module ietf-network-state {

    yang-version 1.1;

    namespace
      "urn:ietf:params:xml:ns:yang:ietf-network-state";

    prefix nw-s;

    import ietf-network {
      prefix nw;
      reference
        "RFC 8345: A YANG Data Model for Network Topologies";


    }

    organization
      "IETF I2RS (Interface to the Routing System) Working Group";

    contact
      "WG Web:    <https://datatracker.ietf.org/wg/i2rs/>
WG List:   <mailto:i2rs@ietf.org>

Editor:    Alexander Clemm
	   <mailto:ludwig@clemm.org>

Editor:    Jan Medved
	   <mailto:jmedved@cisco.com>

Editor:    Robert Varga
	   <mailto:robert.varga@pantheon.tech>

Editor:    Nitin Bahadur
	   <mailto:nitin_bahadur@yahoo.com>
Editor:    Hariharan Ananthakrishnan
	   <mailto:hari@packetdesign.com>

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

    description
      "This module defines a common base data model for a collection
of nodes in a network.  Node definitions are further used
in network topologies and inventories.  It represents
information that either (1) is learned and automatically
populated or (2) results from applying network information
that has been configured per the 'ietf-network' data model,
mirroring the corresponding data nodes in this data model.

The data model mirrors 'ietf-network' but contains only
read-only state data.  The data model is not needed when the
underlying implementation infrastructure supports the Network
Management Datastore Architecture (NMDA).

Copyright (c) 2018 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 8345;
see the RFC itself for full legal notices.";

    revision "2018-02-26" {
      description "Initial revision.";
      reference
        "RFC 8345: A YANG Data Model for Network Topologies";

    }


    grouping network-ref {
      description
        "Contains the information necessary to reference a network --
for example, an underlay network.";
      leaf network-ref {
        type leafref {
          path
            "/nw-s:networks/nw-s:network/nw-s:network-id";
          require-instance false;
        }
        description
          "Used to reference a network -- for example, an underlay
network.";
      }
    }  // grouping network-ref

    grouping node-ref {
      description
        "Contains the information necessary to reference a node.";
      leaf node-ref {
        type leafref {
          path
            "/nw-s:networks/nw-s:network[nw-s:network-id=current()/../network-ref]/nw-s:node/nw-s:node-id";
          require-instance false;
        }
        description
          "Used to reference a node.
Nodes are identified relative to the network that
contains them.";
      }

      uses network-ref;
    }  // grouping node-ref

    container networks {
      config false;
      description
        "Serves as a top-level container for a list of networks.";
      list network {
        key "network-id";
        description
          "Describes a network.
A network typically contains an inventory of nodes,
topological information (augmented through the
network-topology data model), and layering information.";
        container network-types {
          description
            "Serves as an augmentation target.
The network type is indicated through corresponding
presence containers augmented into this container.";
        }  // container network-types

        leaf network-id {
          type nw:network-id;
          description
            "Identifies a network.";
        }

        list supporting-network {
          key "network-ref";
          description
            "An underlay network, used to represent layered network
topologies.";
          leaf network-ref {
            type leafref {
              path "/nw-s:networks/nw-s:network/nw-s:network-id";
              require-instance false;
            }
            description
              "References the underlay network.";
          }
        }  // list supporting-network

        list node {
          key "node-id";
          description
            "The inventory of nodes of this network.";
          leaf node-id {
            type nw:node-id;
            description
              "Uniquely identifies a node within the containing
network.";
          }

          list supporting-node {
            key "network-ref node-ref";
            description
              "Represents another node that is in an underlay network
and that supports this node.  Used to represent layering
structure.";
            leaf network-ref {
              type leafref {
                path "../../../nw-s:supporting-network/nw-s:network-ref";
                require-instance false;
              }
              description
                "References the underlay network of which the
underlay node is a part.";
            }

            leaf node-ref {
              type leafref {
                path "/nw-s:networks/nw-s:network/nw-s:node/nw-s:node-id";
                require-instance false;
              }
              description
                "References the underlay node itself.";
            }
          }  // list supporting-node
        }  // list node
      }  // list network
    }  // container networks
  }  // module ietf-network-state