module openconfig-mpls-ldp {

  yang-version "1";

  // namespace
  namespace "http://openconfig.net/yang/ldp";

  prefix "oc-ldp";

  // import some basic types
  import openconfig-extensions { prefix oc-ext; }
  import openconfig-inet-types { prefix oc-inet; }
  import openconfig-interfaces { prefix oc-if; }
  import openconfig-yang-types { prefix oc-yang; }
  import openconfig-types { prefix oc-types; }

  // meta
  organization "OpenConfig working group";

  contact
    "OpenConfig working group
    netopenconfig@googlegroups.com";

  description
    "Configuration of Label Distribution Protocol global and LSP-
    specific parameters for IGP-congruent LSPs.

    This model reuses data items defined in the IETF YANG model for
    LDP described by draft-ietf-mpls-ldp-yang-04, YANG Data Model for
    MPLS LDP, following an alternate structure.

    Portions of this code were derived from draft-ietf-mpls-ldp-yang-04.
    Please reproduce this note if possible.

    IETF code is subject to the following copyright and license:
    Copyright (c) IETF Trust and the persons identified as authors of
    the code.
    All rights reserved.

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

  oc-ext:openconfig-version "3.0.0";

  revision "2018-07-02" {
    description
      "Add new RSVP-TE statistics, remove associated-rsvp-session
      leaf. Remove use of date-and-time.";
    reference "3.0.0";
  }

  revision "2018-06-16" {
    description
      "Included attributes for base LDP configuration.";
     reference "2.6.0";
  }

  revision "2018-06-13" {
    description
      "Add ttl-propagation to global MPLS config";
    reference "2.5.0";
  }

  revision "2018-06-05" {
    description
      "Fixed bugs in when statements on RSVP-TE attributes";
    reference "2.4.2";
  }

  revision "2017-08-24" {
    description
      "Minor formatting fixes.";
    reference "2.4.1";
  }

  revision "2017-06-21" {
    description
      "Add TC bits typedef.";
    reference "2.4.0";
  }

  revision "2017-03-22" {
    description
      "Add RSVP calculated-absolute-subscription-bw";
    reference "2.3.0";
  }

  revision "2017-01-26" {
    description
      "Add RSVP Tspec, clarify units for RSVP, remove unused LDP";
    reference "2.2.0";
  }

  revision "2016-12-15" {
    description
      "Add additional MPLS parameters";
    reference "2.1.0";
  }

  revision "2016-09-01" {
    description
      "Revisions based on implementation feedback";
    reference "2.0.0";
  }

  revision "2016-08-08" {
    description
      "Public release of MPLS models";
    reference "1.0.1";
  }

  // typedef statements

  typedef mpls-ldp-adjacency-type {
    type enumeration {
      enum LINK {
        description
          "Link LDP adjacency";
      }
      enum TARGETED {
        description
          "Targeted LDP adjacency";
      }
    }
    description
     "enumerated type for specifying LDP adjacencies";
  }

  typedef mpls-ldp-afi {
    type enumeration {
      enum IPV4 {
        description
          "IPv4 AFI for LDP adjancencies";
      }
      enum IPV6 {
        description
          "IPv6 AFI for LDP adjancencies";
      }
    }
    description
     "enumerated type for specifying LDP AFIs";
  }

  // grouping statements

   grouping ldp-global {
    description
      "Global LDP signaling configuration";

    container ldp {
      description
        "LDP global signaling configuration";

      container global {
        description
          "Platform wide LDP configuration and state";

        uses mpls-ldp-global;
        uses mpls-ldp-graceful-restart;
        uses mpls-ldp-authentication-top;
      }

      uses mpls-ldp-interface-attributes-top;
      uses mpls-ldp-targeted-top;
      uses mpls-ldp-neighbors-top;

    }
  }

  grouping mpls-ldp-authentication-top {
    description
    "Grouping containing LDP authentication attributes";

    container authentication {
      description
        "Global LDP authentication";

      container config {
          description
            "Configuration of LDP authentication attributes";
          uses mpls-ldp-authentication-config;
      }

      container state {
        config false;
        description
          "LDP authentication state.";
        uses mpls-ldp-authentication-config;
      }
    }
  }

  grouping mpls-ldp-neighbors-top {
    description
      "Global LDP neighbor attributes";

    container neighbors {
      description
        "State and configuration LDP neighbors attributes";

      list neighbor {
        key "lsr-id label-space-id";

        description
          "List of LDP neighbors and their attributes.";

        leaf lsr-id {
          type leafref {
            path "../config/lsr-id";
          }
          description
            "Neighbor label switch router identifier.";
        }

        leaf label-space-id {
          type leafref {
            path "../config/label-space-id";
          }
          description
            "Label space ID of the neighbor.";
        }

        container config {
          description
            "Neighbor configuration attributes.";
          uses mpls-ldp-neighbor-config;
        }

        container state {
          config false;
          description
            "Neighbor state attributes.";
          uses mpls-ldp-neighbor-config;
        }

        container hello-adjacencies {
          config false;
          description "Top container for hello adjacencies
            for a given LDP neighbor.";

          list hello-adjacency {
            key "remote-address local-address";
            config false;
            description
              "List of hello adjacencies for a given LDP
              neighbor.";

            leaf remote-address {
              config false;
              description
                "Within the LDP adjacency, this attribute
                shows the neighbor address.";
              type leafref {
                path "../state/remote-address";
              }
            }

            leaf local-address {
              config false;
              description
                "Within the LDP adjacency, this attribute
                shows the local address.";
              type leafref {
                path "../state/local-address";
              }
            }

            container state {
              description
                "State information for a particular LDP
                hello adjacency.";
              uses mpls-ldp-adjacency-state;
            }

            uses oc-if:interface-ref-state;

            container hello-holdtime {

              description
                "Specifies the time the sending LSR will
                maintain its record of Hellos from the
                receiving LSR";

              container state {
                description
                  "State attributes related to the
                  hello-holdtime.";
                config false;
                uses mpls-ldp-hello-holdtime-state;
              }
            }

          }
        }

        uses mpls-ldp-authentication-top;

      }
    }
  }

  grouping mpls-ldp-neighbor-config {
    description
      "Global configuration for LDP neighbors.";

    leaf lsr-id {
      type oc-inet:ip-address;
      description
        "Neighbor label switch router identifier.";
    }

    leaf label-space-id {
      type uint16;
      description
        "Label space ID of the neighbor.";
    }

  }

  grouping mpls-ldp-adjacency-state {

    description
      "Set of LDP neighbor related state attributes.";

    leaf remote-address {
      description
        "Within the LDP adjacency, this attribute
        shows the neighbor address.";
      type oc-inet:ip-address;
    }

    leaf local-address {
      description
        "Within the LDP adjacency, this attribute
        shows the local address.";
      type oc-inet:ip-address;
    }

    leaf adjacency-type {
      description
        "This attributes defines if the LDP
        adjacency is from a direct link or from
        targeted discovery.";
      type oc-ldp:mpls-ldp-adjacency-type;
    }

    leaf last-clear {
      type oc-types:timeticks64;
      description
        "Timestamp of the last time the interface counters
        were cleared. The value is the timestamp in
        nanoseconds relative to the Unix Epoch (Jan 1,
        1970 00:00:00 UTC).";
    }

    leaf hello-received {
      type oc-yang:counter64;
      description
        "Number of Hello messaged received by the device";
    }

    leaf hello-dropped {
      type oc-yang:counter64;
      description
        "Number of Hello messaged dropped by the device";
    }

  }

  grouping mpls-ldp-hello-holdtime-state {
    description
      "Grouping containing the state attributes
      for hello holdtime.";

    leaf adjacent {
      description
        "Hello holdtime attribute learned from the
        LDP neighbor";
      type uint16;
    }

    leaf negotiated {
      description
        "Hello holdtime attribute negotiated between
        the LDP neighbor and the local router.";
      type uint16;
    }

    leaf hello-expiration {
      description
        "Expiration time for the hello holdtime.";
      type oc-types:timeticks64;
    }

    leaf next-hello {
      description
        "Time when the next LDP hello will be sent to
        the adjacent neighbor.";
      type oc-types:timeticks64;
    }

  }

  grouping mpls-ldp-global {
    description
      "Global LDP attributes";

    container config {
      description
        "Global LDP configuration attributes.";
      uses mpls-ldp-global-config;
    }

    container state {
      config false;
      description
        "Global LDP state information.";
      uses mpls-ldp-global-config;
    }
  }

  grouping mpls-ldp-global-config {
    description
      "Grouping containing platform wide LDP information";

    leaf lsr-id {
      type oc-inet:ip-address;
      description
        "Global label switch router identifier
        configuration.";
      reference "RFC5036 LDP Specification";
    }

  }

  grouping mpls-ldp-interface-attributes-top {
    description
      "Top-level structure grouping for interface
      attributes";

    container interface-attributes {
      description
        "Container including attributes for LDP-enabled
        interfaces";

      container config {
        description
          "Configuration of per-interface LDP parameters";
        uses mpls-ldp-hello-timers-top-config;
      }

      container state {
        config false;
        description
          "Per-interface LDP protocol and state information";
        uses mpls-ldp-hello-timers-top-config;
      }

      container interfaces {
        description
          "Container aggregating all interfaces and their
          LDP-specific attributes.";

        list interface {
          key "interface-id";
          description
            "list of per-interface LDP configurations";

          leaf interface-id {
            type leafref {
              path "../config/interface-id";
            }
            description
              "reference to the interface-id data";
          }

          container config {
            description
              "Configuration of per-interface LDP parameters";
            uses mpls-ldp-interfaces-config;
            uses mpls-ldp-hello-timers-top-config;
          }

          container state {
            config false;
            description
              "Per-interface LDP protocol and state information";

            uses mpls-ldp-interfaces-config;
            uses mpls-ldp-hello-timers-top-config;

            container counters {
              config false;
              description
                "Interface specific LDP statistics and counters";
            }
          }

          uses oc-if:interface-ref;
          uses mpls-ldp-address-families-ldp-top;

        }
      }
    }
  }

  grouping mpls-ldp-address-families-ldp-top {
    description
      "Grouping containing the state and configuration
      attributes for adress families.";

    container address-families {
      description
        "Top container comprising the adress families
        attributes";
      list address-family {
        key "afi-name";
        description
          "List for attributes related to address-families for LDP.";

        leaf afi-name {
          type leafref {
                path "../config/afi-name";
              }
              description
                "Adress-family name atttibute (IPv4, IPv6).";
        }

        container config {
          description
            "Configuration attributes related to address-families
            for LDP.";
          uses mpls-ldp-address-family-config;
          uses admin-config;
        }

        container state {
          description
            "State attributes related to address-families for LDP.";
          config false;
          uses mpls-ldp-address-family-config;
          uses admin-config;
        }
      }
    }
  }

  grouping mpls-ldp-hello-timers-top-config {

    description
      "Grouping containing interface-related attributes
      that can be configured for LDP.";

    leaf hello-holdtime {
      type uint16;
      description
        "Defines the time for which a neighbor adjacency will
        be kept by the router while it waits for a new link
        Hello message.";
      reference "RFC5036 LDP Specification";
    }

    leaf hello-interval {
      type uint16;
      description
        "Defines the interval for sending Hello messages on
        each link LDP adjacency.";
    }

  }

  grouping mpls-ldp-targeted-top {

    description
      "Grouping containing attributes for targeted LDP";

    container targeted {
      description
        "Top container for targeted LDP state and configuration
        attributes.";

      container config {
        description
          "Configuration attributes related to targeted LDP.";
        uses mpls-ldp-targeted-attributes-top-config;
      }

      container state {
        config false;
        description
          "State attributes related to targeted LDP.";
        uses mpls-ldp-targeted-attributes-top-config;
      }

      uses mpls-ldp-address-targeted-ldp-top;
    }
  }

  grouping mpls-ldp-address-targeted-ldp-top {
    description
      "Grouping containing address attributes for targeted LDP.";

    container address-families {
      description
        "Global container for IPv4 and IPv6 attributes for LDP.";

      list address-family {
        key "afi-name";
        description
          "List of address families for targeted LDP
          configuration";

        leaf afi-name {
          type leafref {
                path "../config/afi-name";
              }
              description
                "Adress-family name atttibute (IPv4, IPv6).";
        }

        container config {
          description
            "Address-family configuration for targeted LDP";
          uses mpls-ldp-address-family-config;
        }

        container state {
          config false;
          description
            "Address-family state for targeted LDP";
          uses mpls-ldp-address-family-config;
        }

        container targets {
          description
            "Container aggregating all targeted sessions and
            their LDP-specific attributes.";

          list target {
            key "remote-address";

            description
              "List of LDP targets configuration";

            leaf remote-address {
              type leafref {
                path "../config/remote-address";
              }
              description
                "Neighbor address of the targeted LDP session";
            }

            container config {

              description
                "Configuration parameters of a targeted LDP
                adjacency";

              leaf remote-address {
                type oc-inet:ip-address;
                description
                  "Configuration of neighbor address of the
                  targeted LDP adjacency";
              }

              leaf local-address {
                type oc-inet:ip-address;
                description
                  "Local IP address of the LDP adjacency";
              }

              uses admin-config;
              uses mpls-ldp-hello-timers-top-config;
            }

            container state {
              config false;
              description
                "State attributes of a targeted LDP adjacency";

              leaf remote-address {
                config false;
                type oc-inet:ip-address;
                description
                  "Neighbor address of the targeted LDP adjacency";
              }

              leaf local-address {
                config false;
                type oc-inet:ip-address;
                description
                  "Local IP address of the LDP adjacency";
              }

              uses admin-config;
              uses mpls-ldp-hello-timers-top-config;
            }
          }
        }
      }
    }
  }

  grouping mpls-ldp-address-family-config {
    description
      "Grouping containing adress-family name atttibute";

    leaf afi-name {
      description
        "Adress-family name atttibute (IPv4, IPv6).";
      type oc-ldp:mpls-ldp-afi;
    }

  }

  grouping mpls-ldp-targeted-attributes-top-config {

    description
      "Grouping containing targeted LDP configuration
      attributes.";

    uses mpls-ldp-hello-timers-top-config;

    leaf hello-accept {
      type boolean;
      description
        "Enables or disables the acceptance of targeted LDP
        hello messages.";
      reference "RFC5036 LDP Specification";
    }

  }

  grouping mpls-ldp-interfaces-config {
    description
      "LDP configuration information relevant to an interface";

    leaf interface-id {
      type oc-if:interface-id;
      description
        "Identifier for the interface";
    }
  }

  grouping mpls-ldp-graceful-restart {
    description
      "Attributes relating to LDP Graceful-Restart";

    container graceful-restart {
      description
        "Top container for LDP graceful-restart attributes";

      container config {
        description
          "LDP graceful-restart configuration attributes.";
        uses mpls-ldp-graceful-restart-config;
      }

      container state {
        config false;
        description
          "LDP graceful-restart state attributes.";
        uses mpls-ldp-graceful-restart-config;
      }
    }
  }

  grouping mpls-ldp-graceful-restart-config {
    description
      "Configuration parameters relating to LDP Graceful-Restart";

    uses admin-config;

    leaf reconnect-time {
      type uint16;
      description
        "Interval for which the remote LDP peers
        will wait for the local node to reconnect after a
        failure";
      reference "RFC3478 Graceful Restart Mechanism for Label
        Distribution Protocol";
    }

    leaf recovery-time {
      type uint16;
      description
        "Interval used to specify the time for the remote
        peer to maintain the MPLS forwarding state after
        the local node has succesfully reconnected";
      reference "RFC3478 Graceful Restart Mechanism for Label
        Distribution Protocol";
    }

    leaf forwarding-holdtime {
      type uint16;
      description
        "Time that defines the interval for keeping the
        node in recovery mode.";
      reference "RFC3478 Graceful Restart Mechanism for Label
        Distribution Protocol";
    }

    leaf helper-enable {
      type boolean;
      description
        "Enables the graceful restart helper for LDP.";
    }
  }

  grouping igp-tunnel-ldp {
    description
      "common defintiions for LDP-signaled LSP tunnel
      types";
  }

  grouping igp-lsp-ldp-setup {
    description
      "grouping for LDP setup attributes";

    container ldp {
      description
        "LDP signaling setup for IGP-congruent LSPs";
      uses igp-tunnel-ldp;
    }
  }

  grouping mpls-ldp-authentication-config {
    description
      "LDP authentication parameters container.";

    leaf enable {
      type boolean;
      default false;
      description
        "Enables LDP authentication on the node.";
    }

    leaf authentication-key {
      type oc-types:routing-password;
      description
        "authenticate LDP signaling
         messages";
      reference
        "RFC1321 The MD5 Message-Digest Algorithm
        RFC5036 LDP Specification";
    }
  }

  grouping admin-config {
    description
      "Re-usable grouping to enable or disable a particular LDP feature.";

    leaf enabled {
      type boolean;
      default false;
      description
        "When set to true, the functionality within which this leaf is
        defined is enabled, when set to false it is explicitly disabled.";
    }
  }

  // data definition statements

  // augment statements

  // rpc statements

  // notification statements

}