module ietf-ethernet-segment {
  namespace "urn:ietf:params:xml:ns:yang:ietf-ethernet-segment";
  prefix "es";

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

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

  import ietf-routing-types {
    prefix "rt-types";
  }

  import ietf-interfaces {
    prefix "if";
  }

  import ietf-pseudowires {
    prefix "pw";
  }

  organization  "ietf";
  contact       "ietf";
  description   "ethernet segment";

  revision "2018-02-20" {
    description " - Change the type of attachment circuit to " +
                "   if:interface-ref " +
                "";
    reference   "";
  }

  revision "2017-10-21" {
    description " - Updated ethernet segment's AC/PW members to " +
                "   accommodate more than one AC or more than one " +
                "   PW " +
                " - Added the new preference based DF election " +
                "   method " +
                " - Referenced pseudowires in the new " +
                "   ietf-pseudowires.yang model " +
                " - Moved model to NMDA style specified in " +
                "   draft-dsdt-nmda-guidelines-01.txt " +
                "";
    reference   "";
  }

  revision "2017-03-08" {
    description " - Updated to use BGP parameters from " +
                "   ietf-routing-types.yang instead of from " +
                "   ietf-evpn.yang " +
                " - Updated ethernet segment's AC/PW members to " +
                "   accommodate more than one AC or more than one " +
                "   PW " +
                " - Added the new preference based DF election " +
                "   method " +
                "";
    reference   "";
  }

  revision "2016-07-08" {
    description "   - Added the configuration option to enable or " +
                "     disable per-EVI/EAD route " +
                "   - Added PBB parameter backbone-src-mac " +
                "   - Added operational state branch, initially " +
                "     to match the configuration branch" +
                "";
    reference   "";
  }

  revision "2016-06-23" {
    description "WG document adoption";
    reference   "";
  }

  revision "2015-10-15" {
    description "Initial revision";
    reference   "";
  }

  /* Features */

  feature ethernet-segment-bgp-params {
    description "Ethernet segment's BGP parameters";
  }

  feature ethernet-segment-pbb-params {
    description "Ethernet segment's PBB parameters";
  }

  /* Typedefs */
  typedef status-type {
    type enumeration {
      enum up {
        description "Status is up";
      }
      enum down {
        description "Status is down";
      }
    }
    description "status type";
  }

  typedef df-election-method-type {
    type enumeration {
      enum default {
        value 0;
        description "The default DF election method";
      }
      enum highest-random-weight {
        value 1;
        description "The highest random weight (HRW) method";
        reference "draft-mohanty-bess-evpn-df-election";
      }
      enum preference {
        value 2;
        description "The preference based method";
        reference "draft-rabadan-bess-evpn-pref-df";
      }
    }
    description "The DF election method type";
  }

  /* EVPN Ethernet Segment YANG Model */

  container ethernet-segments {
    description "ethernet-segment";
    list ethernet-segment {
      key "name";
      leaf name {
        type string;
        description "Name of the ethernet segment";
      }
      leaf service-type {
        type string;
        config false;
        description "service-type";
      }
      leaf status {
        type status-type;
        config false;
        description "Ethernet segment status";
      }
      choice ac-or-pw {
        description "ac-or-pw";
        case ac {
          leaf-list ac {
            type if:interface-ref;
            description "Name of attachment circuit";
          }
        }
        case pw {
          leaf-list pw {
            type pw:pseudowire-ref;
            description "Reference to a pseudowire";
          }
        }
      }
      leaf interface-status {
        type status-type;
        config false;
        description "interface status";
      }
      leaf ethernet-segment-identifier {
        type uint32;
        description "Ethernet segment identifier (esi)";
      }
      choice active-mode {
        mandatory true;
        description "Choice of active mode";
        case single-active {
          leaf single-active-mode {
            type empty;
            description "single-active-mode";
          }
        }
        case all-active {
          leaf all-active-mode {
            type empty;
            description "all-active-mode";
          }
        }
      }
      container pbb-parameters {
        if-feature ethernet-segment-pbb-params;
        description "PBB configuration";
        leaf backbone-src-mac {
          type yang:mac-address;
          description "backbone-src-mac, only if this is a PBB";
        }
      }
      container bgp-parameters {
        description "BGP parameters";
        container common {
          description "BGP parameters common to all pseudowires";
          list rd-rt {
            if-feature ethernet-segment-bgp-params;
            key "route-distinguisher";
            leaf route-distinguisher {
              type rt-types:route-distinguisher;
              description "Route distinguisher";
            }
            uses rt-types:vpn-route-targets;
            description "A list of route distinguishers and " +
                        "corresponding VPN route targets";
          }
        }
      }
      container df-election {
        description "df-election";
        leaf df-election-method {
          type df-election-method-type;
          description "The DF election method";
        }
        leaf preference {
          when "../df-election-method = 'preference'" {
            description "The preference value is only applicable " +
                        "to the preference based method";
          }
          type uint16;
          description "The DF preference";
        }
        leaf revertive {
          when "../df-election-method = 'preference'" {
            description "The revertive value is only applicable " +
                        "to the preference method";
          }
          type boolean;
          default true;
          description "The 'preempt' or 'revertive' behavior";
        }
        leaf election-wait-time {
          type uint32;
          description "election-wait-time";
        }
      }
      leaf ead-evi-route {
        type boolean;
        default false;
        description "Enable (true) or disable (false) ead-evi-route";
      }
      leaf esi-label {
        type string;
        config false;
        description "esi-label";
      }
      list member {
        config false;
        leaf ip-address {
          type inet:ip-address;
          description "ip-address";
        }
        description "member of the ethernet segment";
      }
      list df {
        config false;
        leaf service-identifier {
          type uint32;
          description "service-identifier";
        }
        leaf vlan {
          type uint32;
          description "vlan";
        }
        leaf ip-address {
          type inet:ip-address;
          description "ip-address";
        }
        description "df of an evpn instance's vlan";
      }
      description "An ethernet segment";
    }
  }
}