module mef-topology {
  namespace "http://metroethernetforum.org/ns/yang/mef-topology";
  prefix mef-topology;
  import mef-types { prefix mef-types; }
  organization "Metro Ethernet Forum";
  contact
    "Web URL: http://metroethernetforum.org/ \\ E-mail: mibs@metroethernetforum.org
    \\ Postal: Metro Ethernet Forum \\ 6033 W. Century Boulevard,
    Suite 1107 \\ Los Angeles, CA 90045 \\ U.S.A. \\ Phone: +1 310-642-2800
    \\ Fax: +1 310-642-2808";
  description
    "This module models the NMS level view of the network devices,
    their physical interfaces, and the network topology. When the
    NMS discovers a network device,it is to pull the device configuration
    and operational status as expected for an NMS. Once the NMS has
    a network device's configuration, it creates the /mef-topology/devices/device{}
    entry and populates the list of physical interfaces. The Peers
    entries are populated as configuration to reflect physical cabling
    interconnections.Hints could be detected from LLDP Neighbor information[802.1AB].
    Reference Overview: A number of base documents have been used
    to create the MEF Topology YANG Module. The following are the
    abbreviations for the baseline documents: [RFC 6991] refers to
    IETF RFC 6991 'Common YANG Data Types', 2013-07-15 [RFC 6643]
    refers to IETF RFC 6643 'Translation of Structure of Management
    Information Version 2 (SMIv2) MIB Modules to YANG Modules', 2011-11-25
    [802.1AB] refers to 'Station and Media Access Control Connectivity
    Discovery', IEEE 802.1AB-2009, September 2009 [802.1q] refers
    to IEEE 802.1Q-2011 'IEEE Standard for Local and metropolitan
    area networks --Media Access Control (MAC) Bridges and Virtual
    Bridged Local Area Networks, August 2011 [802-2001] refers to
    'IEEE Standard for Local and Metropolitan Area Networks: Overview
    and Architecture', IEEE 802-2001, February 2002 [MEF10.3] refers
    to MEF 10.3 'Ethernet Services Attributes Phase 3', October 2013
    [MEF6.2] refers to MEF 6.2 'EVC Ethernet Services Defintions Phase
    3', August 2014 [MEF40] refers to MEF 40 'UNI and EVC Definition
    of Managed Objects', April 2013 [MEF45] refers to MEF 45 'Multi-CEN
    L2CP', August 2014 [MEF7.2] refers to MEF 7.2 'Carrier Ethernet
    Management Information Model', April 2013 [MEF7.3] refers to MEF
    7.3 'Carrier Ethernet Management Information Model', Working Draft
    #1 2015 [RFC 2737] refers to IETF RFC 2737 'Entity MIB (Version
    2)', December 1999 [RFC 2863] refers to IETF RFC 2863 'The Interfaces
    Group MIB', June 2000 [RFC 3419] refers to IETF RFC 3419 'Textual
    Conventions for Transport Addresses', December 2002 [Y.1731] refers
    to ITU-T Y.1731 'OAM functions and mechanisms for Ethernet based
    networks', July 2011 [Q.840.1] refers to ITU-T Q.840.1 'Requirements
    and analysis for NMS-EMS management interface of Ethernet over
    Transport and Metro Ethernet Network(EoT/MEN)' March 2007";
  revision 2015-05-26 {
    description
        "Formal Project Review Draft 1.";
    reference "EVC Ethernet Services Definitions YANG Modules " +
        "(MEF XX), TBD";
  }

  container mef-topology {
    description
        "MEF Topology";
    container devices {
      description
            "Network Devices in the CEN.";
      list device {
        key "dev-id";
        description
                "Network Device List.";
        container interfaces {
          description
                    "Physical Ports/Interfaces associated with this " +
                    "Network Device.";
          list interface {
            key "phy";
            description
                        "External Interface for the Network Device.";
            leaf phy {
              type mef-types:identifier45;
              description
                            "The Phy Name for the Physical Port.";
            }
            leaf ieee8023-phy {
              type identityref {
                base mef-types:ieee-8023-interface-type;
              }
              description
                            "The Physical Layer for each physical link " +
                            "implementing the UNI MUST be one of the PHYs " +
                            "listed in IEEE Std 802.3–2012 but excluding " +
                            "1000BASE-PX-D and 1000BASE-PX-U.";
              reference "[MEF10.3] Section 9.2 [R60].";
            }
          }
        }
        leaf role {
          type mef-types:device-role;
          default "ce";
          description
                    "The role of this device in the network.";
        }
        leaf dev-id {
          type mef-types:identifier45;
          description
                    "Device Identifier.";
        }
        leaf device-name {
          type string;
        }
      }
    }
    container connections {
      description
            "Physical Network Connections";
      list connection {
        key "name";
        leaf name {
          type mef-types:identifier45;
        }
        container endpoint-1 {
          description
                    "End Point 1";
          leaf device {
            type leafref {
              path "../../../../devices/device/dev-id";
            }
            description
                        "Hostname or IP Address for the End Point's Device.";
          }
          leaf interface {
            type leafref {
              path "../../../../devices/device[dev-id = current()/../device]/interfaces/interface/phy";
            }
            description
                        "The Phy Name for the End Point's Physical Port.";
          }
        }
        container endpoint-2 {
          description
                    "End Point 2";
          leaf device {
            type leafref {
              path "../../../../devices/device/dev-id";
            }
            description
                        "Hostname or IP Address for the End Point's Device.";
          }
          leaf interface {
            type leafref {
              path "../../../../devices/device[dev-id = current()/../device]/interfaces/interface/phy";
            }
            description
                        "The Phy Name for the End Point's Physical Port.";
          }
        }
      }
    }
  }
}