of non-RSVP-TE LSP packets.  For a
            bundled link, available bandwidth is defined to be the
            sum of the component link available bandwidths.";
       }
       leaf one-way-available-bandwidth-normality {
         type te-types:performance-metrics-normality;
         default "normal";
         description
           "Available bandwidth normality.";
       }
       leaf one-way-utilized-bandwidth {
         type rt-types:bandwidth-ieee-float32;
         units "bytes per second";
         default "0x0p0";
         description
           "Bandwidth utilization that represents the actual
            utilization of the link (i.e., as measured in the router).
            For a bundled link, bandwidth utilization is defined to
            be the sum of the component link bandwidth utilizations.";
       }
       leaf one-way-utilized-bandwidth-normality {
         type te-types:performance-metrics-normality;
         default "normal";
         description
           "Bandwidth utilization normality.";
       }
     }

     grouping one-way-performance-metrics {
       description
         "One-way PM throttle grouping.";
       leaf one-way-delay {
         type uint32 {
           range "0..16777215";
         }
         default "0";
         description
           "One-way delay or latency in microseconds.";
       }
       leaf one-way-residual-bandwidth {
         type rt-types:bandwidth-ieee-float32;
         units "bytes per second";
         default "0x0p0";
         description
           "Residual bandwidth that subtracts tunnel reservations from
            Maximum Bandwidth (or link capacity) (RFC 3630) and
            provides an aggregated remainder across QoS classes.";
         reference
           "RFC 3630: Traffic Engineering (TE) Extensions to OSPF
            Version 2";
       }
       leaf one-way-available-bandwidth {
         type rt-types:bandwidth-ieee-float32;
         units "bytes per second";
         default "0x0p0";
         description
           "Available bandwidth that is defined to be residual
            bandwidth minus the measured bandwidth used for the
            actual forwarding of non-RSVP-TE LSP packets.  For a
            bundled link, available bandwidth is defined to be the
            sum of the component link available bandwidths.";
       }
       leaf one-way-utilized-bandwidth {
         type rt-types:bandwidth-ieee-float32;
         units "bytes per second";
         default "0x0p0";
         description
           "Bandwidth utilization that represents the actual
            utilization of the link (i.e., as measured in the router).
            For a bundled link, bandwidth utilization is defined to
            be the sum of the component link bandwidth utilizations.";
       }
     }

     grouping two-way-performance-metrics {
       description
         "Two-way PM throttle grouping.";
       leaf two-way-delay {
         type uint32 {
           range "0..16777215";
         }
         default "0";
         description
           "Two-way delay or latency in microseconds.";
       }
     }

     grouping performance-metrics-thresholds {
       description
         "Grouping for configurable thresholds for measured
          attributes.";
       uses one-way-performance-metrics;
       uses two-way-performance-metrics;
     }

     grouping performance-metrics-attributes {
       description
         "Contains PM attributes.";
       container performance-metrics-one-way {
         description
           "One-way link performance information in real time.";
         reference
           "RFC 7471: OSPF Traffic Engineering (TE) Metric Extensions
            RFC 7823: Performance-Based Path Selection for Explicitly
            Routed Label Switched Paths (LSPs) Using TE Metric
            Extensions
            RFC 8570: IS-IS Traffic Engineering (TE) Metric Extensions";
         uses performance-metrics-one-way-delay-loss;
         uses performance-metrics-one-way-bandwidth;
       }
       container performance-metrics-two-way {
         description
           "Two-way link performance information in real time.";
         reference
           "RFC 6374: Packet Loss and Delay Measurement for MPLS
            Networks";
         uses performance-metrics-two-way-delay-loss;
       }
     }

     grouping performance-metrics-throttle-container {
       description
         "Controls PM throttling.";
       container throttle {
         must 'suppression-interval >= measure-interval' {
           error-message "'suppression-interval' cannot be less than "
                       + "'measure-interval'.";
           description
             "Constraint on 'suppression-interval' and
              'measure-interval'.";
         }
         description
           "Link performance information in real time.";
         reference
           "RFC 7471: OSPF Traffic Engineering (TE) Metric Extensions
            RFC 7823: Performance-Based Path Selection for Explicitly
            Routed Label Switched Paths (LSPs) Using TE Metric
            Extensions
            RFC 8570: IS-IS Traffic Engineering (TE) Metric Extensions";
         leaf one-way-delay-offset {
           type uint32 {
             range "0..16777215";
           }
           default "0";
           description
             "Offset value to be added to the measured delay value.";
         }
         leaf measure-interval {
           type uint32;
           default "30";
           description
             "Interval, in seconds, to measure the extended metric
              values.";
         }
         leaf advertisement-interval {
           type uint32;
           default "0";
           description
             "Interval, in seconds, to advertise the extended metric
              values.";
         }
         leaf suppression-interval {
           type uint32 {
             range "1..max";
           }
           default "120";
           description
             "Interval, in seconds, to suppress advertisement of the
              extended metric values.";
           reference
             "RFC 8570: IS-IS Traffic Engineering (TE) Metric
              Extensions, Section 6";
         }
         container threshold-out {
           uses performance-metrics-thresholds;
           description
             "If the measured parameter falls outside an upper bound
              for all but the minimum-delay metric (or a lower bound
              for the minimum-delay metric only) and the advertised
              value is not already outside that bound, an 'anomalous'
              announcement (anomalous bit set) will be triggered.";
         }
         container threshold-in {
           uses performance-metrics-thresholds;
           description
             "If the measured parameter falls inside an upper bound
              for all but the minimum-delay metric (or a lower bound
              for the minimum-delay metric only) and the advertised
              value is not already inside that bound, a 'normal'
              announcement (anomalous bit cleared) will be triggered.";
         }
         container threshold-accelerated-advertisement {
           description
             "When the difference between the last advertised value and
              the current measured value exceeds this threshold, an
              'anomalous' announcement (anomalous bit set) will be
              triggered.";
           uses performance-metrics-thresholds;
         }
       }
     }

     /**
      * TE tunnel generic groupings
      **/

     grouping explicit-route-hop {
       description
         "The explicit route entry grouping.";
       choice type {
         description
           "The explicit route entry type.";
         case numbered-node-hop {
           container numbered-node-hop {
             leaf node-id {
               type te-node-id;
               mandatory true;
               description
                 "The identifier of a node in the TE topology.";
             }
             leaf hop-type {
               type te-hop-type;
               default "strict";
               description
                 "Strict or loose hop.";
             }
             description
               "Numbered node route hop.";
             reference
               "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels,
                Section 4.3, EXPLICIT_ROUTE in RSVP-TE
                RFC 3477: Signalling Unnumbered Links in Resource
                ReSerVation Protocol - Traffic Engineering (RSVP-TE)";
           }
         }
         case numbered-link-hop {
           container numbered-link-hop {
             leaf link-tp-id {
               type te-tp-id;
               mandatory true;
               description
                 "TE Link Termination Point (LTP) identifier.";
             }
             leaf hop-type {
               type te-hop-type;
               default "strict";
               description
                 "Strict or loose hop.";
             }
             leaf direction {
               type te-link-direction;
               default "outgoing";
               description
                 "Link route object direction.";
             }
             description
               "Numbered link explicit route hop.";
             reference
               "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels,
                Section 4.3, EXPLICIT_ROUTE in RSVP-TE
                RFC 3477: Signalling Unnumbered Links in Resource
                ReSerVation Protocol - Traffic Engineering (RSVP-TE)";
           }
         }
         case unnumbered-link-hop {
           container unnumbered-link-hop {
             leaf link-tp-id {
               type te-tp-id;
               mandatory true;
               description
                 "TE LTP identifier.  The combination of the TE link ID
                  and the TE node ID is used to identify an unnumbered
                  TE link.";
             }
             leaf node-id {
               type te-node-id;
               mandatory true;
               description
                 "The identifier of a node in the TE topology.";
             }
             leaf hop-type {
               type te-hop-type;
               default "strict";
               description
                 "Strict or loose hop.";
             }
             leaf direction {
               type te-link-direction;
               default "outgoing";
               description
                 "Link route object direction.";
             }
             description
               "Unnumbered link explicit route hop.";
             reference
               "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels,
                Section 4.3, EXPLICIT_ROUTE in RSVP-TE
                RFC 3477: Signalling Unnumbered Links in Resource
                ReSerVation Protocol - Traffic Engineering (RSVP-TE)";
           }
         }
         case as-number {
           container as-number-hop {
             leaf as-number {
               type inet:as-number;
               mandatory true;
               description
                 "The Autonomous System (AS) number.";
             }
             leaf hop-type {
               type te-hop-type;
               default "strict";
               description
                 "Strict or loose hop.";
             }
             description
               "AS explicit route hop.";
           }
         }
         case label {
           container label-hop {
             description
               "Label hop type.";
             uses te-label;
           }
           description
             "The label explicit route hop type.";
         }
       }
     }

     grouping record-route-state {
       description
         "The Record Route grouping.";
       leaf index {
         type uint32;
         description
           "Record Route hop index.  The index is used to
            identify an entry in the list.  The order of entries
            is defined by the user without relying on key values.";
       }
       choice type {
         description
           "The Record Route entry type.";
         case numbered-node-hop {
           container numbered-node-hop {
             description
               "Numbered node route hop container.";
             leaf node-id {
               type te-node-id;
               mandatory true;
               description
                 "The identifier of a node in the TE topology.";
             }
             leaf-list flags {
               type path-attribute-flags;
               description
                 "Path attributes flags.";
               reference
                 "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels
                  RFC 4090: Fast Reroute Extensions to RSVP-TE for LSP
                  Tunnels
                  RFC 4561: Definition of a Record Route Object (RRO)
                  Node-Id Sub-Object";
             }
           }
           description
             "Numbered node route hop.";
         }
         case numbered-link-hop {
           container numbered-link-hop {
             description
               "Numbered link route hop container.";
             leaf link-tp-id {
               type te-tp-id;
               mandatory true;
               description
                 "Numbered TE LTP identifier.";
             }
             leaf-list flags {
               type path-attribute-flags;
               description
                 "Path attributes flags.";
               reference
                 "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels
                  RFC 4090: Fast Reroute Extensions to RSVP-TE for LSP
                  Tunnels
                  RFC 4561: Definition of a Record Route Object (RRO)
                  Node-Id Sub-Object";
             }
           }
           description
             "Numbered link route hop.";
         }
         case unnumbered-link-hop {
           container unnumbered-link-hop {
             leaf link-tp-id {
               type te-tp-id;
               mandatory true;
               description
                 "TE LTP identifier.  The combination of the TE link ID
                  and the TE node ID is used to identify an unnumbered
                  TE link.";
             }
             leaf node-id {
               type te-node-id;
               description
                 "The identifier of a node in the TE topology.";
             }
             leaf-list flags {
               type path-attribute-flags;
               description
                 "Path attributes flags.";
               reference
                 "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels
                  RFC 4090: Fast Reroute Extensions to RSVP-TE for LSP
                  Tunnels
                  RFC 4561: Definition of a Record Route Object (RRO)
                  Node-Id Sub-Object";
             }
             description
               "Unnumbered link Record Route hop.";
             reference
               "RFC 3477: Signalling Unnumbered Links in Resource
                ReSerVation Protocol - Traffic Engineering (RSVP-TE)";
           }
           description
             "Unnumbered link route hop.";
         }
         case label {
           container label-hop {
             description
               "Label route hop type.";
             uses te-label;
             leaf-list flags {
               type path-attribute-flags;
               description
                 "Path attributes flags.";
               reference
                 "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels
                  RFC 4090: Fast Reroute Extensions to RSVP-TE for LSP
                  Tunnels
                  RFC 4561: Definition of a Record Route Object (RRO)
                  Node-Id Sub-Object";
             }
           }
           description
             "The label Record Route entry types.";
         }
       }
     }

     grouping label-restriction-info {
       description
         "Label set item information.";
       leaf restriction {
         type enumeration {
           enum inclusive {
             description
               "The label or label range is inclusive.";
           }
           enum exclusive {
             description
               "The label or label range is exclusive.";
           }
         }
         default "inclusive";
         description
           "Indicates whether the list item is inclusive or exclusive.";
       }
       leaf index {
         type uint32;
         description
           "The index of the label restriction list entry.";
       }
       container label-start {
         must "(not(../label-end/te-label/direction) and"
            + " not(te-label/direction))"
            + " or "
            + "(../label-end/te-label/direction = te-label/direction)"
            + " or "
            + "(not(te-label/direction) and"
            + " (../label-end/te-label/direction = 'forward'))"
            + " or "
            + "(not(../label-end/te-label/direction) and"
            + " (te-label/direction = 'forward'))" {
           error-message "'label-start' and 'label-end' must have the "
                       + "same direction.";
         }
         description
           "This is the starting label if a label range is specified.
            This is the label value if a single label is specified,
            in which case the 'label-end' attribute is not set.";
         uses te-label;
       }
       container label-end {
         must "(not(../label-start/te-label/direction) and"
            + " not(te-label/direction))"
            + " or "
            + "(../label-start/te-label/direction = te-label/direction)"
            + " or "
            + "(not(te-label/direction) and"
            + " (../label-start/te-label/direction = 'forward'))"
            + " or "
            + "(not(../label-start/te-label/direction) and"
            + " (te-label/direction = 'forward'))" {
           error-message "'label-start' and 'label-end' must have the "
                       + "same direction.";
         }
         description
           "This is the ending label if a label range is specified.
            This attribute is not set if a single label is specified.";
         uses te-label;
       }
       container label-step {
         description
           "The step increment between labels in the label range.
            The label start/end values will have to be consistent
            with the sign of label step.  For example,
            'label-start' < 'label-end' enforces 'label-step' > 0
            'label-start' > 'label-end' enforces 'label-step' < 0.";
         choice technology {
           default "generic";
           description
             "Data-plane technology type.";
           case generic {
             leaf generic {
               type int32;
               default "1";
               description
                 "Label range step.";
             }
           }
         }
       }
       leaf range-bitmap {
         type yang:hex-string;
         description
           "When there are gaps between 'label-start' and 'label-end',
            this attribute is used to specify the positions
            of the used labels.  This is represented in big endian as
            'hex-string'.
            The most significant byte in the hex-string is the farthest
            to the left in the byte sequence.  Leading zero bytes in the
            configured value may be omitted for brevity.
            Each bit position in the 'range-bitmap' 'hex-string' maps
            to a label in the range derived from 'label-start'.

            For example, assuming that 'label-start' = 16000 and
            'range-bitmap' = 0x01000001, then:

            - bit position (0) is set, and the corresponding mapped
              label from the range is 16000 + (0 * 'label-step') or
              16000 for default 'label-step' = 1.
            - bit position (24) is set, and the corresponding mapped
              label from the range is 16000 + (24 * 'label-step') or
              16024 for default 'label-step' = 1.";
       }
     }

     grouping label-set-info {
       description
         "Grouping for the list of label restrictions specifying what
          labels may or may not be used.";
       container label-restrictions {
         description
           "The label restrictions container.";
         list label-restriction {
           key "index";
           description
             "The absence of the label restrictions container implies
              that all labels are acceptable; otherwise, only restricted
              labels are available.";
           reference
             "RFC 7579: General Network Element Constraint Encoding
              for GMPLS-Controlled Networks";
           uses label-restriction-info;
         }
       }
     }

     grouping optimization-metric-entry {
       description
         "Optimization metrics configuration grouping.";
       leaf metric-type {
         type identityref {
           base path-metric-type;
         }
         description
           "Identifies the 'metric-type' that the path computation
            process uses for optimization.";
       }
       leaf weight {
         type uint8;
         default "1";
         description
           "TE path metric normalization weight.";
       }
       container explicit-route-exclude-objects {
         when "../metric-type = "
            + "'te-types:path-metric-optimize-excludes'";
         description
           "Container for the 'exclude route' object list.";
         uses path-route-exclude-objects;
       }
       container explicit-route-include-objects {
         when "../metric-type = "
            + "'te-types:path-metric-optimize-includes'";
         description
           "Container for the 'include route' object list.";
         uses path-route-include-objects;
       }
     }

     grouping common-constraints {
       description
         "Common constraints grouping that can be set on
          a constraint set or directly on the tunnel.";
       uses te-bandwidth {
         description
           "A requested bandwidth to use for path computation.";
       }
       leaf link-protection {
         type identityref {
           base link-protection-type;
         }
         default "te-types:link-protection-unprotected";
         description
           "Link protection type required for the links included
            in the computed path.";
         reference
           "RFC 4202: Routing Extensions in Support of
            Generalized Multi-Protocol Label Switching (GMPLS)";
       }
       leaf setup-priority {
         type uint8 {
           range "0..7";
         }
         default "7";
         description
           "TE LSP requested setup priority.";
         reference
           "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels";
       }
       leaf hold-priority {
         type uint8 {
           range "0..7";
         }
         default "7";
         description
           "TE LSP requested hold priority.";
         reference
           "RFC 3209: RSVP-TE: Extensions to RSVP for LSP Tunnels";
       }
       leaf signaling-type {
         type identityref {
           base path-signaling-type;
         }
         default "te-types:path-setup-rsvp";
         description
           "TE tunnel path signaling type.";
       }
     }

     grouping tunnel-constraints {
       description
         "Tunnel constraints grouping that can be set on
          a constraint set or directly on the tunnel.";
       uses te-topology-identifier;
       uses common-constraints;
     }

     grouping path-constraints-route-objects {
       description
         "List of route entries to be included or excluded when
          performing the path computation.";
       container explicit-route-objects-always {
         description
           "Container for the 'exclude route' object list.";
         list route-object-exclude-always {
           key "index";
           ordered-by user;
           description
             "List of route objects to always exclude from the path
              computation.";
           leaf index {
             type uint32;
             description
               "Explicit Route Object index.  The index is used to
                identify an entry in the list.  The order of entries
                is defined by the user without relying on key values.";
           }
           uses explicit-route-hop;
         }
         list route-object-include-exclude {
           key "index";
           ordered-by user;
           description
             "List of route objects to include or exclude in the path
              computation.";
           leaf explicit-route-usage {
             type identityref {
               base route-usage-type;
             }
             default "te-types:route-include-object";
             description
               "Indicates whether to include or exclude the
                route object.  The default is to include it.";
           }
           leaf index {
             type uint32;
             description
               "Route object include-exclude index.  The index is used
                to identify an entry in the list.  The order of entries
                is defined by the user without relying on key values.";
           }
           uses explicit-route-hop {
             augment "type" {
               case srlg {
                 container srlg {
                   description
                     "SRLG container.";
                   leaf srlg {
                     type uint32;
                     description
                       "SRLG value.";
                   }
                 }
                 description
                   "An SRLG value to be included or excluded.";
               }
               description
                 "Augmentation for a generic explicit route for SRLG
                  exclusion.";
             }
           }
         }
       }
     }

     grouping path-route-include-objects {
       description
         "List of route objects to be included when performing
          the path computation.";
       list route-object-include-object {
         key "index";
         ordered-by user;
         description
           "List of Explicit Route Objects to be included in the
            path computation.";
         leaf index {
           type uint32;
           description
             "Route object entry index.  The index is used to
              identify an entry in the list.  The order of entries
              is defined by the user without relying on key values.";
         }
         uses explicit-route-hop;
       }
     }

     grouping path-route-exclude-objects {
       description
         "List of route objects to be excluded when performing
          the path computation.";
       list route-object-exclude-object {
         key "index";
         ordered-by user;
         description
           "List of Explicit Route Objects to be excluded in the
            path computation.";
         leaf index {
           type uint32;
           description
             "Route object entry index.  The index is used to
              identify an entry in the list.  The order of entries
              is defined by the user without relying on key values.";
         }
         uses explicit-route-hop {
           augment "type" {
             case srlg {
               container srlg {
                 description
                   "SRLG container.";
                 leaf srlg {
                   type uint32;
                   description
                     "SRLG value.";
                 }
               }
               description
                 "An SRLG value to be included or excluded.";
             }
             description
               "Augmentation for a generic explicit route for SRLG
                exclusion.";
           }
         }
       }
     }

     grouping generic-path-metric-bounds {
       description
         "TE path metric bounds grouping.";
       container path-metric-bounds {
         description
           "TE path metric bounds container.";
         list path-metric-bound {
           key "metric-type";
           description
             "List of TE path metric bounds.";
           leaf metric-type {
             type identityref {
               base path-metric-type;
             }
             description
               "Identifies an entry in the list of 'metric-type' items
                bound for the TE path.";
           }
           leaf upper-bound {
             type uint64;
             default "0";
             description
               "Upper bound on the end-to-end TE path metric.  A zero
                indicates an unbounded upper limit for the specific
                'metric-type'.";
           }
         }
       }
     }

     grouping generic-path-optimization {
       description
         "TE generic path optimization grouping.";
       container optimizations {
         description
           "The objective function container that includes
            attributes to impose when computing a TE path.";
         choice algorithm {
           description
             "Optimizations algorithm.";
           case metric {
             if-feature "path-optimization-metric";
             /* Optimize by metric */
             list optimization-metric {
               key "metric-type";
               description
                 "TE path metric type.";
               uses optimization-metric-entry;
             }
             /* Tiebreakers */
             container tiebreakers {
               description
                 "Container for the list of tiebreakers.";
               list tiebreaker {
                 key "tiebreaker-type";
                 description
                   "The list of tiebreaker criteria to apply on an
                    equally favored set of paths, in order to pick
                    the best.";
                 leaf tiebreaker-type {
                   type identityref {
                     base path-metric-type;
                   }
                   description
                     "Identifies an entry in the list of tiebreakers.";
                 }
               }
             }
           }
           case objective-function {
             if-feature "path-optimization-objective-function";
             /* Objective functions */
             container objective-function {
               description
                 "The objective function container that includes
                  attributes to impose when computing a TE path.";
               leaf objective-function-type {
                 type identityref {
                   base objective-function-type;
                 }
                 default "te-types:of-minimize-cost-path";
                 description
                   "Objective function entry.";
               }
             }
           }
         }
       }
     }

     grouping generic-path-affinities {
       description
         "Path affinities grouping.";
       container path-affinities-values {
         description
           "Path affinities represented as values.";
         list path-affinities-value {
           key "usage";
           description
             "List of named affinity constraints.";
           leaf usage {
             type identityref {
               base resource-affinities-type;
             }
             description
               "Identifies an entry in the list of value affinity
                constraints.";
           }
           leaf value {
             type admin-groups;
             default "";
             description
               "The affinity value.  The default is empty.";
           }
         }
       }
       container path-affinity-names {
         description
           "Path affinities represented as names.";
         list path-affinity-name {
           key "usage";
           description
             "List of named affinity constraints.";
           leaf usage {
             type identityref {
               base resource-affinities-type;
             }
             description
               "Identifies an entry in the list of named affinity
                constraints.";
           }
           list affinity-name {
             key "name";
             leaf name {
               type string;
               description
                 "Identifies a named affinity entry.";
             }
             description
               "List of named affinities.";
           }
         }
       }
     }

     grouping generic-path-srlgs {
       description
         "Path SRLG grouping.";
       container path-srlgs-lists {
         description
           "Path SRLG properties container.";
         list path-srlgs-list {
           key "usage";
           description
             "List of SRLG values to be included or excluded.";
           leaf usage {
             type identityref {
               base route-usage-type;
             }
             description
               "Identifies an entry in a list of SRLGs to either
                include or exclude.";
           }
           leaf-list values {
             type srlg;
             description
               "List of SRLG values.";
           }
         }
       }
       container path-srlgs-names {
         description
           "Container for the list of named SRLGs.";
         list path-srlgs-name {
           key "usage";
           description
             "List of named SRLGs to be included or excluded.";
           leaf usage {
             type identityref {
               base route-usage-type;
             }
             description
               "Identifies an entry in a list of named SRLGs to either
                include or exclude.";
           }
           leaf-list names {
             type string;
             description
               "List of named SRLGs.";
           }
         }
       }
     }

     grouping generic-path-disjointness {
       description
         "Path disjointness grouping.";
       leaf disjointness {
         type te-path-disjointness;
         description
           "The type of resource disjointness.
            When configured for a primary path, the disjointness level
            applies to all secondary LSPs.  When configured for a
            secondary path, the disjointness level overrides the level
            configured for the primary path.";
       }
     }

     grouping common-path-constraints-attributes {
       description
         "Common path constraints configuration grouping.";
       uses common-constraints;
       uses generic-path-metric-bounds;
       uses generic-path-affinities;
       uses generic-path-srlgs;
     }

     grouping generic-path-constraints {
       description
         "Global named path constraints configuration grouping.";
       container path-constraints {
         description
           "TE named path constraints container.";
         uses common-path-constraints-attributes;
         uses generic-path-disjointness;
       }
     }

     grouping generic-path-properties {
       description
         "TE generic path properties grouping.";
       container path-properties {
         config false;
         description
           "The TE path properties.";
         list path-metric {
           key "metric-type";
           description
             "TE path metric type.";
           leaf metric-type {
             type identityref {
               base path-metric-type;
             }
             description
               "TE path metric type.";
           }
           leaf accumulative-value {
             type uint64;
             description
               "TE path metric accumulative value.";
           }
         }
         uses generic-path-affinities;
         uses generic-path-srlgs;
         container path-route-objects {
           description
             "Container for the list of route objects either returned by
              the computation engine or actually used by an LSP.";
           list path-route-object {
             key "index";
             ordered-by user;
             description
               "List of route objects either returned by the computation
                engine or actually used by an LSP.";
             leaf index {
               type uint32;
               description
                 "Route object entry index.  The index is used to
                  identify an entry in the list.  The order of entries
                  is defined by the user without relying on key
                  values.";
             }
             uses explicit-route-hop;
           }
         }
       }
     }
   }
   <CODE ENDS>

5.  Packet TE Types YANG Module

   The "ietf-te-packet-types" module imports from the "ietf-te-types"
   module defined in Section 4 of this document.

   <CODE BEGINS> file "ietf-te-packet-types@2020-06-10.yang"
   module ietf-te-packet-types {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-te-packet-types";
     prefix te-packet-types;

     /* Import TE generic types */

     import ietf-te-types {
       prefix te-types;
       reference
         "RFC 8776: Common YANG Data Types for Traffic Engineering";
     }

     organization
       "IETF Traffic Engineering Architecture and Signaling (TEAS)
        Working Group";
     contact
       "WG Web:   <https://datatracker.ietf.org/wg/teas/>
        WG List:  <mailto:teas@ietf.org>

        Editor:   Tarek Saad
                  <mailto:tsaad@juniper.net>

        Editor:   Rakesh Gandhi
                  <mailto:rgandhi@cisco.com>

        Editor:   Vishnu Pavan Beeram
                  <mailto:vbeeram@juniper.net>

        Editor:   Xufeng Liu
                  <mailto:xufeng.liu.ietf@gmail.com>

        Editor:   Igor Bryskin
                  <mailto:i_bryskin@yahoo.com>";
     description
       "This YANG module contains a collection of generally useful YANG
        data type definitions specific to MPLS TE.  The model fully
        conforms to the Network Management Datastore Architecture
        (NMDA).

        Copyright (c) 2020 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
        (https://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC 8776; see the
        RFC itself for full legal notices.";

     revision 2020-06-10 {
       description
         "Latest revision of TE MPLS types.";
       reference
         "RFC 8776: Common YANG Data Types for Traffic Engineering";
     }

     /**
      * Typedefs
      */

     typedef te-bandwidth-requested-type {
       type enumeration {
         enum specified {
           description
             "Bandwidth is explicitly specified.";
         }
         enum auto {
           description
             "Bandwidth is automatically computed.";
         }
       }
       description
         "Enumerated type for specifying whether bandwidth is
          explicitly specified or automatically computed.";
     }

     typedef te-class-type {
       type uint8;
       description
         "Diffserv-TE Class-Type.  Defines a set of Traffic Trunks
          crossing a link that is governed by a specific set of
          bandwidth constraints.  Class-Type is used for the purposes
          of link bandwidth allocation, constraint-based routing, and
          admission control.";
       reference
         "RFC 4124: Protocol Extensions for Support of Diffserv-aware
          MPLS Traffic Engineering";
     }

     typedef bc-type {
       type uint8 {
         range "0..7";
       }
       description
         "Diffserv-TE bandwidth constraints as defined in RFC 4124.";
       reference
         "RFC 4124: Protocol Extensions for Support of Diffserv-aware
          MPLS Traffic Engineering";
     }

     typedef bandwidth-kbps {
       type uint64;
       units "Kbps";
       description
         "Bandwidth values, expressed in kilobits per second.";
     }

     typedef bandwidth-mbps {
       type uint64;
       units "Mbps";
       description
         "Bandwidth values, expressed in megabits per second.";
     }

     typedef bandwidth-gbps {
       type uint64;
       units "Gbps";
       description
         "Bandwidth values, expressed in gigabits per second.";
     }

     identity backup-protection-type {
       description
         "Base identity for the backup protection type.";
     }

     identity backup-protection-link {
       base backup-protection-type;
       description
         "Backup provides link protection only.";
     }

     identity backup-protection-node-link {
       base backup-protection-type;
       description
         "Backup offers node (preferred) or link protection.";
     }

     identity bc-model-type {
       description
         "Base identity for the Diffserv-TE Bandwidth Constraints
          Model type.";
       reference
         "RFC 4124: Protocol Extensions for Support of Diffserv-aware
          MPLS Traffic Engineering";
     }

     identity bc-model-rdm {
       base bc-model-type;
       description
         "Russian Dolls Bandwidth Constraints Model type.";
       reference
         "RFC 4127: Russian Dolls Bandwidth Constraints Model for
                    Diffserv-aware MPLS Traffic Engineering";
     }

     identity bc-model-mam {
       base bc-model-type;
       description
         "Maximum Allocation Bandwidth Constraints Model type.";
       reference
         "RFC 4125: Maximum Allocation Bandwidth Constraints Model for
                    Diffserv-aware MPLS Traffic Engineering";
     }

     identity bc-model-mar {
       base bc-model-type;
       description
         "Maximum Allocation with Reservation Bandwidth Constraints
          Model type.";
       reference
         "RFC 4126: Max Allocation with Reservation Bandwidth
          Constraints Model for Diffserv-aware MPLS Traffic Engineering
          & Performance Comparisons";
     }

     grouping performance-metrics-attributes-packet {
       description
         "Contains PM attributes.";
       uses te-types:performance-metrics-attributes {
         augment "performance-metrics-one-way" {
           leaf one-way-min-delay {
             type uint32 {
               range "0..16777215";
             }
             description
               "One-way minimum delay or latency in microseconds.";
           }
           leaf one-way-min-delay-normality {
             type te-types:performance-metrics-normality;
             default "normal";
             description
               "One-way minimum delay or latency normality.";
           }
           leaf one-way-max-delay {
             type uint32 {
               range "0..16777215";
             }
             description
               "One-way maximum delay or latency in microseconds.";
           }
           leaf one-way-max-delay-normality {
             type te-types:performance-metrics-normality;
             default "normal";
             description
               "One-way maximum delay or latency normality.";
           }
           leaf one-way-delay-variation {
             type uint32 {
               range "0..16777215";
             }
             description
               "One-way delay variation in microseconds.";
             reference
               "RFC 5481: Packet Delay Variation Applicability
                Statement, Section 4.2";
           }
           leaf one-way-delay-variation-normality {
             type te-types:performance-metrics-normality;
             default "normal";
             description
               "One-way delay variation normality.";
             reference
               "RFC 7471: OSPF Traffic Engineering (TE) Metric
                Extensions
                RFC 7823: Performance-Based Path Selection for
                Explicitly Routed Label Switched Paths (LSPs) Using
                TE Metric Extensions
                RFC 8570: IS-IS Traffic Engineering (TE) Metric
                Extensions";
           }
           leaf one-way-packet-loss {
             type decimal64 {
               fraction-digits 6;
               range "0..50.331642";
             }
             description
               "One-way packet loss as a percentage of the total traffic
                sent over a configurable interval.  The finest precision
                is 0.000003%, where the maximum is 50.331642%.";
             reference
               "RFC 8570: IS-IS Traffic Engineering (TE) Metric
                Extensions, Section 4.4";
           }
           leaf one-way-packet-loss-normality {
             type te-types:performance-metrics-normality;
             default "normal";
             description
               "Packet loss normality.";
             reference
               "RFC 7471: OSPF Traffic Engineering (TE) Metric
                Extensions
                RFC 7823: Performance-Based Path Selection for
                Explicitly Routed Label Switched Paths (LSPs) Using
                TE Metric Extensions
                RFC 8570: IS-IS Traffic Engineering (TE) Metric
                Extensions";
           }
           description
             "PM one-way packet-specific augmentation for a generic PM
              grouping.";
         }
         augment "performance-metrics-two-way" {
           leaf two-way-min-delay {
             type uint32 {
               range "0..16777215";
             }
             default "0";
             description
               "Two-way minimum delay or latency in microseconds.";
           }
           leaf two-way-min-delay-normality {
             type te-types:performance-metrics-normality;
             default "normal";
             description
               "Two-way minimum delay or latency normality.";
             reference
               "RFC 7471: OSPF Traffic Engineering (TE) Metric
                Extensions
                RFC 7823: Performance-Based Path Selection for
                Explicitly Routed Label Switched Paths (LSPs) Using
                TE Metric Extensions
                RFC 8570: IS-IS Traffic Engineering (TE) Metric
                Extensions";
           }
           leaf two-way-max-delay {
             type uint32 {
               range "0..16777215";
             }
             default "0";
             description
               "Two-way maximum delay or latency in microseconds.";
           }
           leaf two-way-max-delay-normality {
             type te-types:performance-metrics-normality;
             default "normal";
             description
               "Two-way maximum delay or latency normality.";
             reference
               "RFC 7471: OSPF Traffic Engineering (TE) Metric
                Extensions
                RFC 7823: Performance-Based Path Selection for
                Explicitly Routed Label Switched Paths (LSPs) Using
                TE Metric Extensions
                RFC 8570: IS-IS Traffic Engineering (TE) Metric
                Extensions";
           }
           leaf two-way-delay-variation {
             type uint32 {
               range "0..16777215";
             }
             default "0";
             description
               "Two-way delay variation in microseconds.";
             reference
               "RFC 5481: Packet Delay Variation Applicability
                Statement, Section 4.2";
           }
           leaf two-way-delay-variation-normality {
             type te-types:performance-metrics-normality;
             default "normal";
             description
               "Two-way delay variation normality.";
             reference
               "RFC 7471: OSPF Traffic Engineering (TE) Metric
                Extensions
                RFC 7823: Performance-Based Path Selection for
                Explicitly Routed Label Switched Paths (LSPs) Using
                TE Metric Extensions
                RFC 8570: IS-IS Traffic Engineering (TE) Metric
                Extensions";
           }
           leaf two-way-packet-loss {
             type decimal64 {
               fraction-digits 6;
               range "0..50.331642";
             }
             default "0";
             description
               "Two-way packet loss as a percentage of the total traffic
                sent over a configurable interval.  The finest precision
                is 0.000003%.";
           }
           leaf two-way-packet-loss-normality {
             type te-types:performance-metrics-normality;
             default "normal";
             description
               "Two-way packet loss normality.";
           }
           description
             "PM two-way packet-specific augmentation for a generic PM
              grouping.";
           reference
             "RFC 7471: OSPF Traffic Engineering (TE) Metric Extensions
              RFC 7823: Performance-Based Path Selection for
              Explicitly Routed Label Switched Paths (LSPs) Using
              TE Metric Extensions
              RFC 8570: IS-IS Traffic Engineering (TE) Metric
              Extensions";
         }
       }
     }

     grouping one-way-performance-metrics-packet {
       description
         "One-way packet PM throttle grouping.";
       leaf one-way-min-delay {
         type uint32 {
           range "0..16777215";
         }
         default "0";
         description
           "One-way minimum delay or latency in microseconds.";
       }
       leaf one-way-max-delay {
         type uint32 {
           range "0..16777215";
         }
         default "0";
         description
           "One-way maximum delay or latency in microseconds.";
       }
       leaf one-way-delay-variation {
         type uint32 {
           range "0..16777215";
         }
         default "0";
         description
           "One-way delay variation in microseconds.";
       }
       leaf one-way-packet-loss {
         type decimal64 {
           fraction-digits 6;
           range "0..50.331642";
         }
         default "0";
         description
           "One-way packet loss as a percentage of the total traffic
            sent over a configurable interval.  The finest precision is
            0.000003%.";
       }
     }

     grouping two-way-performance-metrics-packet {
       description
         "Two-way packet PM throttle grouping.";
       leaf two-way-min-delay {
         type uint32 {
           range "0..16777215";
         }
         default "0";
         description
           "Two-way minimum delay or latency in microseconds.";
       }
       leaf two-way-max-delay {
         type uint32 {
           range "0..16777215";
         }
         default "0";
         description
           "Two-way maximum delay or latency in microseconds.";
       }
       leaf two-way-delay-variation {
         type uint32 {
           range "0..16777215";
         }
         default "0";
         description
           "Two-way delay variation in microseconds.";
       }
       leaf two-way-packet-loss {
         type decimal64 {
           fraction-digits 6;
           range "0..50.331642";
         }
         default "0";
         description
           "Two-way packet loss as a percentage of the total traffic
            sent over a configurable interval.  The finest precision is
            0.000003%.";
       }
     }

     grouping performance-metrics-throttle-container-packet {
       description
         "Packet PM threshold grouping.";
       uses te-types:performance-metrics-throttle-container {
         augment "throttle/threshold-out" {
           uses one-way-performance-metrics-packet;
           uses two-way-performance-metrics-packet;
           description
             "PM threshold-out packet augmentation for a
              generic grouping.";
         }
         augment "throttle/threshold-in" {
           uses one-way-performance-metrics-packet;
           uses two-way-performance-metrics-packet;
           description
             "PM threshold-in packet augmentation for a
              generic grouping.";
         }
         augment "throttle/threshold-accelerated-advertisement" {
           uses one-way-performance-metrics-packet;
           uses two-way-performance-metrics-packet;
           description
             "PM accelerated advertisement packet augmentation for a
              generic grouping.";
         }
       }
     }
   }
   <CODE ENDS>

6.  IANA Considerations

   This document registers the following URIs in the "ns" subregistry
   within the "IETF XML Registry" [RFC3688].

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

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

   This document registers two YANG modules in the "YANG Module Names"
   registry [RFC6020].

      Name:  ietf-te-types
      Namespace:  urn:ietf:params:xml:ns:yang:ietf-te-types
      Prefix:  te-types
      Reference:  RFC 8776

      Name:  ietf-te-packet-types
      Namespace:  urn:ietf:params:xml:ns:yang:ietf-te-packet-types
      Prefix:  te-packet-types
      Reference:  RFC 8776

7.  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.

   The YANG module in this document defines common TE type definitions
   (e.g., typedef, identity, and grouping statements) in YANG data
   modeling language to be imported and used by other TE modules.  When
   imported and used, the resultant schema will have data nodes that can
   be writable or readable.  Access to such 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.

   The security considerations spelled out in the YANG 1.1 specification
   [RFC7950] apply for this document as well.

8.  References

8.1.  Normative References

   [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>.

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

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [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>.

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [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>.

   [RFC8294]  Liu, X., Qu, Y., Lindem, A., Hopps, C., and L. Berger,
              "Common YANG Data Types for the Routing Area", RFC 8294,
              DOI 10.17487/RFC8294, December 2017,
              <https://www.rfc-editor.org/info/rfc8294>.

   [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>.

   [RFC8345]  Clemm, A., Medved, J., Varga, R., Bahadur, N.,
              Ananthakrishnan, H., and X. Liu, "A YANG Data Model for
              Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March
              2018, <https://www.rfc-editor.org/info/rfc8345>.

   [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>.

8.2.  Informative References

   [G.709]    ITU-T, "Interfaces for the optical transport network",
              ITU-T Recommendation G.709, June 2016,
              <https://www.itu.int/rec/T-REC-G.709/>.

   [RFC2702]  Awduche, D., Malcolm, J., Agogbua, J., O'Dell, M., and J.
              McManus, "Requirements for Traffic Engineering Over MPLS",
              RFC 2702, DOI 10.17487/RFC2702, September 1999,
              <https://www.rfc-editor.org/info/rfc2702>.

   [RFC3209]  Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
              and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
              Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
              <https://www.rfc-editor.org/info/rfc3209>.

   [RFC3272]  Awduche, D., Chiu, A., Elwalid, A., Widjaja, I., and X.
              Xiao, "Overview and Principles of Internet Traffic
              Engineering", RFC 3272, DOI 10.17487/RFC3272, May 2002,
              <https://www.rfc-editor.org/info/rfc3272>.

   [RFC3471]  Berger, L., Ed., "Generalized Multi-Protocol Label
              Switching (GMPLS) Signaling Functional Description",
              RFC 3471, DOI 10.17487/RFC3471, January 2003,
              <https://www.rfc-editor.org/info/rfc3471>.

   [RFC3477]  Kompella, K. and Y. Rekhter, "Signalling Unnumbered Links
              in Resource ReSerVation Protocol - Traffic Engineering
              (RSVP-TE)", RFC 3477, DOI 10.17487/RFC3477, January 2003,
              <https://www.rfc-editor.org/info/rfc3477>.

   [RFC3630]  Katz, D., Kompella, K., and D. Yeung, "Traffic Engineering
              (TE) Extensions to OSPF Version 2", RFC 3630,
              DOI 10.17487/RFC3630, September 2003,
              <https://www.rfc-editor.org/info/rfc3630>.

   [RFC3785]  Le Faucheur, F., Uppili, R., Vedrenne, A., Merckx, P., and
              T. Telkamp, "Use of Interior Gateway Protocol (IGP) Metric
              as a second MPLS Traffic Engineering (TE) Metric", BCP 87,
              RFC 3785, DOI 10.17487/RFC3785, May 2004,
              <https://www.rfc-editor.org/info/rfc3785>.

   [RFC4090]  Pan, P., Ed., Swallow, G., Ed., and A. Atlas, Ed., "Fast
              Reroute Extensions to RSVP-TE for LSP Tunnels", RFC 4090,
              DOI 10.17487/RFC4090, May 2005,
              <https://www.rfc-editor.org/info/rfc4090>.

   [RFC4124]  Le Faucheur, F., Ed., "Protocol Extensions for Support of
              Diffserv-aware MPLS Traffic Engineering", RFC 4124,
              DOI 10.17487/RFC4124, June 2005,
              <https://www.rfc-editor.org/info/rfc4124>.

   [RFC4125]  Le Faucheur, F. and W. Lai, "Maximum Allocation Bandwidth
              Constraints Model for Diffserv-aware MPLS Traffic
              Engineering", RFC 4125, DOI 10.17487/RFC4125, June 2005,
              <https://www.rfc-editor.org/info/rfc4125>.

   [RFC4126]  Ash, J., "Max Allocation with Reservation Bandwidth
              Constraints Model for Diffserv-aware MPLS Traffic
              Engineering & Performance Comparisons", RFC 4126,
              DOI 10.17487/RFC4126, June 2005,
              <https://www.rfc-editor.org/info/rfc4126>.

   [RFC4127]  Le Faucheur, F., Ed., "Russian Dolls Bandwidth Constraints
              Model for Diffserv-aware MPLS Traffic Engineering",
              RFC 4127, DOI 10.17487/RFC4127, June 2005,
              <https://www.rfc-editor.org/info/rfc4127>.

   [RFC4202]  Kompella, K., Ed. and Y. Rekhter, Ed., "Routing Extensions
              in Support of Generalized Multi-Protocol Label Switching
              (GMPLS)", RFC 4202, DOI 10.17487/RFC4202, October 2005,
              <https://www.rfc-editor.org/info/rfc4202>.

   [RFC4203]  Kompella, K., Ed. and Y. Rekhter, Ed., "OSPF Extensions in
              Support of Generalized Multi-Protocol Label Switching
              (GMPLS)", RFC 4203, DOI 10.17487/RFC4203, October 2005,
              <https://www.rfc-editor.org/info/rfc4203>.

   [RFC4328]  Papadimitriou, D., Ed., "Generalized Multi-Protocol Label
              Switching (GMPLS) Signaling Extensions for G.709 Optical
              Transport Networks Control", RFC 4328,
              DOI 10.17487/RFC4328, January 2006,
              <https://www.rfc-editor.org/info/rfc4328>.

   [RFC4427]  Mannie, E., Ed. and D. Papadimitriou, Ed., "Recovery
              (Protection and Restoration) Terminology for Generalized
              Multi-Protocol Label Switching (GMPLS)", RFC 4427,
              DOI 10.17487/RFC4427, March 2006,
              <https://www.rfc-editor.org/info/rfc4427>.

   [RFC4561]  Vasseur, J.-P., Ed., Ali, Z., and S. Sivabalan,
              "Definition of a Record Route Object (RRO) Node-Id Sub-
              Object", RFC 4561, DOI 10.17487/RFC4561, June 2006,
              <https://www.rfc-editor.org/info/rfc4561>.

   [RFC4657]  Ash, J., Ed. and J.L. Le Roux, Ed., "Path Computation
              Element (PCE) Communication Protocol Generic
              Requirements", RFC 4657, DOI 10.17487/RFC4657, September
              2006, <https://www.rfc-editor.org/info/rfc4657>.

   [RFC4736]  Vasseur, JP., Ed., Ikejiri, Y., and R. Zhang,
              "Reoptimization of Multiprotocol Label Switching (MPLS)
              Traffic Engineering (TE) Loosely Routed Label Switched
              Path (LSP)", RFC 4736, DOI 10.17487/RFC4736, November
              2006, <https://www.rfc-editor.org/info/rfc4736>.

   [RFC4872]  Lang, J.P., Ed., Rekhter, Y., Ed., and D. Papadimitriou,
              Ed., "RSVP-TE Extensions in Support of End-to-End
              Generalized Multi-Protocol Label Switching (GMPLS)
              Recovery", RFC 4872, DOI 10.17487/RFC4872, May 2007,
              <https://www.rfc-editor.org/info/rfc4872>.

   [RFC4873]  Berger, L., Bryskin, I., Papadimitriou, D., and A. Farrel,
              "GMPLS Segment Recovery", RFC 4873, DOI 10.17487/RFC4873,
              May 2007, <https://www.rfc-editor.org/info/rfc4873>.

   [RFC4875]  Aggarwal, R., Ed., Papadimitriou, D., Ed., and S.
              Yasukawa, Ed., "Extensions to Resource Reservation
              Protocol - Traffic Engineering (RSVP-TE) for Point-to-
              Multipoint TE Label Switched Paths (LSPs)", RFC 4875,
              DOI 10.17487/RFC4875, May 2007,
              <https://www.rfc-editor.org/info/rfc4875>.

   [RFC4920]  Farrel, A., Ed., Satyanarayana, A., Iwata, A., Fujita, N.,
              and G. Ash, "Crankback Signaling Extensions for MPLS and
              GMPLS RSVP-TE", RFC 4920, DOI 10.17487/RFC4920, July 2007,
              <https://www.rfc-editor.org/info/rfc4920>.

   [RFC5003]  Metz, C., Martini, L., Balus, F., and J. Sugimoto,
              "Attachment Individual Identifier (AII) Types for
              Aggregation", RFC 5003, DOI 10.17487/RFC5003, September
              2007, <https://www.rfc-editor.org/info/rfc5003>.

   [RFC5150]  Ayyangar, A., Kompella, K., Vasseur, JP., and A. Farrel,
              "Label Switched Path Stitching with Generalized
              Multiprotocol Label Switching Traffic Engineering (GMPLS
              TE)", RFC 5150, DOI 10.17487/RFC5150, February 2008,
              <https://www.rfc-editor.org/info/rfc5150>.

   [RFC5151]  Farrel, A., Ed., Ayyangar, A., and JP. Vasseur, "Inter-
              Domain MPLS and GMPLS Traffic Engineering -- Resource
              Reservation Protocol-Traffic Engineering (RSVP-TE)
              Extensions", RFC 5151, DOI 10.17487/RFC5151, February
              2008, <https://www.rfc-editor.org/info/rfc5151>.

   [RFC5305]  Li, T. and H. Smit, "IS-IS Extensions for Traffic
              Engineering", RFC 5305, DOI 10.17487/RFC5305, October
              2008, <https://www.rfc-editor.org/info/rfc5305>.

   [RFC5307]  Kompella, K., Ed. and Y. Rekhter, Ed., "IS-IS Extensions
              in Support of Generalized Multi-Protocol Label Switching
              (GMPLS)", RFC 5307, DOI 10.17487/RFC5307, October 2008,
              <https://www.rfc-editor.org/info/rfc5307>.

   [RFC5420]  Farrel, A., Ed., Papadimitriou, D., Vasseur, JP., and A.
              Ayyangar, "Encoding of Attributes for MPLS LSP
              Establishment Using Resource Reservation Protocol Traffic
              Engineering (RSVP-TE)", RFC 5420, DOI 10.17487/RFC5420,
              February 2009, <https://www.rfc-editor.org/info/rfc5420>.

   [RFC5541]  Le Roux, JL., Vasseur, JP., and Y. Lee, "Encoding of
              Objective Functions in the Path Computation Element
              Communication Protocol (PCEP)", RFC 5541,
              DOI 10.17487/RFC5541, June 2009,
              <https://www.rfc-editor.org/info/rfc5541>.

   [RFC5712]  Meyer, M., Ed. and JP. Vasseur, Ed., "MPLS Traffic
              Engineering Soft Preemption", RFC 5712,
              DOI 10.17487/RFC5712, January 2010,
              <https://www.rfc-editor.org/info/rfc5712>.

   [RFC5817]  Ali, Z., Vasseur, JP., Zamfir, A., and J. Newton,
              "Graceful Shutdown in MPLS and Generalized MPLS Traffic
              Engineering Networks", RFC 5817, DOI 10.17487/RFC5817,
              April 2010, <https://www.rfc-editor.org/info/rfc5817>.

   [RFC6001]  Papadimitriou, D., Vigoureux, M., Shiomoto, K., Brungard,
              D., and JL. Le Roux, "Generalized MPLS (GMPLS) Protocol
              Extensions for Multi-Layer and Multi-Region Networks (MLN/
              MRN)", RFC 6001, DOI 10.17487/RFC6001, October 2010,
              <https://www.rfc-editor.org/info/rfc6001>.

   [RFC6004]  Berger, L. and D. Fedyk, "Generalized MPLS (GMPLS) Support
              for Metro Ethernet Forum and G.8011 Ethernet Service
              Switching", RFC 6004, DOI 10.17487/RFC6004, October 2010,
              <https://www.rfc-editor.org/info/rfc6004>.

   [RFC6119]  Harrison, J., Berger, J., and M. Bartlett, "IPv6 Traffic
              Engineering in IS-IS", RFC 6119, DOI 10.17487/RFC6119,
              February 2011, <https://www.rfc-editor.org/info/rfc6119>.

   [RFC6370]  Bocci, M., Swallow, G., and E. Gray, "MPLS Transport
              Profile (MPLS-TP) Identifiers", RFC 6370,
              DOI 10.17487/RFC6370, September 2011,
              <https://www.rfc-editor.org/info/rfc6370>.

   [RFC6378]  Weingarten, Y., Ed., Bryant, S., Osborne, E., Sprecher,
              N., and A. Fulignoli, Ed., "MPLS Transport Profile (MPLS-
              TP) Linear Protection", RFC 6378, DOI 10.17487/RFC6378,
              October 2011, <https://www.rfc-editor.org/info/rfc6378>.

   [RFC6511]  Ali, Z., Swallow, G., and R. Aggarwal, "Non-Penultimate
              Hop Popping Behavior and Out-of-Band Mapping for RSVP-TE
              Label Switched Paths", RFC 6511, DOI 10.17487/RFC6511,
              February 2012, <https://www.rfc-editor.org/info/rfc6511>.

   [RFC6780]  Berger, L., Le Faucheur, F., and A. Narayanan, "RSVP
              ASSOCIATION Object Extensions", RFC 6780,
              DOI 10.17487/RFC6780, October 2012,
              <https://www.rfc-editor.org/info/rfc6780>.

   [RFC6790]  Kompella, K., Drake, J., Amante, S., Henderickx, W., and
              L. Yong, "The Use of Entropy Labels in MPLS Forwarding",
              RFC 6790, DOI 10.17487/RFC6790, November 2012,
              <https://www.rfc-editor.org/info/rfc6790>.

   [RFC6827]  Malis, A., Ed., Lindem, A., Ed., and D. Papadimitriou,
              Ed., "Automatically Switched Optical Network (ASON)
              Routing for OSPFv2 Protocols", RFC 6827,
              DOI 10.17487/RFC6827, January 2013,
              <https://www.rfc-editor.org/info/rfc6827>.

   [RFC7139]  Zhang, F., Ed., Zhang, G., Belotti, S., Ceccarelli, D.,
              and K. Pithewan, "GMPLS Signaling Extensions for Control
              of Evolving G.709 Optical Transport Networks", RFC 7139,
              DOI 10.17487/RFC7139, March 2014,
              <https://www.rfc-editor.org/info/rfc7139>.

   [RFC7260]  Takacs, A., Fedyk, D., and J. He, "GMPLS RSVP-TE
              Extensions for Operations, Administration, and Maintenance
              (OAM) Configuration", RFC 7260, DOI 10.17487/RFC7260, June
              2014, <https://www.rfc-editor.org/info/rfc7260>.

   [RFC7308]  Osborne, E., "Extended Administrative Groups in MPLS
              Traffic Engineering (MPLS-TE)", RFC 7308,
              DOI 10.17487/RFC7308, July 2014,
              <https://www.rfc-editor.org/info/rfc7308>.

   [RFC7471]  Giacalone, S., Ward, D., Drake, J., Atlas, A., and S.
              Previdi, "OSPF Traffic Engineering (TE) Metric
              Extensions", RFC 7471, DOI 10.17487/RFC7471, March 2015,
              <https://www.rfc-editor.org/info/rfc7471>.

   [RFC7551]  Zhang, F., Ed., Jing, R., and R. Gandhi, Ed., "RSVP-TE
              Extensions for Associated Bidirectional Label Switched
              Paths (LSPs)", RFC 7551, DOI 10.17487/RFC7551, May 2015,
              <https://www.rfc-editor.org/info/rfc7551>.

   [RFC7570]  Margaria, C., Ed., Martinelli, G., Balls, S., and B.
              Wright, "Label Switched Path (LSP) Attribute in the
              Explicit Route Object (ERO)", RFC 7570,
              DOI 10.17487/RFC7570, July 2015,
              <https://www.rfc-editor.org/info/rfc7570>.

   [RFC7571]  Dong, J., Chen, M., Li, Z., and D. Ceccarelli, "GMPLS
              RSVP-TE Extensions for Lock Instruct and Loopback",
              RFC 7571, DOI 10.17487/RFC7571, July 2015,
              <https://www.rfc-editor.org/info/rfc7571>.

   [RFC7579]  Bernstein, G., Ed., Lee, Y., Ed., Li, D., Imajuku, W., and
              J. Han, "General Network Element Constraint Encoding for
              GMPLS-Controlled Networks", RFC 7579,
              DOI 10.17487/RFC7579, June 2015,
              <https://www.rfc-editor.org/info/rfc7579>.

   [RFC7823]  Atlas, A., Drake, J., Giacalone, S., and S. Previdi,
              "Performance-Based Path Selection for Explicitly Routed
              Label Switched Paths (LSPs) Using TE Metric Extensions",
              RFC 7823, DOI 10.17487/RFC7823, May 2016,
              <https://www.rfc-editor.org/info/rfc7823>.

   [RFC8001]  Zhang, F., Ed., Gonzalez de Dios, O., Ed., Margaria, C.,
              Hartley, M., and Z. Ali, "RSVP-TE Extensions for
              Collecting Shared Risk Link Group (SRLG) Information",
              RFC 8001, DOI 10.17487/RFC8001, January 2017,
              <https://www.rfc-editor.org/info/rfc8001>.

   [RFC8149]  Saad, T., Ed., Gandhi, R., Ed., Ali, Z., Venator, R., and
              Y. Kamite, "RSVP Extensions for Reoptimization of Loosely
              Routed Point-to-Multipoint Traffic Engineering Label
              Switched Paths (LSPs)", RFC 8149, DOI 10.17487/RFC8149,
              April 2017, <https://www.rfc-editor.org/info/rfc8149>.

   [RFC8169]  Mirsky, G., Ruffini, S., Gray, E., Drake, J., Bryant, S.,
              and A. Vainshtein, "Residence Time Measurement in MPLS
              Networks", RFC 8169, DOI 10.17487/RFC8169, May 2017,
              <https://www.rfc-editor.org/info/rfc8169>.

   [RFC8570]  Ginsberg, L., Ed., Previdi, S., Ed., Giacalone, S., Ward,
              D., Drake, J., and Q. Wu, "IS-IS Traffic Engineering (TE)
              Metric Extensions", RFC 8570, DOI 10.17487/RFC8570, March
              2019, <https://www.rfc-editor.org/info/rfc8570>.

Acknowledgments

   The authors would like to thank the members of the multi-vendor YANG
   design team who are involved in the definition of these data types.

   The authors would also like to thank Tom Petch, Jan Lindblad, Sergio
   Belotti, Italo Busi, Carlo Perocchio, Francesco Lazzeri, and Aihua
   Guo for their review comments and for providing valuable feedback on
   this document.

Contributors

   Himanshu Shah
   Ciena

   Email: hshah@ciena.com


   Young Lee
   Samsung Electronics

   Email: younglee.tx@gmail.com


Authors' Addresses

   Tarek Saad
   Juniper Networks

   Email: tsaad@juniper.net


   Rakesh Gandhi
   Cisco Systems, Inc.

   Email: rgandhi@cisco.com


   Xufeng Liu
   Volta Networks

   Email: xufeng.liu.ietf@gmail.com


   Vishnu Pavan Beeram
   Juniper Networks

   Email: vbeeram@juniper.net


   Igor Bryskin
   Futurewei Technologies, Inc.

   Email: i_bryskin@yahoo.com
