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submodule etsi-nfv-vnf {
  belongs-to etsi-nfv {
    prefix nfv;
  }

  import ietf-inet-types {
    prefix inet;
  }
  import ietf-yang-types {
    prefix yang;
  }
  import etsi-nfv-common {
    prefix common;
  }
  include etsi-nfv-ns;

  description
    "Models for VNFD according to GS NFV-IFA 011.";

  revision 2018-06-19 {
    description
      "Initial revision.

       Common data structure to support VNFD according to:
       VNFD according to ETSI GS NFV-IFA 011 Ed251v243";
      "ETSI GS NFV-IFA 011 Ed251v243";
  }

  grouping virtual-network-interface-requirements {
    list virtual-network-interface-requirement {
      key "name";
      description
        "Specifies requirements on a virtual network interface
         realising the CPs instantiated from this CPD.";
      reference
        "GS NFV-IFA011: Section 7.1.6.4, VduCpd information
         element";

      leaf name {
        type string;
        description
          "Provides a human readable name for the requirement.";
        reference
          "GS NFV-IFA011: Section 7.1.6.6,
           VirtualNetworkInterfaceRequirements information element";
      }
      leaf description {
        type string;
        description
          "Provides a human readable description of the requirement.";
        reference
          "GS NFV-IFA011: Section 7.1.6.6,
           VirtualNetworkInterfaceRequirements information element";
      }
      leaf support-mandatory {
        mandatory true;
        type boolean;
        description
          "Indicates whether fulfilling the constraint is
           mandatory (true) for successful operation or desirable
           (false).";
        reference
          "GS NFV-IFA011: Section 7.1.6.6,
           VirtualNetworkInterfaceRequirements information element";
      }
      list network-interface-requirements {
        key "key";
        leaf key {
          type string;
        }
        leaf value {
          type string;
        }
        description
          "The network interface requirements. An element from an
           array of key-value pairs that articulate the network
           interface deployment requirements.";
        reference
          "GS NFV-IFA011: Section 7.1.6.6,
           VirtualNetworkInterfaceRequirements information element";
      }
      leaf niclo-requirements {
        mandatory true;
        type string; // remove once leafref is resolved.
        //type leafref {
          // add path statement here to logical-node-data.
        //}
        description
          "This references (couples) the CPD with any logical node I/O
           requirements (for network devices) that may have been
           created. Linking these attributes is necessary so that so
           that I/O requirements that need to be articulated at the
           logical node level can be associated with the network
           interface requirements associated with the CPD.";
        reference
          "GS NFV-IFA011: Section 7.1.6.6,
           VirtualNetworkInterfaceRequirements information element";
      }
    }
  }

  grouping vnfd {
    list vnfd {
      key "id";
      description
        "A VNF Descriptor (VNFD) is a deployment template which
         describes a VNF in terms of deployment and operational
         behaviour requirements. It also contains connectivity,
         interface and virtualised resource requirements";
      reference
        "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      leaf id {
        type string;
        description
          "Identifier of this VNFD information element. This attribute
           shall be globally unique. The format will be defined in the
           data model specification phase.";
        reference
          "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      }
      leaf provider {
        type string;
        mandatory true;
        description
          "Provider of the VNF and of the VNFD";
        reference
          "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      }
      leaf product-name {
        type string;
        mandatory true;
        description
          "Name to identify the VNF Product. Invariant for the VNF
           Product lifetime.";
        reference
          "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      }
      leaf software-version {
        type string;
        mandatory true;
        description
          "Software version of the VNF. This is changed when there is
           any change to the software that is included in the VNF
           Package";
        reference
          "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      }
      leaf version {
        type string;
        mandatory true;
        description
          "Identifies the version of the VNFD";
        reference
          "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      }
      leaf product-info-name {
        type string;
        description
          "Human readable name of the VNFD. Can change
           during the VNF Product lifetime.";
        reference
          "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      }
      leaf product-info-description {
        type string;
        description
          "Human readable description of the VNFD. Can change during
           the VNF Product lifetime.";
        reference
          "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      }
      leaf-list vnfm-info {
        type string;
        min-elements 1;
        description
          "Identifies VNFM(s) compatible with the VNF described in
           this version of the VNFD.";
        reference
          "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      }
      leaf localization-language {
        type string;
        description
          "Information about the language of the VNF.";
        reference
          "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      }
      leaf default-localization-language {
        when "../localization-language";
        type string;
        description
          "Default localization language that is instantiated if no
           information about selected localization language is
           available. Shall be present if 'localization-language'
           is present and shall be absent otherwise.";
        reference
          "GS NFV-IFA011: Section 7.1.2, VNFD information element";
      }
      list vdu {
        key "id";
        min-elements 1;
        description
          "The Virtualisation Deployment Unit (VDU) is a construct supporting
           the description of the deployment and operational behaviour of a
           VNF component, or the entire VNF if it was not componentized in
           components.";
        reference
          "GS NFV IFA011: Section 7.1.2, VNFD information element";
        leaf id {
          type string;
          description
            "Unique identifier of this VDU in VNFD.";
          reference
            "GS NFV IFA011: Section 7.1.6.2, Vdu information element";
        }
        leaf name {
          type string;
          mandatory true;
          description
            "Human readable name of the VDU.";
          reference
            "GS NFV IFA011: Section 7.1.6.2, Vdu information element";
        }
        leaf description {
          type string;
          description
            "Human readable description of the VDU.";
          reference
            "GS NFV IFA011: Section 7.1.6.2, Vdu information element";
        }
        list int-cpd {
          key "id";
          min-elements 1;
          description
            "A internal-connection-point element is a type of
             connection point and describes network connectivity
             between a VDU instance and an internal Virtual Link or
             an external connection point.";
          reference
            "GS NFV IFA011: Section 7.1.6.2, Vdu information element";
          choice cp-connection {
            mandatory true;
            description
              "A connection point must either connect to an internal
               virtual link or to an external connection points.";
            leaf int-virtual-link-desc {
              type leafref {
                path "../../../nfv:int-virtual-link-desc/nfv:id";
              }
              description
                "Reference of the internal VLD which this internal CPD
                 connects to.";
              reference
                "GS NFV IFA011: Section 7.1.6.4, VduCpd information
                 element";
            }
            leaf ext-cpd {
              description
                "Connect to an external connection point";
              type leafref {
                path "../../../nfv:ext-cpd/nfv:id";
              }
            }
          }
          leaf bitrate-requirement {
            type uint64;
            units "Mbps";
            description
              "Bitrate requirement on this CP.";
            reference
              "GS NFV IFA011: Section 7.1.6.4, VduCpd information
               element.";
          }
          uses virtual-network-interface-requirements;
          leaf-list order {
            type uint32;
            description
              "The order of the NIC to be assigned on the compute
               instance (e.g. 2 for eth2).

               Note: when binding more than one port to a single
               compute (aka multi vNICs) and ordering is desired, it
               is mandatory that all ports will be set with an order
               value. The order values shall represent a positive,
               arithmetic progression that starts with 0 (i.e. 0, 1,
               2,..., n).

               If the property is not present, it shall be left to the
               VIM to assign a value when creating the instance.";
            reference
              "GS NFV IFA011: Section 7.1.6.4, VduCpd information
               element.";
          }
          uses common:cpd;
        }
        leaf virtual-compute-desc {
          type leafref {
            path "../../nfv:virtual-compute-descriptor/" +
                 "nfv:id";
          }
          description
            "Describes CPU, Memory and acceleration requirements of
             the Virtualisation Container realizing this VDU.";
          reference
            "GS NFV IFA011: Section 7.1.6.2, VDU information
             element, and Section 7.1.9.2.2, VirtualComputeDesc
             information element.";
        }
        leaf-list virtual-storage-desc {
          type leafref {
            path "../../nfv:virtual-storage-descriptor/" +
                 "nfv:id";
          }
          description
            "Describes storage requirements for a VirtualStorage
             instance attached to the virtualisation container
             created from virtualComputeDesc defined for this VDU.";
          reference
            "GS NFV IFA011: Section 7.1.6.2, VDU information
             element, and Section 7.1.9.4, Information elements
             related to Virtual Storage.";
        }
        list boot-order {
          ordered-by user;
          key "key";
          leaf key {
            type uint32;
          }
          leaf value {
            type leafref {
              path "../../nfv:virtual-storage-desc";
            }
          }
          description
            "The key indicates the boot index (lowest index defines
             highest boot priority). The Value references a descriptor
             from which a valid boot device is created e.g.
             VirtualStorageDesc from which a VirtualStorage instance
             is created.

             Editor's note: The boot-order node requires further
             study.";
          reference
            "GS NFV IFA011: Section 7.1.6.2, Vdu information
             element.";
        leaf sw-image-desc {
          type leafref {
            path "../../sw-image-desc/id";
          }
          description
            "Describes the software image which is directly loaded on
             the virtualisation container realising this Vdu.";
          reference
            "GS NFV IFA011: Section 7.1.6.2, Vdu information
             element.";
        }
        leaf-list nfvi-constraint {
          type string;
          description
            "Describes constraints on the NFVI for the VNFC
             instance(s) created from this Vdu. For example, aspects
             of a secure hosting environment for the VNFC instance
             that involve additional entities or processes.";
          reference
            "GS NFV IFA011: Section 7.1.6.2, VDU Information
             element.";
        }
        list monitoring-parameter {
          key "id";
          leaf id {
            type string;
            description
              "Unique identifier of the monitoring parameter.";
            reference
              "GS NFV IFA011: Section 7.1.11.3, MonitoringParameter
               information element.";
          }
          uses common:monitoring-parameter;
        list configurable-properties {
          key "key";
          leaf key {
            type string;
          }
          leaf value {
            type string;
          }
          description
            "It provides VNFC configurable properties that can be
             modified using the ModifyVnfInfo operation.";
            "GS NFV IFA011: Section 7.1.6.7,
             VnfcConfigurableProperties Information element.";
        }
        list boot-data {
          key "key";
          leaf key {
            type string;
            type string;
          }
          description
            "Contains a string or a URL to a file contained in the
             VNF package used to customize a virtualised compute
             resource at boot time. The bootData may contain variable
             parts that are replaced by deployment specific values
             before being sent to the VIM.";
          reference
            "GS NFV IFA011: Section 7.1.6.7,
             VnfcConfigurableProperties Information element.";
      list virtual-compute-descriptor {
        key "id";
        description
          "Defines descriptors of virtual compute resources to be
           used by the VNF.";
        leaf id {
          type string;
          description
            "Unique identifier of this VirtualComputeDesc in the
             VNFD.";
          reference
            "GS NFV IFA011: Section 7.1.9.2, Information elements
             related to Virtual CPU.";
        }

        list logical-node {
          key "key";
          leaf key {
            type string;
          }
          leaf value {
            type string;
          }
          description
            "The logical Node requirements.";
          reference
            "GS NFV IFA011: Section 7.1.9.2.2, VirtualComputeDesc
             information element.";
        }

        list request-additional-capability {
          key "name";
          leaf name {
            type string;
            description
              "Identifies a requested additional capability for the
               VDU. ETSI GS NFV-IFA 002 [i.1] describes acceleration
               capabilities.";
            reference
              "GS NFV IFA011: Section 7.1.9.5,
               RequestedAdditionalCapabilityData Information
               element.";
          }
          leaf support-mandatory {
            type boolean;
            description
              "Indicates whether the requested additional capability
               is mandatory for successful operation.";
            reference
              "GS NFV IFA011: Section 7.1.9.5,
               RequestedAdditionalCapabilityData Information
               element.";
          }

          leaf min-version {
            type string;
            description
              "Identifies the minimum version of the requested
               additional capability.";
            reference
              "GS NFV IFA011: Section 7.1.9.5,
               RequestedAdditionalCapabilityData Information
               element.";
          }

          leaf preferred-version {
            type string;
            description
              "Identifies the preferred version of the requested
               additional capability.";
            reference
              "GS NFV IFA011: Section 7.1.9.5, 
               RequestedAdditionalCapabilityData Information
               element.";
          }
          list target-performance-parameters {
            key "key";
            leaf key {
              type string;
            }
            leaf value {
              type string;
            }
            description
              "Identifies specific attributes, dependent on the 
               requested additional capability type.";
            reference
              "GS NFV IFA011: Section 7.1.9.5, 
               RequestedAdditionalCapabilityData Information
               element.";
          }
        }

        leaf compute-requirements {
          type string;
          description
            "Specifies compute requirements.";
          reference
            "GS NFV IFA011: Section 7.1.9.2.2, VirtualComputeDesc
             Information element.";
        }

        container virtual-memory {
          leaf size {
            type decimal64 {
              fraction-digits 1;
              range "0..max";
            }
            must ". >= ../../../sw-image-desc[id=current()]/min-ram";
            units "Gb";
            mandatory true;
            description
              "Amount of virtual memory in MB.";
            reference
              "GS NFV IFA011: Section 7.1.9.3, Information elements
               related to Virtual Memory.";
          }
          leaf over-subscription-policy {
            type string;
            description
              "The memory core oversubscription policy in terms of
               virtual memory to physical memory on the platform.
               The cardinality can be 0 during the allocation
               request, if no particular value is requested.";
            reference
              "GS NFV IFA011: Section 7.1.9.3, Information elements
               related to Virtual Memory.";
          }
          list vdu-mem-requirements {
            key "key";
            leaf key {
              type string;
            }
            leaf value {
              type string;
            }
            description
              "Array of key-value pair requirements on the memory for
               the VDU.";
            reference
              "GS NFV IFA011: Section 7.1.9.3.2, VirtualMemoryData
               information element.";
          }

          leaf numa-enabled {
            type boolean;
            description
              "It specifies the memory allocation to be cognisant of
               the relevant process/core allocation. The cardinality
               can be 0 during the allocation request, if no
               particular value is requested.";
            reference
              "GS NFV IFA011: Section 7.1.9.3, Information elements
               related to Virtual Memory.";
          }
          description
            "The virtual memory of the virtualised compute.";
          reference
            "GS NFV IFA011: Section 7.1.9.2.2, VirtualComputeDesc
             Information element.";
        }
        container virtual-cpu {
          description
            "The virtual CPU(s)of the virtualised compute.";
          reference
            "GS NFV IFA011: Section 7.1.9.2.2, VirtualComputeDesc
             Information element.";

          leaf cpu-architecture {
            type string;
            description
              "CPU architecture type. Examples are x86, ARM. The
               cardinality can be 0 during the allocation request,
               if no particular CPU architecture type is requested.";
            reference
              "GS NFV IFA011: Section 7.1.9.2.3, VirtualCpuData
               information elements.";
          }
          leaf num-virtual-cpu {
            type uint16 {
              range "1..max";
            }
            mandatory true;
            description
              "Number of virtual CPUs.";
            reference
              "GS NFV IFA011: Section 7.1.9.2.3, VirtualCpuData
               information elements.";
          }
          leaf clock {
            type uint32;
            units "MHz";
            description
              "Minimum virtual CPU clock rate (e.g. in MHz). The
               cardinality can be 0 during the allocation request,
               if no particular value is requested.";
            reference
              "GS NFV IFA011: Section 7.1.9.2.3, VirtualCpuData
               information elements.";
          }
          leaf oversubscription-policy {
            type string;
            description
              "The CPU core oversubscription policy e.g. the relation
               of virtual CPU cores to physical CPU cores/threads.
               The cardinality can be 0 during the allocation request,
               if no particular value is requested.";
            reference
              "GS NFV IFA011: Section 7.1.9.2.3, VirtualCpuData
               information elements.";
          }
          list vdu-cpu-requirements {
            key "key";
            leaf key {
              type string;
            }
            leaf value {
              type string;
            }
            description
              "Array of key-value pair requirements on the compute
               (CPU) for the VDU.";
            reference
              "GS NFV IFA011: Section 7.1.9.3.2, VirtualCpuData
               information element.";
          }
          container virtual-cpu-pinning {
            presence "Set to specify CPU pinning.";
            leaf cpu-pinning-policy {
              mandatory true;
              type enumeration {
                enum "static";
                enum "dynamic";
              }
              description
                "Indicates the policy for CPU pinning. The policy can
                 take values of 'static' or 'dynamic'. The cardinality
                 can be 0 during the allocation request, if no
                 particular value is requested.";
            }
            container cpu-pinning-map {
              when "../nfv:cpu-pinning-policy = 'static'";
            }
            description
              "If cpuPinningPolicy is defined as 'static', the
               cpuPinningMap provides the map of pinning virtual
               CPU cores to physical CPU cores/threads. Cardinality
               is 0 if cpuPinningPolicy has a different value than
               'static'.";
          }
        }
      }
      list virtual-storage-descriptor {
        key "id";
        description
          "Storage requirements for a Virtual Storage instance
           attached to the VNFC created from this VDU";
        leaf id {
          type string;
          description
            "Unique identifier of this VirtualStorageDesc in the
             VNFD.";
          reference
            "GS NFV IFA011: Section 7.1.9.4, Information elements
             related to Virtual Storage.";
        }

        leaf type-of-storage {
          // Needed to be able to onboard images
          type enumeration {
            enum "root";
            enum "swap";
            enum "ephemeral";
          }
          mandatory true;
          description
            "Type of virtualised storage resource (e.g. volume,
             object).";
          reference
            "GS NFV IFA011: Section 7.1.9.4, Information elements
             related to Virtual Storage.";
        }
        leaf size-of-storage {
          must ". >= ../../sw-image-desc[id=current()]/min-disk";

          type uint64;
          units "Gb";
          mandatory true;
          description
            "Size of virtualised storage resource (e.g. size of
             volume, in Gb)";
            "GS NFV IFA011: Section 7.1.9.4, Information elements
             related to Virtual Storage.";
        }
        list vdu-storage-requirements {
          key "key";
          leaf key {
            type string;
          }
          leaf value {
            type string;
          }
          description
            "Array of key-value pairs that articulate the storage
             deployment requirements.";
          reference
            "GS NFV IFA011: Section 7.1.9.4.2, VirtualStorageDesc
             information element.";
        }
        leaf rdma-enabled {
          type boolean;
          description
            "Indicate if the storage support RDMA.";
          reference
            "GS NFV IFA011: Section 7.1.9.4, Information elements
             related to Virtual Storage.";
        }
        leaf sw-image-desc {
          type leafref {
            path "../../sw-image-desc/id";
          }
          description
            "Software image to be loaded on the VirtualStorage
             resource created based on this VirtualStorageDesc.";
          reference
            "GS NFV IFA011: Section 7.1.9.4, Information elements
             related to Virtual Storage.";
        }
      }
      container sw-image-desc {
        description
          "Defines descriptors of software images to be used by the
           VNF.";
        reference
          "GS NFV IFA011: Section 7.1.2, VNFD Information element.";
        leaf id {
          type string;
          description
            "The identifier of this software image.";
          reference
            "GS NFV IFA011: Section 7.1.6.5, SwImageDesc
             information element";
        }
        leaf name {
          type string;
          description
            "The name of this software image.";
          reference
            "GS NFV IFA011: Section 7.1.6.5 SwImageDesc
             information element.";
        }
        leaf version {
          type string;
          description
            "The version of this software image.";
          reference
            "GS NFV IFA011: Section 7.1.6.5 SwImageDesc
             information element.";
        }
        leaf checksum {
          type string;
          description
            "The checksum of the software image file.";
          reference
            "GS NFV IFA011: Section 7.1.6.5 SwImageDesc
             information element.";
        }
        leaf container-format {
          mandatory true;
          type enumeration {
            enum "aki" {
              description
                "An Amazon kernel image.";
            }
            enum "ami" {
              description
                "An Amazon machine image.";
            }
            enum "ari" {
              description
                "An Amazon ramdisk image.";
            }
            enum "bare" {
              description
                "The image does not have a container or metadata
                 envelope.";
            }
            enum "docker" {
              description
                "A docker container format.";
            }
            enum "ova" {
              description
                "An OVF package in a tarfile.";
            }
            enum "ovf" {
              description
                "The OVF container format.";
            }
          }
          description
            "The container format describes the container file
             format in which software image is provided.";
          reference
            "GS NFV IFA011: Section 7.1.6.5 SwImageDesc
             information element.";
        }
        leaf disk-format {
          mandatory true;
          type enumeration {
            enum "aki" {
              description
                "An Amazon kernel image.";
            }
            enum "ami" {
              description
                "An Amazon machine image.";
            }
            enum "ari" {
              description
                "An Amazon ramdisk image.";
            }
            enum "iso" {
              description
                "An archive format for the data contents of an
                 disk, such as CD-ROM.";
            }
            enum "qcow2" {
              description
                "Supported by the QEMU emulator that can expand
                 dynamically and supports Copy on Write.";
            }
            enum "raw" {
              description
                "An unstructured disk image format; if you have a
                 file without an extension it is possibly a raw
                 format.";
            }
            enum "vdi" {
              description
                "Supported by VirtualBox virtual machine monitor
                 and the QEMU emulator.";
            }
            enum "vhd" {
              description
                "The VHD disk format, a common disk format used by
                 virtual machine monitors from VMware, Xen,
                 Microsoft, VirtualBox, and others.";
            }
            enum "vhdx" {
              description
                "The VHDX disk format, an enhanced version of the
                 VHD format, which supports larger disk sizes among
                 other features.";
            }
            enum "vmdk" {
              description
                "Common disk format supported by many common virtual
                 machine monitors.";
            }
          }
          description
            "The disk format of a software image is the format of
             the underlying disk image.";
        }
        leaf min-disk {
          type uint64;
          units "Gb";
          description
            "The minimal disk size requirement for this software
             image. The value of the 'size of storage' attribute
             of the VirtualStorageDesc referencing this
             SwImageDesc shall not be smaller than the value of
             minDisk.";
          reference
            "GS NFV IFA011: Section 7.1.6.5, SwImageDesc
             information element.";
        }
        leaf min-ram {
          type decimal64 {
            fraction-digits 1;
            range "0..max";
          }
          units "Gb";
          description
            "The minimal RAM requirement for this software image.
             The value of the 'size' attribute of
             VirtualMemoryData of the Vdu referencing this
             SwImageDesc shall not be smaller than the value of
             minRam.";
          reference
            "GS NFV IFA011: Section 7.1.6.5, SwImageDesc
             information element.";
        }
        leaf size {
          type uint64;
          units "Gb";
          description
            "The size of this software image.";
          reference
            "GS NFV IFA011: Section 7.1.6.5, SwImageDesc
             information element.";
        }
        leaf image {
          mandatory true;
          type inet:uri;
          description
            "This is a reference to the actual software image.
             The reference can be relative to the root of the VNF
             Package or can be a URL";
          reference
            "GS NFV IFA011: Section 7.1.6.5, SwImageDesc
             information element.";
        }
        leaf operating-system {
          type string;
          description
            "Identifies the operating system used in the software
             image. This attribute may also identify if a 32 bit
             or 64 bit software image is used.";
          reference
            "GS NFV IFA011: Section 7.1.6.5, SwImageDesc
             information element.";
        }
        leaf-list supported-virtualization-environment {
          type string;
          description
            "Identifies the virtualisation environments
             (e.g. hypervisor) compatible with this software
             image.";
          reference
            "GS NFV IFA011: Section 7.1.6.5, SwImageDesc
             information element.";
        }
      }

      list int-virtual-link-desc {
        key "id";
        description
          "Represents the type of network connectivity mandated by the
           VNF provider between two or more CPs which includes at
           least one internal CP.";
        reference
          "GS NFV IFA011: Section 7.1.2, Vnfd information element.";
        leaf id {
          type string;
          description
            "Unique identifier of this internal VLD in VNFD.";
          reference
            "GS NFV IFA011: Section 7.1.7.2, VnfVirtualLinkDesc
             Information elements.";
        }

        list desc-flavor {
          key "id";
          description
            "Describes a specific flavour of the VL with specific
             bitrate requirements.";
          reference
            "GS NFV IFA011: Section 7.1.7.2, VnfVirtualLinkDesc
             Information elements.";

          leaf id {
            type string;
            description
              "Identifies a flavour within a VnfVirtualLinkDesc.";
            reference
              "GS NFV IFA011: Section 7.1.8.5, VirtualLinkDescFlavor
               information element.";
          }
          container qos {
            description
              "QoS of the VL.";
            reference
              "GS NFV IFA011: Section 7.1.8.5, VirtualLinkDescFlavor
               information element.";

            leaf latency {