module ieee802-dot1q-cfm {

    yang-version 1.1;

    namespace
      "urn:ieee:std:802.1Q:yang:ieee802-dot1q-cfm";

    prefix dot1q-cfm;

    import ieee802-dot1q-cfm-types {
      prefix cfm-types;
    }
    import ieee802-dot1q-types {
      prefix dot1q-types;
    }
    import ieee802-types {
      prefix ieee;
    }
    import ietf-yang-types {
      prefix yang;
    }
    import ietf-inet-types {
      prefix inet;
    }

    organization "IEEE 802.1 Working Group";

    contact
      "WG-URL: http://ieee802.org/1/
WG-EMail: stds-802-1-l@ieee.org

Contact: IEEE 802.1 Working Group Chair
Postal: C/O IEEE 802.1 Working Group
      IEEE Standards Association
      445 Hoes Lane
      Piscataway, NJ 08854
      USA

E-mail: stds-802-1-chairs@ieee.org";

    description
      "Connectivity Fault Management (CFM) comprises capabilities for
detecting, verifying, and isolating connectivity failures in Virtual
Bridged Local Area Networks. These capabilities can be used in networks
operated by multiple independent organizations, each with restricted
management access to each other's equipment.

Copyright (C) IEEE (2021).

This version of this YANG module is part of IEEE Std 802.1Q; see the
standard itself for full legal notices.";

    revision "2021-06-01" {
      description
        "Published as part of IEEE Std 802.1Q-2021.";
      reference
        "IEEE Std 802.1Q-2021, Bridges and Bridged Networks.";

    }

    revision "2020-06-04" {
      description
        "Published as part of IEEE Std 802.1Qcx-2020. Initial version.";
      reference
        "IEEE Std 802.1Qcx-2020, Bridges and Bridged Networks - YANG Data
        Model for Connectivity Fault Management.";

    }


    grouping mac-address-and-uint-type-grouping {
      description
        "The MAC address and uint type grouping.";
      container mac-address-and-uint-type {
        description
          "The MAC address and uint type definition.";
        leaf address {
          type ieee:mac-address;
          mandatory true;
          description "The MAC address.";
        }

        leaf int {
          type uint16;
          mandatory true;
          description
            "The additional 2-octet (unsigned) integer.";
        }
      }  // container mac-address-and-uint-type
    }  // grouping mac-address-and-uint-type-grouping

    grouping md-name-choice-grouping {
      description
        "The Maintenance Domain name and name format choice.";
      choice md-name {
        default "char-string";
        description
          "The Maintenance Domain name type.";
        leaf none {
          type empty;
          description
            "No format specified, usually because there is not a Maintenance
Domain Name. The Maintenance Domain name inserted in CFM
protocol messages will be a zero length OCTET string.";
        }
        leaf dns-like-name {
          type string {
            length "1..43";
          }
          description
            "Domain name like string, globally unique text string derived
from a DNS name.";
        }

        case mac-address-and-uint {
          description
            "MAC address plus 2-octet (unsigned) integer.";
          uses mac-address-and-uint-type-grouping;
        }  // case mac-address-and-uint
        leaf char-string {
          type string {
            length "1..43";
            pattern '[ -~]*';
          }
          default "DEFAULT";
          description
            "RFC2579 DisplayString, except that the character codes 0-31
(decimal) are not used.";
        }
      }  // choice md-name
    }  // grouping md-name-choice-grouping

    grouping ma-name-choice-grouping {
      description
        "The Maintenance Association name and name format choice.";
      choice ma-name {
        mandatory true;
        description
          "The Maintenance Association name type.";
        leaf primary-vid {
          type dot1q-types:vlanid;
          description
            "Primary VLAN ID. 12 bits represented in a 2-octet integer.";
        }
        leaf char-string {
          type string {
            length "1..45";
            pattern '';
          }
          description
            "RFC2579 DisplayString, except that the character codes 0-31
(decimal) are not used.";
        }
        leaf unsigned-int16 {
          type uint16;
          description "2-octet integer.";
        }
        container vpn-id {
          description
            "RFC2685 VPN ID. 3 octet VPN authority Organizationally Unique
Identifier followed by 4 octet VPN index identifying VPN
according to the OUI.";
          leaf vpn-oui {
            type uint32 {
              range "0..16777215";
            }
            mandatory true;
            description
              "3 octet VPN authority Organizationally Unique Identifier.";
          }

          leaf vpn-index {
            type uint32;
            mandatory true;
            description
              "4 octet VPN index identifying VPN according to OUI.";
          }
        }  // container vpn-id
      }  // choice ma-name
    }  // grouping ma-name-choice-grouping

    grouping management-address-grouping {
      description
        "Defines the Management Address.";
      reference
        "21.5.3.5 of IEEE Std 802.1Q-2021";

      leaf domain {
        type yang:object-identifier-128;
        description "The domain type.";
      }

      choice management-address {
        when "./domain";
        mandatory true;
        description
          "Selects the management address";
        case ip {
          description
            "Represents an IP TCP, UDP, or SCTP transport address consisting
of an IPv4/v6 address, and a port number, associated with the
domain type defined by the domain leaf node.";
          leaf ip-address {
            type inet:ip-address;
            mandatory true;
            description
              "IPv4 or IPv6 address.";
          }

          leaf ip-port {
            type inet:port-number;
            mandatory true;
            description "IP port.";
          }
        }  // case ip
        leaf local-address {
          type string {
            length "1..255";
          }
          mandatory true;
          description
            "Represents a POSIX Local IPC transport address, associated with
the domain type defined by the domain leaf node.";
        }
        leaf dns-address {
          type string {
            length "1..255";
          }
          mandatory true;
          description
            "The transport domain using fully qualified domain names,
associated with the domain type defined by the domain leaf node.
Represents a DNS domain name followed by a colon ':' (ASCII
character 0x3A) and a port number in ASCII. The name SHOULD be
fully qualified whenever possible.";
        }
        leaf unknown-address {
          type binary {
            length "1..255";
          }
          description
            "This represents an undefined address, for the case when the
domain type provided is an unrecognizable value.";
        }
      }  // choice management-address
    }  // grouping management-address-grouping

    grouping loopback-input-grouping {
      description
        "Defines the group of loopback input parameters.";
      choice lbm-destination {
        mandatory true;
        description
          "Selects the destination type (which is either MEP identifier or MAC
address) used for the Loopback transmissions.";
        case dest-ucast-mac-address {
          description
            "The target unicast MAC Address field to be transmitted. A unicast
destination MAC address.";
          leaf lbm-dest-ucast-mac-address {
            type cfm-types:unicast-mac-address-type;
            description
              "The target MAC Address field to be transmitted. A unicast
destination MAC address.";
            reference
              "12.14.7.3.2b of IEEE Std 802.1Q-2021";

          }
        }  // case dest-ucast-mac-address

        case dest-mcast-class1-mac-address {
          description
            "The target multicast Class 1 MAC address field to be transmitted.";
          leaf lbm-dest-mcast-class1-mac-address {
            type cfm-types:multicast-class1-mac-address-type;
            description
              "The target multicast Class 1 MAC address field to be
transmitted";
          }
        }  // case dest-mcast-class1-mac-address

        case dest-mep-id {
          description
            "The identifier of a remote MEP in the same MA to which the LBM is
to be sent.";
          leaf lbm-dest-mep-id {
            type cfm-types:mep-id-type;
            description
              "The identifier of a remote MEP in the same MA to which the LBM
is to be sent.";
            reference
              "12.14.7.3.2b of IEEE Std 802.1Q-2021";

          }
        }  // case dest-mep-id
      }  // choice lbm-destination

      leaf lbm-messages {
        type uint16 {
          range "1..1024";
        }
        default "1";
        description
          "The number of Loopback messages to be transmitted.";
        reference
          "12.14.7.3.2c of IEEE Std 802.1Q-2021";

      }

      leaf lbm-priority {
        type dot1q-types:priority-type;
        default "7";
        description
          "Priority. 3 bit value to be used in the VLAN tag, if present in the
transmitted frame. The default value should be priority 7, which is
the default CCM priority (ccm-ltm-priority).";
        reference
          "12.14.7.3.2e of IEEE Std 802.1Q-2021";

      }

      leaf lbm-drop-eligible {
        type boolean;
        default "false";
        description
          "Drop eligible bit value to be used in the VLAN tag, if present in
the transmitted frame. A value 'true' means inserting value '1' in
the DEI field, while a value 'false' means inserting value '0' in
the DEI field.";
        reference
          "12.14.7.3.2e of IEEE Std 802.1Q-2021";

      }

      leaf lbm-data-tlv {
        type cfm-types:lbm-data-tlv-type;
        description
          "An arbitrary amount of data to be included in the Data TLV, if the
Data TLV is selected to be sent.";
        reference
          "12.14.7.3.2d of IEEE Std 802.1Q-2021";

      }
    }  // grouping loopback-input-grouping

    grouping linktrace-input-grouping {
      description
        "Defines the group of linktrace input parameters. By default, the
priority used is that of the CCMs (ccm-ltm-priority) and the drop
eligibility is false.";
      choice ltr-target {
        mandatory true;
        description
          "Selects the target address type (which is either MEP identifier or
MAC address) used for the Linktrace transmissions.";
        case target-ucast-mac-address {
          description
            "The target MAC address field to be transmitted. A unicast MAC
address.";
          leaf ltm-target-mac-address {
            type cfm-types:unicast-mac-address-type;
            description
              "The target MAC address field to be transmitted. A unicast MAC
address.";
            reference
              "12.14.7.4.2c of IEEE Std 802.1Q-2021";

          }
        }  // case target-ucast-mac-address

        case target-mep-id {
          description
            "The MEP identifier of another MEP in the same MA.";
          leaf ltm-target-mep-id {
            type cfm-types:mep-id-type;
            description
              "The MEP identifier of another MEP in the same MA.";
            reference
              "12.14.7.4.2c of IEEE Std 802.1Q-2021";

          }
        }  // case target-mep-id
      }  // choice ltr-target

      leaf ltm-ttl {
        type uint8 {
          range "0..255";
        }
        default "64";
        description
          "The LTM TTL field. Indicates the number of hops remaining to the
LTM. Decremented by 1 by each Linktrace Responder that handles the
LTM. The value returned in the LTR is one less than that received in
the LTM. If the LTM TTL is 0 or 1, the LTM is not forwarded to the
next hop, and if 0, no LTR is generated.";
        reference
          "12.14.7.4.2d, 21.8.4 of IEEE Std 802.1Q-2021";

      }

      leaf ltm-flags {
        type cfm-types:mep-tx-ltm-flags-type;
        default "";
        description
          "The flags field for the LTMs transmitted by the MEP.";
        reference
          "12.14.7.4.2b, 20.42.1 of IEEE Std 802.1Q-2021";

      }
    }  // grouping linktrace-input-grouping

    grouping ltm-egress-identifier-grouping {
      description
        "The grouping used to identify the MEP Linktrace initiator that is
originating the LTM. It defines the MAC address and uint type
definition.";
      leaf int {
        type uint16;
        mandatory true;
        description
          "A value used to uniquely identify the MEP Linktrace Initiator or
Linktrace Responder within that system.";
      }

      leaf address {
        type ieee:mac-address;
        mandatory true;
        description
          "A 48-bit IEEE MAC address unique to the system in which the MEP
Linktrace Initiator or Linktrace Responder resides.";
      }
    }  // grouping ltm-egress-identifier-grouping

    container cfm {
      description
        "Connectivity Fault Management configuration and operational
information.";
      list maintenance-domain {
        key "md-id";
        description
          "Contains the Maintenance Domain configuration and operational data.
A Maintenance Domain is the network or the part of the network for
which faults in connectivity can be managed. The boundary of a
Maintenance Domain is defined by a set of Domain Service Access
Points (DoSAPs), each of which can become a point of connectivity to
a service instance.";
        leaf md-id {
          type cfm-types:name-key-type;
          description
            "The index to the Maintenance Domain list.";
        }

        uses md-name-choice-grouping;

        leaf md-level {
          type cfm-types:md-level-type;
          default "0";
          description
            "The Maintenance Domain level.";
          reference
            "3.123, 12.14.5.1.3b of IEEE Std 802.1Q-2021";

        }

        leaf mhf-creation {
          type cfm-types:mhf-creation-type;
          must ". != 'mhf-defer'" {
            description
              "The value mhf-defer is not allowed";
          }
          default "mhf-none";
          description
            "Value indicating whether the management entity can create MHFs
(MIP Half Function) for this Maintenance Domain. Since there is no
encompassing Maintenance Domain, the value mhf-defer is not
allowed.";
          reference
            "3.123, 12.14.5.1.3c of IEEE Std 802.1Q-2021";

        }

        leaf id-permission {
          type cfm-types:sender-id-permission-type;
          must ". != 'send-id-defer'" {
            description
              "The value send-id-defer is not allowed";
          }
          default "send-id-none";
          description
            "Value indicating what, if anything, is to be included in the
Sender ID TLV transmitted by Maintenance Points configured in this
Maintenance Domain. Since there is no encompassing Maintenance
Domain, the value send-id-defer is not allowed.";
          reference
            "3.123, 12.14.5.1.3d of IEEE Std 802.1Q-2021";

        }

        leaf fault-alarm-transmission {
          type cfm-types:fault-alarm-type;
          default "not-transmitted";
          description
            "A value indicating whether Fault Alarms are to be transmitted or
not. The default is not transmit.";
          reference
            "3.123, 12.14.5.1.3e of IEEE Std 802.1Q-2021";

        }

        list maintenance-association {
          key "ma-id";
          description
            "Provides configuration and operational data for the Maintenance
Associations. A Maintenance Association is a set of MEPs, each
configured with the same MAID and MD level, established to verify
the integrity of a single service instance. A Maintenance
Association can be thought of as a full mesh of Maintenance
Entities among a set of MEPs so configured.";
          leaf ma-id {
            type cfm-types:name-key-type;
            description
              "Key of the Maintenance Association list of entries.";
          }

          uses ma-name-choice-grouping;

          leaf ccm-interval {
            type cfm-types:ccm-interval-type;
            default "1sec";
            description
              "The interval between CCM transmissions to be used by all MEPs
in the Maintenance Association.";
            reference
              "12.14.6.1.3e of IEEE Std 802.1Q-2021";

          }

          leaf fault-alarm-transmission {
            type cfm-types:fault-alarm-type;
            description
              "A value indicating whether Fault Alarms are to be transmitted
or not. If this leaf node is not present then the disposition of
the fault-alarm used by the MD should be used.";
            reference
              "3.123, 12.14.5.1.3e of IEEE Std 802.1Q-2021";

          }

          leaf mhf-creation {
            type cfm-types:mhf-creation-type;
            default "mhf-defer";
            description
              "Value indicating whether the management entity can create MHFs
(MIP Half Function) for this Maintenance Association.";
            reference
              "3.123, 12.14.5.1.3c of IEEE Std 802.1Q-2021";

          }

          leaf id-permission {
            type cfm-types:sender-id-permission-type;
            default "send-id-defer";
            description
              "Enumerated value indicating what, if anything, is to be
included in the Sender ID TLV (21.5.3) transmitted by MPs
configured in this MA.";
            reference
              "12.14.3.1.3d of IEEE Std 802.1Q-2021";

          }

          list maintenance-association-mep {
            key "mep-id";
            description
              "The list of all MEPs that belong to this Maintenance
Association.";
            leaf mep-id {
              type cfm-types:mep-id-type;
              description
                "Integer that is unique among all the MEPs in the same
Maintenance Association.";
              reference
                "12.14.6.1.3g of IEEE Std 802.1Q-2021";

            }
          }  // list maintenance-association-mep
        }  // list maintenance-association
      }  // list maintenance-domain

      list maintenance-group {
        key "maintenance-group-id";
        description
          "The list of maintenance association groups, which are uniquely
associated with a maintenance domain, maintenance association, for
which the MEPs belong.";
        leaf maintenance-group-id {
          type cfm-types:name-key-type;
          description
            "The maintenance group provides a handle for the MD and MA
combination.";
        }

        leaf md-id {
          type leafref {
            path "/cfm/maintenance-domain/md-id";
          }
          mandatory true;
          description
            "A reference to the maintenance domain that this maintenance group
is associated with.";
        }

        leaf ma-id {
          type leafref {
            path "/cfm/maintenance-domain[md-id = current()/../md-id]/maintenance-association/ma-id";
          }
          mandatory true;
          description
            "A reference to the maintenance association in the specified
maintenance domain, that this maintenance group is associated
with.";
        }

        list mep {
          key "mep-id";
          description
            "A list of local Maintenance association End Points (MEPs). A MEP
is an actively managed CFM entity, associated with a specific
DoSAP of a service instance, which can generate and receive CFM
PDUs and track any responses. It is an end point of a single
Maintenance Association (MA) and is an end point of a separate
Maintenance Entity for each of the other MEPs in the same MA.";
          leaf mep-id {
            type leafref {
              path "/cfm/maintenance-domain[md-id = current()/../../md-id]/maintenance-association[ma-id = current()/../../ma-id]/maintenance-association-mep/mep-id";
            }
            description
              "Integer that is unique among all the MEPs in the same
Maintenance Association.";
            reference
              "3.115, 12.14.7, 19.2 of IEEE Std 802.1Q-2021";

          }

          leaf direction {
            type cfm-types:mp-direction-type;
            mandatory true;
            description
              "The direction in which the MEP faces on the Bridge Port.
Example, up or down.";
            reference
              "12.14.7.1.3c, 19.2 of IEEE Std 802.1Q-2021";

          }

          leaf enabled {
            type boolean;
            default "false";
            description
              "The administrative state of the MEP. TRUE indicates that the
MEP is to functional normally, and FALSE indicates that it is to
cease functioning.";
            reference
              "12.14.7.1.3e, 20.9.1 of IEEE Std 802.1Q-2021";

          }

          leaf ccm-ltm-priority {
            type dot1q-types:priority-type;
            default "7";
            description
              "The priority value for CCMs and LTMs transmitted by the MEP.
The default value is the highest priority allowed to pass
through the Bridge Port for any of the MEPs VID(s).";
            reference
              "12.14.7.1.3h of IEEE Std 802.1Q-2021";

          }

          leaf mac-address {
            type ieee:mac-address;
            config false;
            mandatory true;
            description
              "The MAC address of the MEP.";
            reference
              "12.14.7.1.3i, 19.4 of IEEE Std 802.1Q-2021";

          }

          list inactive-remote-mep {
            key "inactive-rmep-id";
            description
              "A list indicating which of the remote MEPs in the same MA are
inactive. The Remote MEP state machines (20.20) are instantiated
only for the remote MEPs which are present in the
maintenance-association-mep-list, but not in this list. By
default, all configured remote MEPs in the same MA are active";
            leaf inactive-rmep-id {
              type leafref {
                path "/cfm/maintenance-domain[md-id = current()/../../../md-id]/maintenance-association[ma-id = current()/../../../ma-id]/maintenance-association-mep/mep-id";
              }
              description
                "Maintenance association Endpoint Identifier of a remote MEP
for which the Remote MEP state machine should not be
instantiated.";
              reference
                "12.14.7.1.3ae of IEEE Std 802.1Q-2021";

            }
          }  // list inactive-remote-mep

          list mep-db {
            key "rmep-id";
            config false;
            description
              "The MEP CCM Database. A database, maintained by every MEP, that
maintains received information about other MEPs in the
Maintenance Association.";
            leaf rmep-id {
              type cfm-types:mep-id-type;
              description
                "Maintenance association Endpoint Identifier of a remote MEP
whose information from the MEP Database is to be returned.";
              reference
                "12.14.7.6.2b of IEEE Std 802.1Q-2021";

            }

            leaf rmep-state {
              type cfm-types:remote-mep-state-type;
              mandatory true;
              description
                "The operational state of the remote MEP state machine";
              reference
                "12.14.7.6.3b, 20.20 of IEEE Std 802.1Q-2021";

            }

            leaf rmep-failed-ok-time {
              type yang:timeticks;
              mandatory true;
              description
                "The time (SysUpTime) at which the Remote MEP state machine
last entered either the RMEP_FAILED or RMEP_OK state";
              reference
                "12.14.7.6.3c of IEEE Std 802.1Q-2021";

            }

            leaf mac-address {
              type ieee:mac-address;
              mandatory true;
              description
                "The MAC address of the remote MEP.";
              reference
                "12.14.7.6.3d, 20.19.7 of IEEE Std 802.1Q-2021";

            }

            leaf rdi {
              type boolean;
              mandatory true;
              description
                "State of the RDI bit in the last received CCM (true for
RDI=1), or false if none has been received.";
              reference
                "12.14.7.6.3e, 20.19.2 of IEEE Std 802.1Q-2021";

            }

            leaf port-status-tlv {
              type cfm-types:port-status-tlv-value-type;
              description
                "An enumerated value of the Port status TLV received in the
last CCM from the remote MEP or the default value
no-port-state-tlv indicating either no CCM has been received,
or that no port status TLV was received in the last CCM.";
              reference
                "12.14.7.6.3f, 20.19.3 of IEEE Std 802.1Q-2021";

            }

            leaf interface-status-tlv {
              type cfm-types:interface-status-tlv-value-type;
              description
                "An enumerated value of the Interface status TLV received in
the last CCM from the remote MEP or the default value
is-no-interface-status-tlv indicating either no CCM has been
received, or that no interface status TLV was received in the
last CCM.";
              reference
                "12.14.7.6.3g, 20.19.4 of IEEE Std 802.1Q-2021";

            }

            leaf chassis-id-subtype {
              type ieee:chassis-id-subtype-type;
              description
                "This object specifies the format of the Chassis ID received
in the last CCM.";
              reference
                "12.14.7.6.3h, 21.5.3.2 of IEEE Std 802.1Q-2021";

            }

            leaf chassis-id {
              type ieee:chassis-id-type;
              description
                "The Chassis ID. The format of this object is determined by
the value of the ltr-chassis-id-subtype object.";
              reference
                "12.14.7.6.3h, 21.5.3.3 of IEEE Std 802.1Q-2021";

            }

            container transport-service-domain {
              description
                "The transport management domain and address.";
              reference
                "12.14.7.6.3h, 21.5.3.5, 21.5.3.7,
                21.6.7 of IEEE Std 802.1Q-2021";

              uses management-address-grouping;
            }  // container transport-service-domain

            leaf rmep-is-active {
              type boolean;
              default "true";
              description
                "A Boolean value stating if the remote MEP is active.";
              reference
                "12.14.7.1.3ae";

            }
          }  // list mep-db

          container continuity-check {
            description
              "Continuity check protocol";
            leaf ccm-enabled {
              type boolean;
              default "false";
              description
                "Indicates whether the MEP can generate CCMs. If TRUE, the MEP
will generate CCM PDUs.";
              reference
                "12.14.7.1.3g, 20.10.1 of IEEE Std 802.1Q-2021";

            }

            leaf fng-state {
              type cfm-types:fng-state-type;
              default "fng-reset";
              config false;
              description
                "The current state of the MEP Fault Notification Generator
state machine.";
              reference
                "12.14.7.1.3f, 20.35 of IEEE Std 802.1Q-2021";

            }

            leaf fault-alarm-transmission {
              type cfm-types:fault-alarm-type;
              description
                "A value indicating whether Fault Alarms are to be transmitted
or not. If this leaf is not specified, the disposition of the
fault-alarm used by the MD should be used.";
              reference
                "3.124, 12.14.7.1.3j of IEEE Std 802.1Q-2021";

            }

            leaf lowest-priority-defect {
              type cfm-types:lowest-alarm-priority-type;
              default
                "mac-remote-error-xcon";
              description
                "The lowest priority defect that is allowed to generate fault
alarms.";
              reference
                "12.14.7.1.3k, 20.9.5 of IEEE Std 802.1Q-2021";

            }

            leaf fng-alarm-time {
              type uint16 {
                range "2500..10000";
              }
              units "milliseconds";
              default "2500";
              description
                "The time that defect must be present before a Fault Alarm is
issued.";
              reference
                "12.14.7.1.3l, 20.35.3 of IEEE Std 802.1Q-2021";

            }

            leaf fng-reset-time {
              type uint16 {
                range "2500..10000";
              }
              units "milliseconds";
              default "10000";
              description
                "The time that defects must be absent before resetting a Fault
Alarm.";
              reference
                "12.14.7.1.3m, 20.35.4 of IEEE Std 802.1Q-2021";

            }

            leaf highest-priority-defect {
              type cfm-types:highest-defect-priority-type;
              config false;
              mandatory true;
              description
                "The highest priority defect that has been present since the
MEPs Fault Notification Generator state machine was last in
the FNG_RESET state.";
              reference
                "12.14.7.1.3n, 20.35.9 of IEEE Std 802.1Q-2021";

            }

            leaf defects {
              type cfm-types:mep-defects-type;
              config false;
              mandatory true;
              description
                "Vector of boolean error conditions";
              reference
                "12.14.7.1.3o-s, 20.21.3,
                20.23.3, 20.35.5, 20.35.6, 20.35.7 of IEEE Std
                802.1Q-2021";

            }

            leaf error-ccm-last-failure {
              type binary {
                length "1..128";
              }
              config false;
              description
                "The last received CCM that triggered a def-error-ccm fault.";
              reference
                "12.14.7.1.3t, 20.21.2 of IEEE Std 802.1Q-2021";

            }

            leaf xcon-ccm-last-failure {
              type binary {
                length "1..128";
              }
              config false;
              description
                "The last received CCM that triggered a def-xcon-ccm fault.";
              reference
                "12.14.7.1.3u, 20.23.2 of IEEE Std 802.1Q-2021";

            }
          }  // container continuity-check

          container stats {
            config false;
            description
              "Contains the counters associated with the MEP.";
            leaf mep-ccm-sequence-errors {
              type yang:counter64;
              mandatory true;
              description
                "The total number of out-of-sequence CCMs received from all
remote MEPs.";
              reference
                "12.14.7.1.3v, 20.16.12 of IEEE Std 802.1Q-2021";

            }

            leaf mep-ccms-sent {
              type yang:counter64;
              mandatory true;
              description
                "Total number of CCMs transmitted";
              reference
                "12.14.7.1.3w, 20.10.2 of IEEE Std 802.1Q-2021";

            }

            leaf mep-lbr-in {
              type yang:counter64;
              mandatory true;
              description
                "Total number of valid, in-order Loopback Replies received.";
              reference
                "12.14.7.1.3y, 20.31.1 of IEEE Std 802.1Q-2021";

            }

            leaf mep-lbr-in-out-of-order {
              type yang:counter64;
              mandatory true;
              description
                "The total number of valid, out-of-order Loopback Replies
received";
              reference
                "12.14.7.1.3z, 20.31.1 of IEEE Std 802.1Q-2021";

            }

            leaf mep-lbr-bad-msdu {
              type yang:counter64;
              mandatory true;
              description
                "The total number of LBRs received whose mac_service_data_unit
did not match (except for the OpCode) that of the
corresponding LBM.";
              reference
                "12.14.7.1.3aa, 20.2.3 of IEEE Std 802.1Q-2021";

            }

            leaf mep-unexpected-ltr-in {
              type yang:counter64;
              mandatory true;
              description
                "The total number of unexpected LTRs received.";
              reference
                "12.14.7.1.3ac, 20.44.1 of IEEE Std 802.1Q-2021";

            }

            leaf mep-lbr-out {
              type yang:counter64;
              mandatory true;
              description
                "Total number of Loopback Replies transmitted.";
              reference
                "12.14.7.1.3ad, 20.28.2 of IEEE Std 802.1Q-2021";

            }
          }  // container stats

          list linktrace-reply {
            key "ltr-transaction-id";
            config false;
            description
              "This list extends the MEP table and reports on accepted
transmit-linktrace actions. In case linktrace replies are
received it also reports with data from the received Linktrace
reply messages.";
            leaf ltr-transaction-id {
              type cfm-types:seq-number-type;
              description
                "Transaction identifier returned by a previous transmit
linktrace message command, indicating which LTMs response is
going to be returned.";
              reference
                "12.14.7.5.2b of IEEE Std 802.1Q-2021";

            }

            container linktrace-input {
              description
                "The linktrace parameter input. By default, the priority used
is that of the CCMs (ccm-ltm-priority) and the drop elibility
is false.";
              uses linktrace-input-grouping;
            }  // container linktrace-input

            list responses {
              key "ltr-receive-order";
              description
                "The responses associated with the request.";
              leaf ltr-receive-order {
                type uint32 {
                  range "1..4294967295";
                }
                description
                  "An index to distinguish among multiple LTRs with the same
LTR Transaction Identifier field value. Assigned
sequentially from 1, in the order that the Linktrace
Initiator received the LTRs.";
              }

              leaf ltr-ttl {
                type uint8 {
                  range "0..255";
                }
                mandatory true;
                description
                  "TTL field value for a returned LTR.";
                reference
                  "12.14.7.5, 20.41.2.2 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-forwarded {
                type boolean;
                mandatory true;
                description
                  "Indicates if an LTM was forwarded by the responding MP, as
returned in the FwdYes flag of the flags field.";
                reference
                  "12.14.7.5.3c, 20.41.2.1 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-terminal-mep {
                type boolean;
                mandatory true;
                description
                  "A Boolean value stating whether the forwarded LTM reached a
MEP enclosing its MA, as returned in the Terminal MEP flag
of the Flags field";
                reference
                  "12.14.7.5.3d, 20.41.2.1 of IEEE Std 802.1Q-2021";

              }

              container ltr-last-egress-identifier {
                description
                  "An octet field holding the Last Egress Identifier returned
in the LTR Egress Identifier TLV of the LTR. The Last Egress
Identifier identifies the MEP Linktrace Initiator that
originated, or the Linktrace Responder that forwarded, the
LTM to which this LTR is the response. This is the same
value as the Egress Identifier TLV of that LTM.";
                reference
                  "12.14.7.5.3e, 20.41.2.3 of IEEE Std 802.1Q-2021";

                uses ltm-egress-identifier-grouping;
              }  // container ltr-last-egress-identifier

              container ltr-next-egress-identifier {
                description
                  "An octet field holding the Next Egress Identifier returned
in the LTR Egress Identifier TLV of the LTR. The Next Egress
Identifier Identifies the Linktrace Responder that
transmitted this LTR, and can forward the LTM to the next
hop. This is the same value as the Egress Identifier TLV of
the forwarded LTM, if any. If the FwdYes bit of the Flags
field is false, the contents of this field are undefined,
i.e., any value can be transmitted, and the field is ignored
by the receiver.";
                reference
                  "12.14.7.5.3f, 20.41.2.4 of IEEE Std 802.1Q-2021";

                uses ltm-egress-identifier-grouping;
              }  // container ltr-next-egress-identifier

              leaf ltr-relay {
                type cfm-types:relay-action-field-value-type;
                mandatory true;
                description
                  "Value returned in the Relay Action field.";
                reference
                  "12.14.7.5.3g, 20.41.2.5 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-chassis-id-subtype {
                type ieee:chassis-id-subtype-type;
                description
                  "Specifies the format of the Chassis ID returned in the
Sender ID TLV of the LTR, if any. This leaf is not present
if the LTR did not contain a Sender ID TLV or if the Sender
ID TLV did not contain a Chassis ID.";
                reference
                  "12.14.7.5.3h, 21.5.3.2 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-chassis-id {
                when
                  "../ltr-chassis-id-subtype";
                type ieee:chassis-id-type;
                mandatory true;
                description
                  "The Chassis ID returned in the Sender ID TLV of the LTR, if
any. The format of this object is determined by the value of
the ltr-chassis-id-subtype object. This leaf is not present
if the LTR did not contain a Sender ID TLV or if the Sender
ID TLV did not contain a Chassis ID.";
                reference
                  "12.14.7.5.3i, 21.5.3.2 of IEEE Std 802.1Q-2021";

              }

              container ltr-transport-service-domain {
                description
                  "The transport management domain and address. This container
is empty if the LTR did not contain a Sender ID TLV or if
the Sender ID TLV did not contain a Management Address.";
                reference
                  "12.14.7.5.3j, 21.5.3.5, 21.5.3.7,
                  21.9.6 of IEEE Std 802.1Q-2021";

                uses management-address-grouping;
              }  // container ltr-transport-service-domain

              leaf ltr-ingress {
                type cfm-types:ingress-action-field-value-type;
                description
                  "The value returned in the Ingress Action Field of the LTM.
This leaf is not present if no Reply Ingress TLV was
returned in the LTM.";
                reference
                  "12.14.7.5.3k, 20.41.2.6 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-ingress-mac {
                when "../ltr-ingress";
                type ieee:mac-address;
                mandatory true;
                description
                  "MAC address returned in the ingress MAC address field. This
leaf is not present if the ltr-ingress leaf is not present.";
                reference
                  "12.14.7.5.3l, 20.41.2.7 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-ingress-port-id-subtype {
                when "../ltr-ingress";
                type ieee:port-id-subtype-type;
                description
                  "Format of the ingress Port ID. This leaf is not present if
the ltr-ingress leaf is not present, or if the Reply Ingress
TLV did not contain a Port ID.";
                reference
                  "12.14.7.5.3m, 20.41.2.8 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-ingress-port-id {
                when
                  "../ltr-ingress and ../ltr-ingress-port-id-subtype";
                type ieee:port-id-type;
                mandatory true;
                description
                  "Ingress Port ID. The format of this object is determined by
the value of the ltr-ingress-port-id-subtype object. This
leaf is not present if the ltr-ingress leaf or the
ltr-ingress-port-id-subtype leaf are not present.";
                reference
                  "12.14.7.5.3n, 20.41.2.9 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-egress {
                type cfm-types:egress-action-field-value-type;
                description
                  "The value returned in the Egress Action Field of the LTM.
The node is not present if no Reply Egress TLV was returned
in the LTM.";
                reference
                  "12.14.7.5.3o, 20.41.2.10 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-egress-mac {
                when "../ltr-egress";
                type ieee:mac-address;
                mandatory true;
                description
                  "MAC address returned in the egress MAC address field. This
leaf is not present if the ltr-egress leaf is not present.";
                reference
                  "12.14.7.5.3p, 20.41.2.11 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-egress-port-id-subtype {
                when "../ltr-egress";
                type ieee:port-id-subtype-type;
                description
                  "Format of the egress Port ID. This leaf is not present if
the ltr-egress leaf is not present, or if the Reply Egress
TLV did not contain a Port ID.";
                reference
                  "12.14.7.5.3q, 20.41.2.12 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-egress-port-id {
                when
                  "../ltr-egress and ../ltr-egress-port-id-subtype";
                type ieee:port-id-type;
                mandatory true;
                description
                  "Egress Port ID. The format of this object is determined by
the value of the ltr-egress-port-id-subtype object. This
leaf is not present if the ltr-egress leaf or the
ltr-egress-port-id-subtype leaf are not present.";
                reference
                  "12.14.7.5.3r, 20.41.2.13 of IEEE Std 802.1Q-2021";

              }

              leaf ltr-organization-specific-tlv {
                type binary {
                  length "0 | 4..1500";
                }
                description
                  "All Organization specific TLVs returned in the LTR, if any.
Includes all octets including and following the TLV Length
field of each TLV, concatenated together.";
                reference
                  "12.14.7.5.3s, 21.5.2 of IEEE Std 802.1Q-2021";

              }
            }  // list responses
          }  // list linktrace-reply

          action transmit-loopback {
            description
              "To signal to the MEP to transmit some number of LBMs. Accepting
the action means the device will transmit LBM messages according
the input leaf nodes.";
            input {
              uses loopback-input-grouping;
            }

            output {
              leaf lbm-request-id {
                type cfm-types:seq-number-type;
                mandatory true;
                description
                  "The Loopback transaction identifier of the first LBM (to
be) sent.";
                reference
                  "12.14.7.3.3b of IEEE Std 802.1Q-2021";

              }
            }
          }  // rpc transmit-loopback

          action transmit-linktrace {
            description
              "To signal to the MEP to transmit an LTM and to create an LTM
entry in the MEPs Linktrace Database. Accepting the action means
the device will transmit LTM messages according to the input
leafs. The outcome of sending these LTM messages will be
reported through the list 'linktrace-reply'.";
            input {
              uses linktrace-input-grouping;
            }

            output {
              leaf ltm-transaction-id {
                type cfm-types:seq-number-type;
                mandatory true;
                description
                  "The LTM transaction identifier of the LTM sent. The value
returned is undefined if and RPC error is returned.";
                reference
                  "12.14.7.4.3b of IEEE Std 802.1Q-2021";

              }

              container ltm-egress-identifier {
                description
                  "Identifies the MEP Linktrace Initiator that is originating
this LTM.

The low-order six octets contain a 48-bit IEEE MAC address
unique to the system in which the MEP Linktrace Initiator or
Linktrace Responder resides. The high-order two octets
contain a value sufficient to uniquely identify the MEP
Linktrace Initiator or Linktrace Responder within that
system.

For most Bridges, the address of any MAC attached to the
Bridge will suffice for the low-order six octets, and 0 for
the high-order octets. In some situations, e.g., if multiple
virtual Bridges utilizing emulated LANs are implemented in a
single physical system, the high-order two octets can be
used to differentiate among the transmitting entities.

The value returned is undefined if the transmit-linktrace
input action was not accepted.";
                reference
                  "12.14.7.4.3c of IEEE Std 802.1Q-2021";

                uses ltm-egress-identifier-grouping;
              }  // container ltm-egress-identifier
            }
          }  // rpc transmit-linktrace
        }  // list mep
      }  // list maintenance-group
    }  // container cfm
  }  // module ieee802-dot1q-cfm