ietf-routing-types.yang

module ietf-routing-types {
  namespace "urn:ietf:params:xml:ns:yang:ietf-routing-types";
  prefix rt-types;

  import ietf-yang-types {
    prefix yang;
  }
  import ietf-inet-types {
    prefix inet;
  }

  organization
    "IETF RTGWG - Routing Area Working Group";
  contact
    "WG Web:   <https://datatracker.ietf.org/wg/rtgwg/>
     WG List:  <mailto:rtgwg@ietf.org>

     Editors:  Xufeng Liu
               <mailto:Xufeng_Liu@jabail.com>
               Yingzhen Qu
               <mailto:yingzhen.qu@huawei.com>
               Acee Lindem
               <mailto:acee@cisco.com>
               Christian Hopps
               <mailto:chopps@chopps.org>
               Lou Berger
               <mailto:lberger@labn.com>";

  description
    "This module contains a collection of YANG data types
     considered generally useful for routing protocols.

     Copyright (c) 2017 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 8294; see
     the RFC itself for full legal notices.";

   revision 2017-12-04 {
     description "Initial revision.";
     reference
       "RFC 8294: Common YANG Data Types for the Routing Area.
        Section 3.";
  }

  /*** Identities related to MPLS/GMPLS ***/

  identity mpls-label-special-purpose-value {
    description
      "Base identity for deriving identities describing
       special-purpose Multiprotocol Label Switching (MPLS) label
       values.";
    reference
      "RFC 7274: Allocating and Retiring Special-Purpose MPLS
       Labels.";
  }

  identity ipv4-explicit-null-label {
    base mpls-label-special-purpose-value;
    description
      "This identity represents the IPv4 Explicit NULL Label.";
    reference
      "RFC 3032: MPLS Label Stack Encoding.  Section 2.1.";
  }

  identity router-alert-label {
    base mpls-label-special-purpose-value;
    description
      "This identity represents the Router Alert Label.";
    reference
      "RFC 3032: MPLS Label Stack Encoding.  Section 2.1.";
  }

  identity ipv6-explicit-null-label {
    base mpls-label-special-purpose-value;
    description
      "This identity represents the IPv6 Explicit NULL Label.";
    reference
      "RFC 3032: MPLS Label Stack Encoding.  Section 2.1.";
  }

  identity implicit-null-label {
    base mpls-label-special-purpose-value;
    description
      "This identity represents the Implicit NULL Label.";
    reference
      "RFC 3032: MPLS Label Stack Encoding.  Section 2.1.";
  }

  identity entropy-label-indicator {
    base mpls-label-special-purpose-value;
    description
      "This identity represents the Entropy Label Indicator.";
    reference
      "RFC 6790: The Use of Entropy Labels in MPLS Forwarding.
       Sections 3 and 10.1.";
  }

  identity gal-label {
    base mpls-label-special-purpose-value;
    description
      "This identity represents the Generic Associated Channel
       (G-ACh) Label (GAL).";
    reference
      "RFC 5586: MPLS Generic Associated Channel.
       Sections 4 and 10.";
  }

  identity oam-alert-label {
    base mpls-label-special-purpose-value;
    description
      "This identity represents the OAM Alert Label.";
    reference
      "RFC 3429: Assignment of the 'OAM Alert Label' for
       Multiprotocol Label Switching Architecture (MPLS)
       Operation and Maintenance (OAM) Functions.
       Sections 3 and 6.";
  }

  identity extension-label {
    base mpls-label-special-purpose-value;
    description
      "This identity represents the Extension Label.";
    reference
      "RFC 7274: Allocating and Retiring Special-Purpose MPLS
       Labels.  Sections 3.1 and 5.";
  }

  /*** Collection of types related to routing ***/

  typedef router-id {
    type yang:dotted-quad;
    description
      "A 32-bit number in the dotted-quad format assigned to each
       router.  This number uniquely identifies the router within
       an Autonomous System.";
  }

  /*** Collection of types related to VPNs ***/

  typedef route-target {
    type string {
      pattern
        '(0:(6553[0-5]|655[0-2][0-9]|65[0-4][0-9]{2}|'
      +     '6[0-4][0-9]{3}|'
      +     '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0):(429496729[0-5]|'
      +     '42949672[0-8][0-9]|'
      +     '4294967[01][0-9]{2}|429496[0-6][0-9]{3}|'
      +     '42949[0-5][0-9]{4}|'
      +     '4294[0-8][0-9]{5}|429[0-3][0-9]{6}|'
      +     '42[0-8][0-9]{7}|4[01][0-9]{8}|'
      +     '[1-3][0-9]{9}|[1-9][0-9]{0,8}|0))|'
      + '(1:((([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|'
      +     '25[0-5])\.){3}([0-9]|[1-9][0-9]|'
      +     '1[0-9]{2}|2[0-4][0-9]|25[0-5])):(6553[0-5]|'
      +     '655[0-2][0-9]|'
      +     '65[0-4][0-9]{2}|6[0-4][0-9]{3}|'
      +     '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0))|'
      + '(2:(429496729[0-5]|42949672[0-8][0-9]|'
      +     '4294967[01][0-9]{2}|'
      +     '429496[0-6][0-9]{3}|42949[0-5][0-9]{4}|'
      +     '4294[0-8][0-9]{5}|'
      +     '429[0-3][0-9]{6}|42[0-8][0-9]{7}|4[01][0-9]{8}|'
      +     '[1-3][0-9]{9}|[1-9][0-9]{0,8}|0):'
      +     '(6553[0-5]|655[0-2][0-9]|65[0-4][0-9]{2}|'
      +     '6[0-4][0-9]{3}|'
      +     '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0))|'
      + '(6(:[a-fA-F0-9]{2}){6})|'
      + '(([3-57-9a-fA-F]|[1-9a-fA-F][0-9a-fA-F]{1,3}):'
      +     '[0-9a-fA-F]{1,12})';
    }

    description
      "A Route Target is an 8-octet BGP extended community
       initially identifying a set of sites in a BGP VPN
       (RFC 4364).  However, it has since taken on a more general
       role in BGP route filtering.  A Route Target consists of two
       or three fields: a 2-octet Type field, an administrator
       field, and, optionally, an assigned number field.

       According to the data formats for types 0, 1, 2, and 6 as
       defined in RFC 4360, RFC 5668, and RFC 7432, the encoding
       pattern is defined as:

       0:2-octet-asn:4-octet-number
       1:4-octet-ipv4addr:2-octet-number
       2:4-octet-asn:2-octet-number
       6:6-octet-mac-address

       Additionally, a generic pattern is defined for future
       Route Target types:

       2-octet-other-hex-number:6-octet-hex-number

       Some valid examples are 0:100:100, 1:1.1.1.1:100,
       2:1234567890:203, and 6:26:00:08:92:78:00.";
    reference
      "RFC 4360: BGP Extended Communities Attribute.
       RFC 4364: BGP/MPLS IP Virtual Private Networks (VPNs).
       RFC 5668: 4-Octet AS Specific BGP Extended Community.
       RFC 7432: BGP MPLS-Based Ethernet VPN.";
  }

  typedef ipv6-route-target {
    type string {
      pattern
          '((:|[0-9a-fA-F]{0,4}):)([0-9a-fA-F]{0,4}:){0,5}'
          + '((([0-9a-fA-F]{0,4}:)?(:|[0-9a-fA-F]{0,4}))|'
          + '(((25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9]?[0-9])\.){3}'
          + '(25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9]?[0-9])))'
          + ':'
          + '(6553[0-5]|655[0-2][0-9]|65[0-4][0-9]{2}|'
          + '6[0-4][0-9]{3}|'
          + '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0)';
      pattern '((([^:]+:){6}(([^:]+:[^:]+)|(.*\..*)))|'
          + '((([^:]+:)*[^:]+)?::(([^:]+:)*[^:]+)?))'
          + ':'
          + '(6553[0-5]|655[0-2][0-9]|65[0-4][0-9]{2}|'
          + '6[0-4][0-9]{3}|'
          + '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0)';
    }
    description
      "An IPv6 Route Target is a 20-octet BGP IPv6 Address
       Specific Extended Community serving the same function
       as a standard 8-octet Route Target, except that it only
       allows an IPv6 address as the global administrator.
       The format is <ipv6-address:2-octet-number>.

       Two valid examples are 2001:db8::1:6544 and
       2001:db8::5eb1:791:6b37:17958.";
    reference
      "RFC 5701: IPv6 Address Specific BGP Extended Community
       Attribute.";
  }

  typedef route-target-type {
    type enumeration {
      enum import {
        value 0;
        description
          "The Route Target applies to route import.";
      }
      enum export {
        value 1;
        description
          "The Route Target applies to route export.";
      }

      enum both {
        value 2;
        description
          "The Route Target applies to both route import and
           route export.";
      }
    }
    description
      "Indicates the role a Route Target takes in route filtering.";
    reference
      "RFC 4364: BGP/MPLS IP Virtual Private Networks (VPNs).";
  }

  typedef route-distinguisher {
    type string {
      pattern
        '(0:(6553[0-5]|655[0-2][0-9]|65[0-4][0-9]{2}|'
      +     '6[0-4][0-9]{3}|'
      +     '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0):(429496729[0-5]|'
      +     '42949672[0-8][0-9]|'
      +     '4294967[01][0-9]{2}|429496[0-6][0-9]{3}|'
      +     '42949[0-5][0-9]{4}|'
      +     '4294[0-8][0-9]{5}|429[0-3][0-9]{6}|'
      +     '42[0-8][0-9]{7}|4[01][0-9]{8}|'
      +     '[1-3][0-9]{9}|[1-9][0-9]{0,8}|0))|'
      + '(1:((([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|'
      +     '25[0-5])\.){3}([0-9]|[1-9][0-9]|'
      +     '1[0-9]{2}|2[0-4][0-9]|25[0-5])):(6553[0-5]|'
      +     '655[0-2][0-9]|'
      +     '65[0-4][0-9]{2}|6[0-4][0-9]{3}|'
      +     '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0))|'
      + '(2:(429496729[0-5]|42949672[0-8][0-9]|'
      +     '4294967[01][0-9]{2}|'
      +     '429496[0-6][0-9]{3}|42949[0-5][0-9]{4}|'
      +     '4294[0-8][0-9]{5}|'
      +     '429[0-3][0-9]{6}|42[0-8][0-9]{7}|4[01][0-9]{8}|'
      +     '[1-3][0-9]{9}|[1-9][0-9]{0,8}|0):'
      +     '(6553[0-5]|655[0-2][0-9]|65[0-4][0-9]{2}|'
      +     '6[0-4][0-9]{3}|'
      +     '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0))|'
      + '(6(:[a-fA-F0-9]{2}){6})|'
      + '(([3-57-9a-fA-F]|[1-9a-fA-F][0-9a-fA-F]{1,3}):'
      +     '[0-9a-fA-F]{1,12})';
    }

    description
      "A Route Distinguisher is an 8-octet value used to
       distinguish routes from different BGP VPNs (RFC 4364).
       A Route Distinguisher will have the same format as a
       Route Target as per RFC 4360 and will consist of
       two or three fields: a 2-octet Type field, an administrator
       field, and, optionally, an assigned number field.

       According to the data formats for types 0, 1, 2, and 6 as
       defined in RFC 4360, RFC 5668, and RFC 7432, the encoding
       pattern is defined as:

       0:2-octet-asn:4-octet-number
       1:4-octet-ipv4addr:2-octet-number
       2:4-octet-asn:2-octet-number
       6:6-octet-mac-address

       Additionally, a generic pattern is defined for future
       route discriminator types:

       2-octet-other-hex-number:6-octet-hex-number

       Some valid examples are 0:100:100, 1:1.1.1.1:100,
       2:1234567890:203, and 6:26:00:08:92:78:00.";
    reference
      "RFC 4360: BGP Extended Communities Attribute.
       RFC 4364: BGP/MPLS IP Virtual Private Networks (VPNs).
       RFC 5668: 4-Octet AS Specific BGP Extended Community.
       RFC 7432: BGP MPLS-Based Ethernet VPN.";
  }

  typedef route-origin {
    type string {
      pattern
        '(0:(6553[0-5]|655[0-2][0-9]|65[0-4][0-9]{2}|'
      +     '6[0-4][0-9]{3}|'
      +     '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0):(429496729[0-5]|'
      +     '42949672[0-8][0-9]|'
      +     '4294967[01][0-9]{2}|429496[0-6][0-9]{3}|'
      +     '42949[0-5][0-9]{4}|'
      +     '4294[0-8][0-9]{5}|429[0-3][0-9]{6}|'
      +     '42[0-8][0-9]{7}|4[01][0-9]{8}|'
      +     '[1-3][0-9]{9}|[1-9][0-9]{0,8}|0))|'
      + '(1:((([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|'
      +     '25[0-5])\.){3}([0-9]|[1-9][0-9]|'
      +     '1[0-9]{2}|2[0-4][0-9]|25[0-5])):(6553[0-5]|'
      +     '655[0-2][0-9]|'
      +     '65[0-4][0-9]{2}|6[0-4][0-9]{3}|'
      +     '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0))|'
      + '(2:(429496729[0-5]|42949672[0-8][0-9]|'
      +     '4294967[01][0-9]{2}|'
      +     '429496[0-6][0-9]{3}|42949[0-5][0-9]{4}|'
      +     '4294[0-8][0-9]{5}|'
      +     '429[0-3][0-9]{6}|42[0-8][0-9]{7}|4[01][0-9]{8}|'
      +     '[1-3][0-9]{9}|[1-9][0-9]{0,8}|0):'
      +     '(6553[0-5]|655[0-2][0-9]|65[0-4][0-9]{2}|'
      +     '6[0-4][0-9]{3}|'
      +     '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0))|'
      + '(6(:[a-fA-F0-9]{2}){6})|'
      + '(([3-57-9a-fA-F]|[1-9a-fA-F][0-9a-fA-F]{1,3}):'
      +    '[0-9a-fA-F]{1,12})';
    }
    description
      "A Route Origin is an 8-octet BGP extended community
       identifying the set of sites where the BGP route
       originated (RFC 4364).  A Route Origin will have the same
       format as a Route Target as per RFC 4360 and will consist
       of two or three fields: a 2-octet Type field, an
       administrator field, and, optionally, an assigned number
       field.

       According to the data formats for types 0, 1, 2, and 6 as
       defined in RFC 4360, RFC 5668, and RFC 7432, the encoding
       pattern is defined as:

       0:2-octet-asn:4-octet-number
       1:4-octet-ipv4addr:2-octet-number
       2:4-octet-asn:2-octet-number
       6:6-octet-mac-address
       Additionally, a generic pattern is defined for future
       Route Origin types:

       2-octet-other-hex-number:6-octet-hex-number

       Some valid examples are 0:100:100, 1:1.1.1.1:100,
       2:1234567890:203, and 6:26:00:08:92:78:00.";
    reference
      "RFC 4360: BGP Extended Communities Attribute.
       RFC 4364: BGP/MPLS IP Virtual Private Networks (VPNs).
       RFC 5668: 4-Octet AS Specific BGP Extended Community.
       RFC 7432: BGP MPLS-Based Ethernet VPN.";
  }

  typedef ipv6-route-origin {
    type string {
      pattern
          '((:|[0-9a-fA-F]{0,4}):)([0-9a-fA-F]{0,4}:){0,5}'
          + '((([0-9a-fA-F]{0,4}:)?(:|[0-9a-fA-F]{0,4}))|'
          + '(((25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9]?[0-9])\.){3}'
          + '(25[0-5]|2[0-4][0-9]|1[0-9]{2}|[1-9]?[0-9])))'
          + ':'
          + '(6553[0-5]|655[0-2][0-9]|65[0-4][0-9]{2}|'
          + '6[0-4][0-9]{3}|'
          + '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0)';
      pattern '((([^:]+:){6}(([^:]+:[^:]+)|(.*\..*)))|'
          + '((([^:]+:)*[^:]+)?::(([^:]+:)*[^:]+)?))'
          + ':'
          + '(6553[0-5]|655[0-2][0-9]|65[0-4][0-9]{2}|'
          + '6[0-4][0-9]{3}|'
          + '[1-5][0-9]{4}|[1-9][0-9]{0,3}|0)';
    }
    description
      "An IPv6 Route Origin is a 20-octet BGP IPv6 Address
       Specific Extended Community serving the same function
       as a standard 8-octet route, except that it only allows
       an IPv6 address as the global administrator.  The format
       is <ipv6-address:2-octet-number>.

       Two valid examples are 2001:db8::1:6544 and
       2001:db8::5eb1:791:6b37:17958.";
    reference
      "RFC 5701: IPv6 Address Specific BGP Extended Community
       Attribute.";
  }

  /*** Collection of types common to multicast ***/

  typedef ipv4-multicast-group-address {
    type inet:ipv4-address {
      pattern '(2((2[4-9])|(3[0-9]))\.).*';
    }
    description
      "This type represents an IPv4 multicast group address,
       which is in the range of 224.0.0.0 to 239.255.255.255.";
    reference
      "RFC 1112: Host Extensions for IP Multicasting.";
  }

  typedef ipv6-multicast-group-address {
    type inet:ipv6-address {
      pattern '(([fF]{2}[0-9a-fA-F]{2}):).*';
    }
    description
      "This type represents an IPv6 multicast group address,
       which is in the range of ff00::/8.";
    reference
      "RFC 4291: IP Version 6 Addressing Architecture.  Section 2.7.
       RFC 7346: IPv6 Multicast Address Scopes.";
  }

  typedef ip-multicast-group-address {
    type union {
      type ipv4-multicast-group-address;
      type ipv6-multicast-group-address;
    }
    description
      "This type represents a version-neutral IP multicast group
       address.  The format of the textual representation implies
       the IP version.";
  }

  typedef ipv4-multicast-source-address {
    type union {
      type enumeration {
        enum * {
          description
            "Any source address.";
        }
      }
      type inet:ipv4-address;
    }
    description
      "Multicast source IPv4 address type.";
  }

  typedef ipv6-multicast-source-address {
    type union {
      type enumeration {
        enum * {
          description
            "Any source address.";
        }
      }
      type inet:ipv6-address;
    }
    description
      "Multicast source IPv6 address type.";
  }

  /*** Collection of types common to protocols ***/

  typedef bandwidth-ieee-float32 {
    type string {
      pattern
        '0[xX](0((\.0?)?[pP](\+)?0?|(\.0?))|'
      + '1(\.([0-9a-fA-F]{0,5}[02468aAcCeE]?)?)?[pP](\+)?(12[0-7]|'
      + '1[01][0-9]|0?[0-9]?[0-9])?)';
    }
    description
      "Bandwidth in IEEE 754 floating-point 32-bit binary format:
       (-1)**(S) * 2**(Exponent-127) * (1 + Fraction),
       where Exponent uses 8 bits and Fraction uses 23 bits.
       The units are octets per second.
       The encoding format is the external hexadecimal-significant
       character sequences specified in IEEE 754 and ISO/IEC C99.
       The format is restricted to be normalized, non-negative, and
       non-fraction: 0x1.hhhhhhp{+}d, 0X1.HHHHHHP{+}D, or 0x0p0,
       where 'h' and 'H' are hexadecimal digits and 'd' and 'D' are
       integers in the range of [0..127].
       When six hexadecimal digits are used for 'hhhhhh' or
       'HHHHHH', the least significant digit must be an even
       number.  'x' and 'X' indicate hexadecimal; 'p' and 'P'
       indicate a power of two.  Some examples are 0x0p0, 0x1p10,
       and 0x1.abcde2p+20.";
    reference
      "IEEE Std 754-2008: IEEE Standard for Floating-Point
       Arithmetic.
       ISO/IEC C99: Information technology - Programming
       Languages - C.";
  }

  typedef link-access-type {
    type enumeration {
      enum broadcast {
        description
          "Specify broadcast multi-access network.";
      }
      enum non-broadcast-multiaccess {
        description
          "Specify Non-Broadcast Multi-Access (NBMA) network.";
      }
      enum point-to-multipoint {
        description
          "Specify point-to-multipoint network.";
      }
      enum point-to-point {
        description
          "Specify point-to-point network.";
      }
    }
    description
      "Link access type.";
  }

  typedef timer-multiplier {
    type uint8;
    description
      "The number of timer value intervals that should be
       interpreted as a failure.";
  }

  typedef timer-value-seconds16 {
    type union {
      type uint16 {
        range "1..65535";
      }
      type enumeration {
        enum infinity {
          description
            "The timer is set to infinity.";
        }
        enum not-set {
          description
            "The timer is not set.";
        }
      }
    }
    units "seconds";
    description
      "Timer value type, in seconds (16-bit range).";
  }

  typedef timer-value-seconds32 {
    type union {
      type uint32 {
        range "1..4294967295";
      }
      type enumeration {
        enum infinity {
          description
            "The timer is set to infinity.";
        }
        enum not-set {
          description
            "The timer is not set.";
        }
      }
    }
    units "seconds";
    description
      "Timer value type, in seconds (32-bit range).";
  }

  typedef timer-value-milliseconds {
    type union {
      type uint32 {
        range "1..4294967295";
      }
      type enumeration {
        enum infinity {
          description
            "The timer is set to infinity.";
        }
        enum not-set {
          description
            "The timer is not set.";
        }
      }
    }
    units "milliseconds";
    description
      "Timer value type, in milliseconds.";
  }

  typedef percentage {
    type uint8 {
      range "0..100";
    }
    description
      "Integer indicating a percentage value.";
  }

  typedef timeticks64 {
    type uint64;
    description
      "This type is based on the timeticks type defined in
       RFC 6991, but with 64-bit width.  It represents the time,
       modulo 2^64, in hundredths of a second between two epochs.";
    reference
      "RFC 6991: Common YANG Data Types.";
  }

  typedef uint24 {
    type uint32 {
      range "0..16777215";
    }
    description
      "24-bit unsigned integer.";
  }

  /*** Collection of types related to MPLS/GMPLS ***/

  typedef generalized-label {
    type binary;
    description
      "Generalized Label.  Nodes sending and receiving the
       Generalized Label are aware of the link-specific
       label context and type.";
    reference
      "RFC 3471: Generalized Multi-Protocol Label Switching (GMPLS)
       Signaling Functional Description.  Section 3.2.";
  }

  typedef mpls-label-special-purpose {
    type identityref {
      base mpls-label-special-purpose-value;
    }
    description
      "This type represents the special-purpose MPLS label values.";
    reference
      "RFC 3032: MPLS Label Stack Encoding.
       RFC 7274: Allocating and Retiring Special-Purpose MPLS
       Labels.";
  }

  typedef mpls-label-general-use {
    type uint32 {
      range "16..1048575";
    }
    description
      "The 20-bit label value in an MPLS label stack as specified
       in RFC 3032.  This label value does not include the
       encodings of Traffic Class and TTL (Time to Live).
       The label range specified by this type is for general use,
       with special-purpose MPLS label values excluded.";
    reference
      "RFC 3032: MPLS Label Stack Encoding.";
  }

  typedef mpls-label {
    type union {
      type mpls-label-special-purpose;
      type mpls-label-general-use;
    }
    description
      "The 20-bit label value in an MPLS label stack as specified
       in RFC 3032.  This label value does not include the
       encodings of Traffic Class and TTL.";
    reference
      "RFC 3032: MPLS Label Stack Encoding.";
  }

  /*** Groupings **/

  grouping mpls-label-stack {
    description
      "This grouping specifies an MPLS label stack.  The label
       stack is encoded as a list of label stack entries.  The
       list key is an identifier that indicates the relative
       ordering of each entry, with the lowest-value identifier
       corresponding to the top of the label stack.";
    container mpls-label-stack {
      description
        "Container for a list of MPLS label stack entries.";
      list entry {
        key "id";
        description
          "List of MPLS label stack entries.";
        leaf id {
          type uint8;
          description
            "Identifies the entry in a sequence of MPLS label
             stack entries.  An entry with a smaller identifier
             value precedes an entry with a larger identifier
             value in the label stack.  The value of this ID has
             no semantic meaning other than relative ordering
             and referencing the entry.";
        }
        leaf label {
          type rt-types:mpls-label;
          description
            "Label value.";
        }
        leaf ttl {
          type uint8;
          description
            "Time to Live (TTL).";
          reference
            "RFC 3032: MPLS Label Stack Encoding.";
        }
        leaf traffic-class {
          type uint8 {
            range "0..7";
          }
          description
            "Traffic Class (TC).";
          reference
            "RFC 5462: Multiprotocol Label Switching (MPLS) Label
             Stack Entry: 'EXP' Field Renamed to 'Traffic Class'
             Field.";
        }
      }
    }
  }
  grouping vpn-route-targets {
    description
      "A grouping that specifies Route Target import-export rules
       used in BGP-enabled VPNs.";
    reference
      "RFC 4364: BGP/MPLS IP Virtual Private Networks (VPNs).
       RFC 4664: Framework for Layer 2 Virtual Private Networks
       (L2VPNs).";
    list vpn-target {
      key "route-target";
      description
        "List of Route Targets.";
      leaf route-target {
        type rt-types:route-target;
        description
          "Route Target value.";
      }
      leaf route-target-type {
        type rt-types:route-target-type;
        mandatory true;
        description
          "Import/export type of the Route Target.";
      }
    }
  }
}