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Versions: (draft-zhuang-bess-l3vpn-yang) 00 01 draft-ietf-bess-l3vpn-yang

Network Working Group                                              Z. Li
Internet-Draft                                                 S. Zhuang
Intended status: Standards Track                     Huawei Technologies
Expires: June 23, 2016                                            X. Liu
                                                                Ericsson
                                                                 J. Haas
                                                                S. Esale
                                                        Juniper Networks
                                                                  B. Wen
                                                                 Comcast
                                                       December 21, 2015


                  Yang Data Model for BGP/MPLS IP VPN
                      draft-li-bess-l3vpn-yang-01

Abstract

   This document defines a YANG data model that can be used to configure
   and manage L3VPN (BGP/MPLS IP VPN).

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on June 23, 2016.








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Copyright Notice

   Copyright (c) 2015 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Definitions and Acronyms  . . . . . . . . . . . . . . . . . .   3
   3.  Design of the L3VPN Model . . . . . . . . . . . . . . . . . .   3
     3.1.  Overview  . . . . . . . . . . . . . . . . . . . . . . . .   3
     3.2.  VPN Instance Configuration  . . . . . . . . . . . . . . .   4
       3.2.1.  Per-Instance Configuration  . . . . . . . . . . . . .   4
       3.2.2.  Address Family Configuration of L3VPN Instance  . . .   4
     3.3.  Yang Tree of L3VPN Yang Model . . . . . . . . . . . . . .   5
   4.  L3VPN YANG Model  . . . . . . . . . . . . . . . . . . . . . .   7
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  15
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  15
   7.  Normative References  . . . . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16

1.  Introduction

   YANG [RFC6020] is a data definition language that was introduced to
   define the contents of a conceptual data store that allows networked
   devices to be managed using NETCONF [RFC6241].  YANG is proving
   relevant beyond its initial confines, as bindings to other interfaces
   (e.g.  ReST) and encodings other than XML (e.g.  JSON) are being
   defined.  Furthermore, YANG data models can be used as the basis of
   implementation for other interfaces, such as CLI and programmatic
   APIs.

   This document defines a YANG data model that can be used to configure
   and manage L3VPN (BGP/MPLS IP VPN) [RFC4364].







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2.  Definitions and Acronyms

   AF: Address Family

   BGP: Border Gateway Protocol

   JSON: JavaScript Object Notation

   L3VPN: Layer 3 VPN

   NETCONF: Network Configuration Protocol

   ReST: Representational State Transfer, a style of stateless interface
   and protocol that is generally carried over HTTP

   YANG: A data definition language for NETCONF

3.  Design of the L3VPN Model

3.1.  Overview

   The L3VPN Yang module is to augment the routing instance Yang models
   proposed by the draft [I-D.ietf-netmod-routing-cfg].  It introduced
   the "l3vpn"container to define augmented parameters which can be
   applied for VRF Routing Instance and support both the IPv4 and IPv6
   address families.  The overview of the "l3vpn" container is shown in
   the following figure:

   module: ietf-l3vpn
   augment /rt:routing/rt:routing-instance:
      +--rw l3vpn
         +--rw ipv4-family
         |  +--rw bgp-parameters
         |  |  +--rw common
         |  |     +--rw route-distinguisher?   string
         |  |     +--rw vpn-targets* [rt-value]
         |  |        +--rw rt-value    string
         |  |        +--rw rt-type     bgp-rt-type
         |  ......
         +--rw ipv6-family
            +--rw bgp-parameters
            |  +--rw common
            |     +--rw route-distinguisher?   string
            |     +--rw vpn-targets* [rt-value]
            |        +--rw rt-value    string
            |        +--rw rt-type     bgp-rt-type
            ......




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   L3VPN inteface parameters can reuse those parameters defined by
   [I-D.ietf-netmod-routing-cfg].

   BGP Protocols parameters for L3VPN is defined by the draft
   [I-D.ietf-idr-bgp-model].  The augment may be defined in the future
   version if necessary.

3.2.  VPN Instance Configuration

   An instance is created to comprise the VPN forwarding information for
   each VPN in a BGP/MPLS IP VPN.  This instance is called a VPN
   instance or a VPN routing and forwarding (VRF) table.  It is also
   called a per-site forwarding table in [RFC4364].  VPN instances must
   be created in all BGP/MPLS IP VPN solutions.  VPN instances support
   both the IPv4 and IPv6 address families.

   VPN instance configuration consists of the following components :

   o Per-Instance Configuration : that contains the common writable
   configuration objects for VPN instance IPv4 and IPv6 address family.

   o Address Family Configuration of L3VPN Instance: that contains the
   address family specific writable configuration objects.

3.2.1.  Per-Instance Configuration

   Per-instance parameters is defined by [I-D.ietf-netmod-routing-cfg]
   including instance name, description, etc.

3.2.2.  Address Family Configuration of L3VPN Instance

   l3vpn container contains the address family specific writable
   configuration objects, such as route-distinguisher, vpn-targets,
   apply-label-mode, etc.  The parameters should be consistent between
   IPv4 family and IPv6 family.
















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      +--rw l3vpn
         +--rw ipv4-family
         |  +--rw bgp-parameters
         |  |  +--rw common
         |  |     +--rw route-distinguisher?   string
         |  |     +--rw vpn-targets* [rt-value]
         |  |        +--rw rt-value    string
         |  |        +--rw rt-type     bgp-rt-type
         |  +--rw apply-label-mode?      apply-label-mode-def
         |  +--rw import-route-policy?   string
         |  +--rw export-route-policy?   string
         |  +--rw tunnel-policy?         string
         |  +--rw prefix-limit
         |  |  +--rw prefix-limit-number?   uint32
         |  |  +--rw (prefix-limit-action)?
         |  |     +--:(enable-alert-percent)
         |  |     |  +--rw alert-percent-value?   uint8
         |  |     |  +--rw route-unchanged?       boolean
         |  |     +--:(enable-simple-alert)
         |  |        +--rw simple-alert?          boolean
         |  +--rw routing-table-limit
         |  |  +--rw routing-table-limit-number?   uint32
         |  |  +--rw (routing-table-limit-action)?
         |  |     +--:(enable-alert-percent)
         |  |     |  +--rw alert-percent-value?          uint8
         |  |     +--:(enable-simple-alert)
         |  |        +--rw simple-alert?                 boolean
         |  +--rw import-global-rib
         |     +--rw protocol?            enumeration
         |     +--rw processId?           uint32
         |     +--rw bgp-valid-route?     boolean
         |     +--rw route-policy-name?   string
         +--rw ipv6-family
            ......

3.3.  Yang Tree of L3VPN Yang Model

   The Yang tree of L3VPn Yang model is shown in the following figure:

   module: ietf-l3vpn
   augment /rt:routing/rt:routing-instance:
      +--rw l3vpn
         +--rw ipv4-family
         |  +--rw bgp-parameters
         |  |  +--rw common
         |  |     +--rw route-distinguisher?   string
         |  |     +--rw vpn-targets* [rt-value]
         |  |        +--rw rt-value    string



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         |  |        +--rw rt-type     bgp-rt-type
         |  +--rw apply-label-mode?      apply-label-mode-def
         |  +--rw import-route-policy?   string
         |  +--rw export-route-policy?   string
         |  +--rw tunnel-policy?         string
         |  +--rw prefix-limit
         |  |  +--rw prefix-limit-number?   uint32
         |  |  +--rw (prefix-limit-action)?
         |  |     +--:(enable-alert-percent)
         |  |     |  +--rw alert-percent-value?   uint8
         |  |     |  +--rw route-unchanged?       boolean
         |  |     +--:(enable-simple-alert)
         |  |        +--rw simple-alert?          boolean
         |  +--rw routing-table-limit
         |  |  +--rw routing-table-limit-number?   uint32
         |  |  +--rw (routing-table-limit-action)?
         |  |     +--:(enable-alert-percent)
         |  |     |  +--rw alert-percent-value?          uint8
         |  |     +--:(enable-simple-alert)
         |  |        +--rw simple-alert?                 boolean
         |  +--rw import-global-rib
         |     +--rw protocol?            enumeration
         |     +--rw processId?           uint32
         |     +--rw bgp-valid-route?     boolean
         |     +--rw route-policy-name?   string
         +--rw ipv6-family
            +--rw bgp-parameters
            |  +--rw common
            |     +--rw route-distinguisher?   string
            |     +--rw vpn-targets* [rt-value]
            |        +--rw rt-value    string
            |        +--rw rt-type     bgp-rt-type
            +--rw apply-label-mode?      apply-label-mode-def
            +--rw import-route-policy?   string
            +--rw export-route-policy?   string
            +--rw tunnel-policy?         string
            +--rw prefix-limit
            |  +--rw prefix-limit-number?   uint32
            |  +--rw (prefix-limit-action)?
            |     +--:(enable-alert-percent)
            |     |  +--rw alert-percent-value?   uint8
            |     |  +--rw route-unchanged?       boolean
            |     +--:(enable-simple-alert)
            |        +--rw simple-alert?          boolean
            +--rw routing-table-limit
            |  +--rw routing-table-limit-number?   uint32
            |  +--rw (routing-table-limit-action)?
            |     +--:(enable-alert-percent)



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            |     |  +--rw alert-percent-value?          uint8
            |     +--:(enable-simple-alert)
            |        +--rw simple-alert?                 boolean
            +--rw import-global-rib
               +--rw protocol?            enumeration
               +--rw processId?           uint32
               +--rw bgp-valid-route?     boolean
               +--rw route-policy-name?   string

4.  L3VPN YANG Model

   //L3VPN YANG MODEL
   <CODE BEGINS> file "ietf-l3vpn.yang"
   module ietf-l3vpn {
     namespace "urn:ietf:params:xml:ns:yang:ietf-l3vpn";
     // replace with IANA namespace when assigned
     prefix "l3vpn";

     import ietf-routing {
       prefix "rt";
       //draft-ietf-netmod-routing-cfg-19
     }

     organization  "IETF BGP Enabled Services WG";
     contact       "draft-li-bess-l3vpn-yang@tools.ietf.org";
     description
       "This YANG module defines the generic configuration data
        for L3VPN service.

        Terms and Acronyms

        BGP (bgp): Border Gateway Protocol
        IPv4 (ipv4):Internet Protocol Version 4
        IPv6 (ipv6): Internet Protocol Version 6

       ";

     revision 2015-10-09 {
       description
         "Initial revision.";
         reference "RFC4271, RFC4364, RFC4365, RFC4760.";
     }

     /* typedefs */

     typedef bgp-rt-type {
       type enumeration {
         enum import {



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           description "For import";
         }
         enum export {
           description "For export";
         }
         enum both {
           description "For both import and export";
         }
       }
       description "BGP route-target type. Import from BGP YANG.";
     }

     typedef apply-label-mode-def {
       type enumeration {
         enum "per-route" {
           value 0;
           description
             "By default, the VPN instance IPv4 address family
              assigns a unique label to each route to be sent
              to the peer PE.";
         }
         enum "per-instance" {
           value 1;
           description
             "The apply-label per-instance command enables the
              one-label-per-VPN-instance mode.";
         }
       }
       description "...";
     }

     typedef routing-instance-type-ref {
       type leafref {
         path "/rt:routing/rt:routing-instance/rt:type";
       }
       description
         "This type is used for leafs that reference a routing
          instance configuration.";
     }

     grouping bgp-parameters-grp {
       description
         "BGP parameters grouping.";
       container bgp-parameters {
         description
           "Parameters for BGP.";
         container common {
           description



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             "Common BGP parameters.";
           leaf route-distinguisher {
             type string;
             description "BGP RD.";
           }
           list vpn-targets {
             key rt-value;
             description
               "Route Targets.";
             leaf rt-value {
               type string;
               description
                 "Route-Target value.";
             }
             leaf rt-type {
               type bgp-rt-type;
               mandatory true;
               description
                 "Type of RT.";
             }
           }
         }
       }
     }


     grouping vpn-af-config {
       description
         "A set of configuration parameters that is applicable to both
          IPv4 and IPv6 address family for a VPN instance .";

       leaf apply-label-mode {
         type apply-label-mode-def;
         default "per-route";
         description ".";
       }

       leaf import-route-policy {
         type string {
           length "1..40";
         }
         description
           "The import route-policy command associates a VPN instance
            enabled with the IPv4 or IPv6 address family with an
            import routing policy.
            Only one import routing policy can be associated with a
            VPN instance enabled with the IPv4 or IPv6 address family.
            If the import route-policy command is run more than once,



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            the latest configuration overrides the previous ones.";
       }

       leaf export-route-policy {
         type string {
           length "1..40";
         }
         description
           "The export route-policy command associates a VPN instance
            enabled with the IPv4 or IPv6 address family with an
            export routing policy.
            Only one export routing policy can be associated with a
            VPN instance enabled with the IPv4 or IPv6 address family.
            If the export route-policy command is run more than once,
            the latest configuration overrides the previous ones.";
       }

       leaf tunnel-policy {
          type string;
          description
            "Tunnel policy name.";
       }

       container prefix-limit {
         description
           "The prefix limit command sets a limit on the maximum
            number of prefixes supported in the existing VPN
            instance, preventing the PE from importing excessive
            VPN route prefixes.";

         leaf prefix-limit-number {
           type uint32 {
             range "1..4294967295";
           }
           description
             "Specifies the maximum number of prefixes supported in the
              VPN instance IPv4 or IPv6 address family.";
         }

         choice prefix-limit-action {
           description ".";
           case enable-alert-percent {
             leaf alert-percent-value {
               type uint8 {
                 range "1..100";
               }
               description
                 "Specifies the proportion of the alarm threshold to the



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                  maximum number of prefixes.";
             }
             leaf route-unchanged {
               type boolean;
               default "false";
               description
                 "Indicates that the routing table remains unchanged.
                  By default, route-unchanged is not configured. When
                  the number of prefixes in the routing table is
                  greater than the value of the parameter number,
                  routes are processed as follows:
                  (1)If route-unchanged is configured, routes in the
                     routing table remain unchanged.
                  (2)If route-unchanged is not configured, all routes
                     in the routing table are deleted and then
                     re-added.";
             }
           }
           case enable-simple-alert {
             leaf simple-alert {
               type boolean;
               default "false";
               description
                 "Indicates that when the number of VPN route prefixes
                  exceeds number, prefixes can still join the VPN
                  routing table and alarms are displayed.";
             }
           }
         }
       }


       container routing-table-limit {
         description
           "The routing-table limit command sets a limit on the maximum
            number of routes that the IPv4 or IPv6 address family of a
            VPN instance can support.
            By default, there is no limit on the maximum number of
            routes that the IPv4 or IPv6 address family of a VPN
            instance can support, but the total number of private
            network and public network routes on a device cannot
            exceed the allowed maximum number of unicast routes.";

         leaf routing-table-limit-number {
           type uint32 {
             range "1..4294967295";
           }
           description



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             "Specifies the maximum number of routes supported by a
              VPN instance. ";
         }

         choice routing-table-limit-action {
           description ".";
           case enable-alert-percent {
             leaf alert-percent-value {
               type uint8 {
                 range "1..100";
               }
               description
                 "Specifies the percentage of the maximum number of
                  routes. When the maximum number of routes that join
                  the VPN instance is up to the value
                  (number*alert-percent)/100, the system prompts
                  alarms. The VPN routes can be still added to the
                  routing table, but after the number of routes
                  reaches number, the subsequent routes are
                  dropped.";
             }
           }
           case enable-simple-alert {
             leaf simple-alert {
               type boolean;
               description
                 "Indicates that when VPN routes exceed number, routes
                  can still be added into the routing table, but the
                  system prompts alarms.
                  However, after the total number of VPN routes and
                  network public routes reaches the unicast route limit
                  specified in the License, the subsequent VPN routes
                  are dropped.";
             }
           }
         }
       }

       container import-global-rib {
         description
           "Route Leaking from a Global Routing Table into a VRF.";

         leaf protocol {
           type enumeration {
             enum ALL {
               value "0";
               description "ALL:";
             }



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             enum Direct {
               value "1";
               description "Direct:";
             }
             enum OSPF {
               value "2";
               description "OSPF:";
             }
             enum ISIS {
               value "3";
               description "ISIS:";
             }
             enum Static {
               value "4";
               description "Static:";
             }
             enum RIP {
               value "5";
               description "RIP:";
             }
             enum BGP {
               value "6";
               description "BGP:";
             }
             enum OSPFV3 {
               value "7";
               description "OSPFV3:";
             }
             enum RIPNG {
               value "8";
               description "RIPNG:";
             }
             enum INVALID {
               value "9";
               description "INVALID:";
             }
           }
           description
             "Specifies the protocol from which routes are imported.
              At present, In the IPv4 unicast address family view,
              the protocol can be IS-IS,static, direct and BGP.";
         }

         leaf processId {
           type uint32 {
             range "0..4294967295";
           }
           default "0";



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           description
             "Specifies the process ID if the protocol from routes
              are imported is IS-IS.";
         }

         leaf bgp-valid-route {
           type boolean;
           description ".";
         }

         leaf route-policy-name {
           type string;
           description
             "Policy Id for import routes";
         }

       }
     }

     augment "/rt:routing/rt:routing-instance" {
       description ".";
       container l3vpn {
         when "routing-instance-type-ref = 'vrf-routing-instance'" {
           description ".";
         }
         description ".";
         container ipv4-family {
           description
             "The IPv4 address family is enabled for the VPN
              instance.";

           uses bgp-parameters-grp;
           uses vpn-af-config;
         }

         container ipv6-family {
           description
             "The IPv6 address family is enabled for the VPN
              instance.";

           uses bgp-parameters-grp;
           uses vpn-af-config;
         }
       } //End of case type

     } //End of augment "/rt:routing/rt:routing-instance"

   }



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   </CODE ENDS>


5.  IANA Considerations

   This document makes no request of IANA.

6.  Security Considerations

   This document does not introduce any new security risk.

7.  Normative References

   [I-D.ietf-idr-bgp-model]
              Shaikh, A., Shakir, R., Patel, K., Hares, S., D'Souza, K.,
              Bansal, D., Clemm, A., Alex, A., Jethanandani, M., and X.
              Liu, "BGP Model for Service Provider Networks", draft-
              ietf-idr-bgp-model-00 (work in progress), July 2015.

   [I-D.ietf-netmod-routing-cfg]
              Lhotka, L. and A. Lindem, "A YANG Data Model for Routing
              Management", draft-ietf-netmod-routing-cfg-20 (work in
              progress), October 2015.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC4271]  Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
              Border Gateway Protocol 4 (BGP-4)", RFC 4271,
              DOI 10.17487/RFC4271, January 2006,
              <http://www.rfc-editor.org/info/rfc4271>.

   [RFC4364]  Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
              Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February
              2006, <http://www.rfc-editor.org/info/rfc4364>.

   [RFC4760]  Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
              "Multiprotocol Extensions for BGP-4", RFC 4760,
              DOI 10.17487/RFC4760, January 2007,
              <http://www.rfc-editor.org/info/rfc4760>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <http://www.rfc-editor.org/info/rfc6020>.




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   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <http://www.rfc-editor.org/info/rfc6241>.

Authors' Addresses

   Zhenbin Li
   Huawei Technologies
   Huawei Bld., No.156 Beiqing Rd.
   Beijing  100095
   China

   Email: lizhenbin@huawei.com


   Shunwan Zhuang
   Huawei Technologies
   Huawei Bld., No.156 Beiqing Rd.
   Beijing  100095
   China

   Email: zhuangshunwan@huawei.com


   Xufeng Liu
   Ericsson
   1595 Spring Hill Road, Suite 500
   Vienna, VA  22182
   USA

   Email: xufeng.liu@ericsson.com


   Jeffrey Haas
   Juniper Networks

   Email: jhaas@juniper.net


   Santosh Esale
   Juniper Networks
   1194 N. Mathilda Ave.
   Sunnyvale, CA  94089
   US

   Email: sesale@juniper.net




Li, et al.                Expires June 23, 2016                [Page 16]


Internet-Draft          Yang Data Model for L3VPN          December 2015


   Bin Wen
   Comcast

   Email: Bin_Wen@cable.comcast.com















































Li, et al.                Expires June 23, 2016                [Page 17]


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