One document matched: draft-openconfig-rtgwg-network-instance-01.xml


<?xml version="1.0"?>
<!DOCTYPE rfc SYSTEM "rfc2629.dtd">
<rfc docName="draft-openconfig-rtgwg-network-instance-01" ipr="trust200902" category="info">
  <front>
    <title abbrev="Network Instance Model">A Data Model for Network Instances in Service Provider Networks</title>
    <!-- Include Rob Shakir as author -->
    <?rfc include="http://rob.sh/files/ietf-author.xml"?>
    <date month="November" year="2015" />

    <area>Routing</area>

    <abstract>
      <t>
          This document defines a YANG data model for configuring and
          managing forwarding instances on a network device - focused
          primarily on deployments in service provider networks. The
          model is vendor-neutral and based on operational
          requirements expressed by operators. A 'network instance' is
          defined to be a discrete forwarding table on a network
          element, which contains Layer 3 and/or Layer 2 forwarding
          entries. Each network instance may instantiate its own
          sets of protocols which control installation of
          forwarding entries into one or more tables (which may be
          Layer 2 FIBs, or Layer 3 RIBs).
      </t>
    </abstract>
  </front>

  <middle>
    <section title="Introduction" anchor="intro">
      <t>
          Within service provider networks, it is typical for a
          network element to maintain multiple forwarding tables,
          allowing the network to support multiple topologies. For
          instance, a service provider may offer Layer 2 or Layer 3
          VPN services to its customers - which requires a forwarding
          table per customer to be maintained on a network element. In
          other cases, multiple L3 services may be deployed to allow
          services such as Internet connectivity and private
          topologies to be maintained on a device.
      </t>
      <t>
          This <xref target="RFC6020">YANG</xref> data model defines a
          construct which can be used to configure and retrieve
          operational state related to such instances.
      </t>
      <section title="Goals and Approach" anchor="goals">
        <t>
            The concept of maintaining multiple Layer 2 virtual switch
            instances (VSIs) and/or multiple Layer 3 virtual routing
            and forwarding (VRF) tables is common on network elements
            that are deployed in service provider networks. However,
            within such networks there are requirements for a network
            instance to run both Layer 2 and Layer 3 routing
            protocols, or contain routed interfaces (e.g., a VPLS
            service where there is a Layer 3 interface within it, for
            subscriber termination or to act as a default gateway).
            For this reason, the intention of the model presented
            here is to define a generic construct which allows
            isolation of a forwarding table which may contain Layer 3
            RIB entries, Layer 2 FIB entries, or a combination both.
            This differs to the approach taken in other models, which
            tend to focus on solely L2 VSIs or L3 VRFs. An instance
            within the model is referred to as network instance - and
            may be configured to support L3 RIB entries only (i.e., be
            functionally equivalent to a VRF), L2 FIB entries only
            (i.e., act as a VSI) or support a combination of both.
        </t>
        <t>
            The model presented in this document is explicitly biased
            towards deployments on service provider network equipment,
            as discussed between members of the OpenConfig project.
        </t>
      </section>
    </section>
    <section title="Model overview" anchor="overview">
      <figure>
        <artwork>
module: openconfig-network-instance
   +--rw network-instances
      +--rw network-instance* [name]
         +--rw name                       -> ../config/name
         +--rw config
            ...
         +--ro state
            ...
         +--rw inter-instance-policies
         |  +--rw apply-policy
            ...
         +--rw table-connections
         |  +--rw table-connection* [src-table dst-table]
         |     +--rw src-table       -> ../config/src-table
         |     +--rw dst-table       -> ../config/dst-table
                ...
         |     +--rw apply-policy
                ...
         +--rw tables
         |  +--rw table* [table-name]
                ...
         +--rw interfaces
                ....
         +--rw connection-points
         |  +--rw connection-point* [connection-point-id]
              ...
         +--rw protocols
            +--rw protocol* [identifier name]
                ...
               +--rw static
                ...
               +--rw aggregate
                ...
        </artwork>
      </figure>
      <t>
        The key elements of the network instance model shown in
        the above outline tree view are:
        <list style='symbols'>
          <t>
            Type of network instance and key configuration parameters
            that relate to it (e.g., configuration of a route
            distinguisher for L3 routing instance).
          </t>
          <t>
            Policies which define how the instance exchanges routes
            with other instances - for example, allowing forwarding
            entries to be leaked between a global and private network
            instance.
          </t>
          <t>
            The individual tables that are maintained by a network
            instance. This caters for the approach whereby an
            implementation maintains per-protocol tables - and it is
            possible to examine these tables separately. The choice to
            implement this table definition is an open issue - as
            discussed in <xref target="rib-representation" />. Along
            with this table definition, a set of policies determining
            how entries are leaked between the tables is defined.
          </t>
          <t>
            Connections between the different tables that are
            maintained by the network instance. Where protocols
            populate individual tables, such connections facilitate
            leaking of routes between individual protocols (by means
            of populating entries from one into the table of the
            other).
          </t>
          <t>
            The interfaces associated with a certain network instance
            - the current implementation assumption (as demonstrated
            in the openconfig-interfaces models) is that configuration
            parameters that relate directly to the interface (e.g.,
            IP addressing) are configured directly under the interface
            construct. This requires that a network instance must have
            a means to be able to associate itself with an interface.
          </t>
          <t>
            A logical grouping of local or remote interfaces into
            'connection points' utilised by a number of Layer 2
            forwarding approaches (e.g., redundancy for attachment
            points for PWE or L2VPN services). This allows interfaces
            which are associated with the network instance to be
            associated with one another, and hence referenced as a
            group. This construct can be used to represent redundant
            interfaces for a P2P L2VPN - and is extensible to support
            Ethernet segments for other L2VPN types.
          </t>
          <t>
            A list of the protocols that are instantiated under the
            network instance. The protocols that are defined in <xref
            target='I-D.openconfig-rtgwg-local-routing' /> are
            included directly such that forwarding entries generated
            as static or aggregate routes can be matched in a routing
            policy. Other protocols, such as BGP (for which the data
            model is defined in <xref target='I-D.ietf-idr-bgp-model'
            /> would augment this list to include their own
            configuration options). It should be noted that the list
            of protocols is not keyed directly on the protocol name,
            but rather also includes an identifier for that instance.
            This supports cases where a single network instance may
            run multiple instances of a protocol.
          </t>
        </list>
      </t>
      <t>
        It is expected that all devices maintain at least one network
        instance, which represents the default (or global) forwarding
        table of the device. Additional instances are intended to
        support virtual instances, such as VSIs and VRFs.
      </t>
      <t>
        Where base configuration is required for such instances to be
        utilised (e.g., an route distinguisher value is required) then
        this is configured globally for each network instance. It
        expected that additional parameters, such as the encapsulation
        utilised for the instance will be added in future revisions of
        the model.
      </t>
      <t>
        Policies for leaking of routes between instances and tables
        leverage <xref target='I-D.ietf-rtgwg-policy-model' /> as a
        policy framework. This allows definition of 'import' policies
        (allowing a pull model) or export policies (allowing a push
        model) to be utilised for installation of entries into a local
        or remote network instance. The same framework is utilised to
        leak prefixes between multiple tables that are instantiated
        under an individual network instance.
      </t>
      <section title="Supporting Layer 2 Forwarding Constructs"
        anchor='l2forwarding'>
        <t>
          Whilst the initial focus of parameters in the
          model is to allow the instantiation of attributes related to
          Layer 3 forwarding constructs - it is expected that other
          configuration parameters, such as the definition of
          'cross-connections' between local and/or remote interfaces
          or connection points can be utilised to represent forwarding
          constructs within the network instance.
        </t>
        <t>
          The addition of this to the model is still a
          work-in-progress. The inclusion of the connection point
          configuration and state parameters is intended to
          demonstrate how L2 and L3 constructs can co-exist with one
          another within the model.
        </t>
      </section>
    </section>
    <section title="Open Issues" anchor="open-issues">
      <section title="Representation of per-protocol tables vs. a
        single table for all protocols" anchor="rib-representation">
        <t>
          Some implementations maintain a single table into which all
          protocols install entries. Each protocol is then configured
          to explicitly import entries from that table into their
          local 'export' table. Others maintain multiple RIBs and
          require explicit connections to be made between these tables
          such that entries from one protocol are made available to
          another.
        </t>
        <t>
          There are essentially two alternatives for how this is
          modelled in the network-instance model:
          <list style='numbers'>
            <t>
              Allow each protocol to specify a 'target-table' that
              indicates the table that its entries are to be installed
              into. In the case that the same target table is
              specified for multiple protocols, implicit import/export
              configuration between tables could be created on
              implementations that implement multiple RIBs. Explicit
              configuration can be utilised to explicitly allow an
              operator to leak between tables in the case that
              multiple target tables are specified. It should be noted
              that in fact, protocols that support multiple address
              families need to allow specification of the target table
              on a per-address-family basis.
            </t>
            <t>
              Assume that all protocols implement their own target
              tables. In this case, explicit configuration is utilised
              to leak between them. Implementations that do not
              support such per-protocol tables could implicitly
              generate the configuration that results in forwarding
              entries being leaked between the tables such that the
              appearance of a single target-table is maintained.
            </t>
          </list>
          As per the discussion in <xref target="overview" />
          currently,  this model chooses the former implementation
          approach.
        </t>
      </section>
    </section>
    <section title="Security Considerations">

      <t>
      Routing configuration has a significant impact on network operations,
      and as such any related model carries potential security risks.
      </t>

      <t>YANG data models are generally designed to be used with the
      NETCONF protocol over an SSH transport.  This provides an
      authenticated and secure channel over which to transfer
      configuration and operational data.  Note that use of
      alternate transport or data encoding (e.g., JSON over HTTPS)
      would require similar mechanisms for authenticating and
      securing access to configuration data.
      </t>

      <t>
        Most of the data elements in the network intsance model could
        be considered sensitive from a security standpoint.
        Unauthorized access or invalid data could cause major
        disruption.
      </t>

    </section>

    <section title="IANA Considerations">

      <t>
        This YANG data model and the component modules currently use a
      temporary ad-hoc namespace.  If and when it is placed on
      redirected for the standards track, an appropriate namespace URI
      will be registered in the <xref target="RFC3688">IETF XML
      Registry"</xref>. The routing policy YANG modules will be
      registered in the "YANG Module Names" registry [RFC6020].
      </t>
    </section>

    <section title="YANG module" anchor="models">

      <t>
        The network instance model is described by the YANG module
        below.
      </t>

   <figure>
	<artwork>
<![CDATA[
<CODE BEGINS> file openconfig-network-instance.yang

module openconfig-network-instance {

  yang-version "1";

  // namespace
  namespace "http://openconfig.net/yang/network-instance";

  prefix "netinst";

  // import some basic types
  //import ietf-inet-types { prefix inet; }
  import ietf-yang-types { prefix "yang"; }
  import ietf-inet-types { prefix "inet"; }
  import openconfig-network-instance-types { prefix "nit"; }
  import openconfig-policy-types { prefix "pt"; }
  import openconfig-routing-policy { prefix "rpol"; }
  import openconfig-local-routing { prefix "lroute"; }
  import openconfig-interfaces { prefix "ocif"; }
  import openconfig-extensions { prefix "ocext"; }

  // meta
  organization "OpenConfig working group";

  contact
    "OpenConfig working group
    www.openconfig.net";

  description
    "An OpenConfig description of a network-instance. This may be
    a Layer 3 forwarding construct such as a virtual routing and
    forwarding (VRF) instance, or a Layer 2 instance such as a
    virtual switch instance (VSI). Mixed Layer 2 and Layer 3
    instances are also supported.";

  ocext:openconfig-version "0.1.0";

  revision "2015-10-18" {
    description
      "Initial revision";
    reference "0.1.0";
  }

  grouping network-instance-top {
    description
      "Top-level grouping containing a list of network instances.";

  	container network-instances {
      description
        "The L2, L3, or L2+L3 forwarding instances that are
        configured on the local system";

  		list network-instance {
  			key "name";

        description
          "Network instances configured on the local system";

  			leaf name {
  				type leafref {
  					path "../config/name";
  				}
  				description
  					"A unique name identifying the network instance";
  			}

        container config {
          description
            "Configuration parameters relating to a network
            instance";
          uses network-instance-config;
          uses network-instance-l3vrf-config {
            when "../type = 'L3VRF'" {
              description
                "Layer 3 VRF configuration parameters included when a
                network instance is of type L3VRF";
            }
          }
        }
        container state {
          config false;
          description
            "Operational state parameters relating to a network
            instance";
          uses network-instance-config;
          uses network-instance-l3vrf-config {
            when "../type = 'L3VRF'" {
              description
                "Layer 3 VRF configuration parameters included when a
                network instance is of type L3VRF";
            }
          }
          uses network-instance-state;
        }

        container inter-instance-policies {
          description
            "Policies dictating how RIB or FIB entries are imported
            to and exported from this instance";

          uses rpol:apply-policy-group;
        }

        container table-connections {
          description
            "Policies dictating how RIB or FIB entries are propagated
            between tables";

          list table-connection {
            key "src-table dst-table";

            description
              "A list of connections between pairs of routing or
              forwarding tables, the leaking of entries between
              which is specified by the import and export policy";

            leaf src-table {
              type leafref {
                path "../config/src-table";
              }
              description
                "The name of the table which should be utilised
                as the source of forwarding or routing information";
            }

            leaf dst-table {
              type leafref {
                path "../config/dst-table";
              }
              description
                "The table to which routing entries should be
                exported";
            }

            container config {
              description
                "Configuration parameters relating to the connection
                between tables";
              uses inter-table-policies-config;
            }
            container state {
              config false;
              description
                "State parameters relating to the connection between
                tables";
              uses inter-table-policies-config;
            }

            uses rpol:apply-policy-group;
          }
        }

        container tables {
          description
            "The routing tables that are managed by this network
            instance";

          list table {
            key "table-name";

            description
              "A network instance manages one or more forwarding or
              routing tables. These may reflect the Layer 2
              forwarding information base, the Layer 3 routing
              information base of the MPLS LFIB. Protocols may be
              explictly associated with a particular table into
              which they populate entries. Multiple protocols may
              install entries into a single table, or there may be a
              1:1 relationship between a routing protocol and a
              table .The import-policy and export-policy lists are
              used to specify how routes leak between different
              tables within the same forwarding instance.";

            leaf table-name {
              type leafref {
                path "../config/table-name";
              }
              description
                "A name for the table";
            }

            container config {
              description
                "Configuration parameters related to the table";
              uses table-config;
            }

            container state {
              config false;
              description
                "State parameters related to the table";
              uses table-config;
            }
          }
        }

        container interfaces {
          description
            "Interfaces associated with this network intance";

          container config {
            description
              "Configuration parameters relating to interfaces
              associated with the instance";
            uses instance-interfaces-config;
          }
          container state {
            config false;
            description
              "State parameters relating to interfaces associated
              with the instance";
            uses instance-interfaces-config;
            uses instance-interfaces-state;
          }
        }

        container connection-points {
          description
            "The set of connection points within a forwarding
            instance";

          list connection-point {
            key "connection-point-id";

            description
              "A connection point within a Layer 2 network instance.
              Each connection-point consists of a set of interfaces
              only one of which is active at any one time. Other than
              the specification of whether an interface is local
              (i.e., exists within this network-instance), or remote,
              all configuration and state parameters are common";

            leaf connection-point-id {
              type leafref {
                path "../config/connection-point-id";
              }
              description
                "A locally significant reference for the
                connection-point";
            }

            container config {
              description
                "Configuration parameters relating to a Layer 2
                network instance connection point";
              uses instance-connection-point-config;
            }
            container state {
              config false;
              description
                "Operational state parameters relating to a Layer 2
                network instance connection point";

              uses instance-connection-point-config;
              uses instance-connection-point-state;
            }

            container endpoints {
              when "../config/type = 'L2P2P' " +
                 "or ../config/type = 'L2VSI'" {
                description
                  "Configuration parameters to associate interfaces
                   into a common group for use in Layer 2 network
                   instances";
              }

              description
                "The set of endpoints which are grouped within the
                connection point";

              list endpoint {
                key "endpoint-id";

                description
                  "A list of the endpoints (interfaces or remote
                  connection points that can be used for this
                  connection point). The active endpoint is selected
                  based on the precedence that it is configured
                  with";

                leaf endpoint-id {
                  type leafref {
                    path "../config/endpoint-id";
                  }
                  description
                    "A pointer to the configured identifier for the
                    endpoint";
                }

                container config {
                  description
                    "Configuration parameters relating to the
                    endpoint";
                  uses instance-endpoint-config;
                }
                container state {
                  config false;
                  description
                    "Operational state parameters relating to the
                    endpoint";
                  uses instance-endpoint-config;
                  uses instance-endpoint-state;
                }
              }
            }
          }
        }

        container protocols {
          description
            "The routing protocols that are enabled for this
            network-instance.";

          list protocol {
            key "identifier name";

            description
              "A process (instance) of a routing protocol. Some
              systems may not support more than one instance of
              a particular routing protocol";

            leaf identifier {
              type leafref {
                path "../config/identifier";
              }
              description
                "The protocol name for the routing or forwarding
                protocol to be instantiated";
            }

            leaf name {
              type leafref {
                path "../config/name";
              }
              description
                "An operator-assigned identifier for the routing
                or forwarding protocol. For some processes this
                leaf may be system defined.";
            }

            container config {
              description
                "Configuration parameters relating to the routing
                protocol instance";

              uses protocols-config;
            }

            container state {
              config false;
              description
                "State parameters relating to the routing protocol
                instance";

              uses protocols-config;
              uses protocols-state;
            }

            container static {
              when "../config/identifier = 'STATIC'" {
                description
                  "Include static route parameters only when the
                  protocol is set to static";
              }
              description
                "Configuration and state parameters relating to
                static routes";
              uses lroute:local-static-top;
            }

            container aggregate {
              when "../config/identifier = 'LOCAL-AGGREGATE'" {
                description
                  "Include aggregate route parameters only when the
                  protocol is set to aggregate";
              }
              description
                "Configuration and state parameters relating to
                locally generated aggregate routes";
              uses lroute:local-aggregate-top;
            }
          }
        }
  		}
  	}
  }

  grouping instance-endpoint-config {
    description
      "Configuration data relating to an forwarding-instance
      endpoint";

    leaf endpoint-id {
      type string;
      description
        "An identifier for the endpoint";
    }

    uses instance-endpoint-local-remote;

    leaf precedence {
      type uint16;
      description
        "The precedence of the endpoint - the lowest precendence
        viable endpoint will be utilised as the active endpoint
        within a connection";
    }
  }

  grouping instance-endpoint-local-remote {
    description
      "A generic specification of a local or remote endpoint";

    choice local-remote {
      case local {
        leaf interface {
          type leafref {
            path "/network-instances/network-instance" +
                 "/interfaces/config/interface";
          }
          description
            "Reference to the local interface that is a member of
            the forwarding-instance";
        }
      }
      case remote {
        leaf neighbor {
          type inet:ip-address;
          description
            "The IP address of the device which hosts the
            remote end-point";
        }

        leaf virtual-circuit-identifier {
          type uint32;
          description
            "The virtual-circuit identifier that identifies the
            connection at the remote end-point";
        }
      }
      description
        "Configuration relating to an endpoint which can either be
        local (an interface), or remote. In the case where it is
        remote a neighbor IP address and virtual-circuit identifier
        must be specified";
    }
  }

  grouping instance-endpoint-state {
    description
      "Operational state data relating to a forwarding-instance
      endpoint";
    leaf active {
      type boolean;
      description
        "When the backup endpoint is active, the value of this
        parameter is set to true";
    }
  }

  grouping instance-connection-point-config {
    description
      "Configuration data relating to a forwarding-instance
      connection point";

    leaf connection-point-id {
      type string;
      description
        "An identifier for a connection point";
    }
  }

  grouping instance-connection-point-state {
    description
      "Operational state data relating to a forwarding-instance
      connection point";
  }

  grouping table-config {
    description
      "Configuration parameters relating to a L2/L2.5/L3 table that
      exists within the network instance";

    leaf table-name {
      type string;
      description
        "A human-readable name for the table";
    }

  }

  grouping table-state {
    description
      "State parameters relating to a table - this may be
      utilised to store generic structure for retrieving the contents
      of a RIB, FIB or LFIB";
    // placeholder
  }

  grouping inter-table-policies-config {
    description
      "Configuration entries that relate to how RIB or FIB entries
      are propagated between tables within the same network
      instance";

    leaf src-table {
      type leafref {
        // we are at table-connections/table-connection/config/.
        path "../../../../tables/table/table-name";
      }
      description
        "The source protocol for the table connection";
    }

    leaf dst-table {
      type leafref {
        path "../../../../tables/table/table-name";
      }
      description
        "The destination protocol for the table connection";
    }


  }

  grouping network-instance-config {
    description
      "Configuration parameters relating to a top-level network
      instance";

    leaf name {
      type string;
      description
        "An operator-assigned unique name for the forwarding
        instance";
    }

    leaf type {
      type identityref {
        base "nit:network-instance-type";
      }
      description
        "The type of network instance. The value of this leaf
        indicates the type of forwarding entries that should be
        supported by this network instance";
    }

    leaf enabled {
      type boolean;
      description
        "Whether the network instance should be configured to be
        active on the network element";
    }

    leaf description {
      type string;
      description
        "A free-form string to be used by the network operator to
        describe the function of this network instance";
    }

    leaf router-id {
      type yang:dotted-quad;
      description
        "A identifier for the local network instance - typically
        used within associated routing protocols or signalling
        routing information in another network instance";
    }

    leaf route-distinguisher {
      type nit:route-distinguisher;
      description
        "The route distinguisher that should be used for the local
        VRF or VSI instance when it is signalled via BGP.";
    }
  }

  grouping network-instance-state {
    description
      "Operational state parameters relating to a network instance";
  }

  grouping network-instance-l3vrf-config {
    description
      "Configuration parameters for a network instance of type
      l3vrf";

  }

  grouping protocols-config {
    description
      "Configuration parameters relating to a generic protocol
      instance within a network instance";

    leaf identifier {
      type identityref {
        base "pt:install-protocol-type";
      }
      description
        "The protocol identifier for the instance";
    }

    leaf name {
      type string;
      description
        "A unique name for the protocol instance";
    }

    leaf enabled {
      type boolean;
      description
        "A boolean value indicating whether the local protocol
        instance is enabled.";
    }

    leaf target-table {
     type leafref {
      path "../../../../tables/table/table-name";
     }
     description
      "The table (RIB, FIB, or LFIB) that the protocol should
      populate its entries in.";
    }
  }

  grouping protocols-state {
    description
      "Operational state parameters relating to a protocol instance";
  }

  grouping instance-interfaces-config {
    description
      "Base configuration parameters relating to the interfaces
      associated with a network instance";

    leaf-list interface {
      type leafref {
        path "/ocif:interfaces/ocif:interface/ocif:name";
      }
      description
        "Interfaces that are associated with the network instance";
    }
  }

  grouping instance-interfaces-state {
    description
      "State parameters relating to the interfaces associated with a
      network instance";
  }

  uses network-instance-top;

}

<CODE ENDS>
]]>
    </artwork>
  </figure>

  <figure>
    <artwork><![CDATA[
<CODE BEGINS> file openconfig-network-instance-types.yang

module openconfig-network-instance-types {

  yang-version "1";

  // namespace
  namespace "http://openconfig.net/yang/network-instance-types";

  prefix "nit";

  import openconfig-extensions { prefix "ocext"; }

  // meta
  organization "OpenConfig working group";

  contact
    "OpenConfig working group
    www.openconfig.net";

  description
    "Types associated with a network instance";

  ocext:openconfig-version "0.1.0";

  revision "2015-10-18" {
    description
      "Initial revision";
    reference "0.1.0";
  }

  // identity statements
  identity network-instance-type {
  	description
  	 "A base identity which can be extended to indicate different
     types of network instance supported by a device.";
  }

  identity DEFAULT-INSTANCE {
    base network-instance-type;
    description
      "A special routing instance which acts as the 'default' or
      'global' routing instance for a network device.";
  }

  identity L3VRF {
    base network-instance-type;
    description
      "A private Layer 3 only routing instance which is formed of
      one or more RIBs";
  }

  identity L2VSI {
    base network-instance-type;
    description
      "A private Layer 2 only switch instance which is formed of
      one or more L2 forwarding tables";
  }

  identity L2P2P {
    base network-instance-type;
    description
      "A private Layer 2 only forwarding instance which acts as
      a point to point connection between two endpoints";
  }

  identity L2L3 {
    base network-instance-type;
    description
      "A private Layer 2 and Layer 2 forwarding instance";
  }

  // rjs note:
  // this should move to openconfig-types when merged
  typedef route-distinguisher {
    type union {
      // type 0: <2-byte administrator>:<4-byte assigned number>
      type string {
        pattern "(65[0-5][0-3][0-5]|[1-5][1-5][0-9][0-9][0-9]|"
                + "[1-9]?[1-9]?[0-9][0-9]|[1-9]):"
                + "(4[0-2][0-9][0-4][0-9][0-6][0-7][0-2][0-9][0-5]|"
                + "[0-3][0-9]{9}|[1-9][0-9]{1,8}|[1-9])";
      }
      // type 1: <ip-address>:<2-byte assigned number>
      type string {
        pattern
          "(([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.){3}"
          +  "([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5]):"
          +  "(65[0-5][0-3][0-5]|[1-5][1-5][0-9][0-9][0-9]|"
          +  "[1-9]?[1-9]?[0-9][0-9]|[1-9])";
      }
      // type 2: <4-byte as-number>:<2-byte assigned number>
      type string {
        pattern
          "(4[0-2][0-9][0-4][0-9][0-6][0-7][0-2][0-9][0-5]|"
          + "[0-3][0-9]{9}|[1-9][0-9]{1,8}|[1-9]):"
          + "65[0-5][0-3][0-5]|[1-5]{2}[0-9]{3}|"
          + "[1-9]{0,2}[0-9][0-9]|[1-9])";
      }
    }
    description "A route distinguisher value";
    reference "RFC4364";
  }

}

<CODE ENDS>
      ]]>
    </artwork>
  </figure>
    </section>
  </middle>

  <back>
    <references title="Normative references">
      <?rfc include="http://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.6020" ?>
      <?rfc include="http://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.3688" ?>
      <?rfc include="http://xml2rfc.ietf.org/public/rfc/bibxml3/reference.I-D.openconfig-rtgwg-local-routing" ?>
      <?rfc include="http://xml2rfc.ietf.org/public/rfc/bibxml3/reference.I-D.ietf-rtgwg-policy-model"?>
      <?rfc include="http://xml2rfc.ietf.org/public/rfc/bibxml3/reference.I-D.ietf-idr-bgp-model" ?>
    </references>
    <references title="Informative references">
      <reference anchor="YANG-REPO"
        target="https://github.com/openconfig/public/releases/network-instance">
        <front>
          <title>OpenConfig YANG Data Model Repository -
            Network Instance</title>
          <author></author>
          <date month="November" year="2015" />
        </front>
      </reference>
    </references>

    <section title="Acknowledgements">
      <t>TODO
      </t>
    </section>
  </back>
</rfc>

PAFTECH AB 2003-20262026-04-23 14:16:51