[Docs] [txt|pdf|xml|html] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

Versions: (draft-boucadair-softwire-dslite-yang) 00 01 02 03 04 05 06 07

Network Working Group                                       M. Boucadair
Internet-Draft                                              C. Jacquenet
Intended status: Standards Track                                  Orange
Expires: April 12, 2018                                     S. Sivakumar
                                                           Cisco Systems
                                                         October 9, 2017


                   YANG Data Modules for the DS-Lite
                   draft-ietf-softwire-dslite-yang-07

Abstract

   This document defines YANG modules for the DS-Lite Address Family
   Transition Router (AFTR) and Basic Bridging BroadBand (B4) elements .

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 https://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 April 12, 2018.

Copyright Notice

   Copyright (c) 2017 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
   (https://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.




Boucadair, et al.        Expires April 12, 2018                 [Page 1]


Internet-Draft                DS-Lite YANG                  October 2017


Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   4
   2.  DS-Lite YANG Modules: An Overview . . . . . . . . . . . . . .   4
   3.  DS-Lite AFTR YANG Module  . . . . . . . . . . . . . . . . . .   7
   4.  DS-Lite B4 YANG Module  . . . . . . . . . . . . . . . . . . .  13
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  16
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  16
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  17
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  17
     8.1.  Normative references  . . . . . . . . . . . . . . . . . .  17
     8.2.  Informative references  . . . . . . . . . . . . . . . . .  18
   Appendix A.  Examples . . . . . . . . . . . . . . . . . . . . . .  20
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  21

1.  Introduction

   This document defines data models for DS-Lite [RFC6333], using the
   YANG data modeling language [RFC7950].  Both the Address Family
   Transition Router (AFTR) and Basic Bridging BroadBand (B4) elements
   are covered by this specification.  As a reminder, Figure 1
   illustrates an overview of the DS-Lite architecture that involves
   AFTR and B4 elements.



























Boucadair, et al.        Expires April 12, 2018                 [Page 2]


Internet-Draft                DS-Lite YANG                  October 2017


                      +-----------+
                      |    Host   |
                      +-----+-----+
                            |10.0.0.1
                            |
                            |
                            |10.0.0.2
                  +---------|---------+
                  |         |         |
                  |    Home router    |
                  |+--------+--------+|
                  ||       B4        ||
                  |+--------+--------+|
                  +--------|||--------+
                           |||2001:db8:0:1::1
                           |||
                           |||<-IPv4-in-IPv6 softwire
                           |||
                    -------|||-------
                  /        |||        \
                 |   ISP core network  |
                  \        |||        /
                    -------|||-------
                           |||
                           |||2001:db8:0:2::1
                  +--------|||--------+
                  |        AFTR       |
                  |+--------+--------+|
                  ||   Concentrator  ||
                  |+--------+--------+|
                  |       |NAT|       |
                  |       +-+-+       |
                  +---------|---------+
                            |192.0.2.1
                            |
                    --------|--------
                  /         |         \
                 |       Internet      |
                  \         |         /
                    --------|--------
                            |
                            |198.51.100.1
                      +-----+-----+
                      | IPv4 Host |
                      +-----------+

                    Figure 1: DS-Lite Base Architecture




Boucadair, et al.        Expires April 12, 2018                 [Page 3]


Internet-Draft                DS-Lite YANG                  October 2017


   DS-Lite deployment considerations are discussed in [RFC6908].

   This document follows the guidelines of [RFC6087], uses the common
   YANG types defined in [RFC6991], and adopts Network Management
   Datastore Architecture (NMDA).

1.1.  Terminology

   This document makes use of the terms defined in Section 3 of
   [RFC6333].

   The terminology for describing YANG data modules is defined in
   [RFC7950].

   The meaning of the symbols in tree diagrams is defined in
   [I-D.ietf-netmod-yang-tree-diagrams].

2.  DS-Lite YANG Modules: An Overview

   As shown in Figure 1:

   o  The AFTR element is a combination of an IPv4-in-IPv6
      encapsualtion/decapsulation function and a NAT function.

   o  The B4 element is an IPv4-in-IPv6 encapsulation function.

   Therefore, the AFTR YANG module is designed to augment both the
   Interfaces YANG module [RFC7223] and the NAT YANG module
   [I-D.ietf-opsawg-nat-yang] with DS-Lite specific features.  The B4
   YANG module augments the interfaces YANG module.

   Concretely, the AFTR YANG module (Figure 2) augments the Interfaces
   YANG module with the following:

   o  An IPv6 address used by the AFTR for sending and receiving IPv4-
      in-IPv6 packets (aftr-ipv6-address).

   o  An IPv4 address that is used by the AFTR for troubleshooting
      purposes (aftr-ipv4-address): According to [RFC6333], that address
      can be used to report ICMP problems and will appear in traceroute
      outputs.

   o  The tunnel MTU to avoid fragmentation (tunnel-mtu): Since using an
      IPv4-in-IPv6 encapsulation to carry IPv4 traffic over IPv6 reduces
      the effective MTU of the datagram, operators should be able to
      increase the MTU size by at least 40 bytes to accommodate both the
      IPv6 encapsulation header and the IPv4 datagram without
      fragmenting the IPv6 packet (Section 2.2 of [RFC6908]).



Boucadair, et al.        Expires April 12, 2018                 [Page 4]


Internet-Draft                DS-Lite YANG                  October 2017


   o  A policy to limit the number of DS-Lite softwires per subscriber
      (max-softwire-per-subscriber): This policy aims to prevent a
      misbehaving subscriber from mounting several DS-Lite softwires
      that would consume additional AFTR resources (e.g., get more
      external ports if the quota were enforced on a per-softwire basis,
      consume extra processing due to a large number of active
      softwires) [RFC7785].

   o  A DSCP marking policy to be followed when encapsulating/
      decapsulating packets (v6-v4-dscp-preservation): Section 2.10 of
      [RFC6908] discusses the uniform model which assumes that
      implementations of this model copy the DSCP value to the outer IP
      header at encapsulation and copy the outer header's DSCP value to
      the inner IP header at decapsulation.  Operators should configure
      the AFTR so that it copies the DSCP value in the IPv4 header to
      the Traffic Class field in the IPv6 header, and vice versa.

   In addition, the AFTR YANG module augments the NAT YANG module (nat-
   policy, in particular) with the following:

   o  A policy to instruct the AFTR whether a state can be automatically
      migrated (state-migrate): This policy avoids stale mappings at the
      AFTR and minimizes the risk of service disruption for subscribers.
      According to [RFC7785], the AFTR should migrate existing state to
      be bound to the new IPv6 address in the event a new IPv6 address
      is assigned to the B4 element.  This operation ensures that
      traffic destined to the previous B4's IPv6 address will be
      redirected to the newer B4's IPv6 address.

   o  An instruction to rewrite the TCP Maximum Segment Size (MSS)
      option (mss-clamping) to avoid TCP fragmentation.

   Given that the NAT44 table of the AFTR element is extended to include
   the source IPv6 address of incoming packets, the AFTR YANG module
   augments the NAT mapping-entry with the following:

   o  b4-ipv6-address which is used to record the source IPv6 address of
      a packet received from a B4 element.  This IPv6 address is
      required to disambiguate between the overlapping IPv4 address
      space of customers.

   o  The value of the Traffic Class field in the IPv6 header as
      received from a B4 element (v6-dscp): This information is used to
      preserve DSCP marking when encapsulating/decapsulationg at the
      AFTR.






Boucadair, et al.        Expires April 12, 2018                 [Page 5]


Internet-Draft                DS-Lite YANG                  October 2017


   o  The IPv4 DSCP marking of the IPv4 packet received from a B4
      element (internal-v4-dscp): This information can be used by the
      AFTR fro enforcing the poi

   o  The IPv4 DSCP marking as set by the AFTR in its external interface
      (external-v4-dscp): An AFTR can be instructed to preserve the same
      marking or to set it to another value when forwarding an IPv4
      packet upstream.

module: ietf-dslite-aftr
  augment /if:interfaces/if:interface:
    +--rw aftr-ipv6-address?             inet:ipv6-address
    +--rw aftr-ipv4-address?             inet:ipv4-address
    +--rw tunnel-mtu?                    uint16
    +--rw max-softwire-per-subscriber?   uint8
    +--rw v6-v4-dscp-preservation?       boolean
  augment /nat:nat-module/nat:nat-instances/nat:nat-instance/nat:nat-policy:
    +--rw state-migrate?   boolean
    +--rw mss-clamping
       +--rw mss-clamping-enable?   boolean
       +--rw mss-value?             uint16
  augment /nat:nat-module/nat:nat-instances/nat:nat-instance/nat:mapping-table/nat:mapping-entry:
    +--rw b4-ipv6-address?    inet:ipv6-address
    +--rw v6-dscp?            uint8
    +--rw internal-v4-dscp?   uint8
    +--rw external-v4-dscp?   uint8

                  Figure 2: YANG Module for DS-Lite AFTR

   Examples to illustrate the use of this module are provided in
   Appendix A.

   The B4 YANG module (Figure 3) augments the Interfaces YANG module
   with the following:

   o  An IPv6 address used by a B4 element for sending and receiving
      IPv4-in-IPv6 packets (b4-ipv6-address).

   o  The IPv6 address of the AFTR to use by a B4 element (aftr-
      ipv6-addr).

   o  An IPv4 address that is used by a B4 element for troubleshooting
      purposes (b4-ipv4-address).

   o  The tunnel MTU at the B4 side to avoid fragmentation (tunnel-mtu).






Boucadair, et al.        Expires April 12, 2018                 [Page 6]


Internet-Draft                DS-Lite YANG                  October 2017


   o  An instruction whether DSCP marking is to preserved when
      encapsulating an IPv4 packet in an IPv6 packet (v6-v4-dscp-
      preservation).

   module: ietf-dslite-b4
     augment /if:interfaces/if:interface:
       +--rw b4-ipv6-address?           inet:ipv6-address
       +--rw aftr-ipv6-addr?            inet:ipv6-address
       +--rw b4-ipv4-address?           inet:ipv4-address
       +--rw tunnel-mtu?                uint16
       +--rw v6-v4-dscp-preservation?   boolean

                   Figure 3: YANG Module for DS-Lite B4

   PCP-related considerations are out of scope of the document.  A YANG
   module for PCP is documented in [I-D.boucadair-pcp-yang].

3.  DS-Lite AFTR YANG Module

<CODE BEGINS> file "ietf-dslite-aftr@2017-10-09.yang"

module ietf-dslite-aftr {
    yang-version 1.1;

    namespace "urn:ietf:params:xml:ns:yang:ietf-dslite-aftr";
    prefix dslite-aftr;

    import ietf-inet-types { prefix inet; }
    import ietf-interfaces { prefix if; }
    import iana-if-type { prefix ianaift; }
    import ietf-nat {prefix nat;}

    organization "Softwire Working Group";
    contact
     "Mohamed Boucadair <mohamed.boucadair@orange.com>
      Christian Jacquenet <christian.jacquenet@orange.com>
      Senthil Sivakumar <ssenthil@cisco.com>";

   description
      "This module is a YANG module for DS-Lite AFTR
      implementations.

      Copyright (c) 2017 IETF Trust and the persons identified as
      authors of the code.  All rights reserved.

      Redistribution and use in source and binary forms, with or
      without modification, is permitted pursuant to, and subject
      to the license terms contained in, the Simplified BSD License



Boucadair, et al.        Expires April 12, 2018                 [Page 7]


Internet-Draft                DS-Lite YANG                  October 2017


      set forth in Section 4.c of the IETF Trust's Legal Provisions
      Relating to IETF Documents
      (http://trustee.ietf.org/license-info).

      This version of this YANG module is part of RFC XXXX; see
      the RFC itself for full legal notices.";

    revision 2017-10-09 {
      description "Early yangdoctors review.";
      reference "-ietf-07";
    }

    revision 2017-08-10 {
      description "The module augments also the Interface module.";
      reference "-ietf-04";
    }

    revision 2017-07-27 {
      description "Redesign the module as an augment of the NAT YANG module.";
      reference "-ietf-04";
    }

    revision 2017-07-03 {
      description "Fix some minor points.";
      reference "-ietf-03";
    }

    revision 2017-01-03 {
      description "Fixed a compilation error:
        https://github.com/mbj4668/pyang/issues/296.";
      reference "-ietf-02";
    }

    revision 2016-11-14 {
      description "Integrates the comments from Ian:
      add B4 module, add an MSS leaf, add more details about
      logging protocols, and other edits.";
      reference "-ietf-01";
    }

    revision 2016-07-27 {
      description "-00 IETF version.";
      reference "-ietf-00";
    }

    revision 2016-06-13 {
      description "Update the module.";
      reference "-04";



Boucadair, et al.        Expires April 12, 2018                 [Page 8]


Internet-Draft                DS-Lite YANG                  October 2017


    }

    revision 2015-12-16 {
      description "Fix an error.";
      reference "-03";
    }

    revision 2015-09-01 {
      description "Add port threshold notifications.";
      reference "-02";
    }

    revision 2015-08-31 {
      description "Fix a timeout issue.";
      reference "-01";
    }

    revision 2015-08-17 {
      description "First spec.";
      reference "-00";
    }

// Augment Interface module with DS-Lite Softwire

augment "/if:interfaces/if:interface" {
   when "if:type = 'ianaift:tunnel'";

   description
     "Augments Interface module with AFTR parameters.
      IANA interface types are maintained at this registery:
      https://www.iana.org/assignments/ianaiftype-mib/ianaiftype-mib.

        tunnel (131),       -- Encapsulation interface";

   leaf aftr-ipv6-address {
         type inet:ipv6-address;

         description
            "IPv6 address of the DS-Lite AFTR.";

         reference
            "RFC 6333.";
        }

    leaf aftr-ipv4-address {
        type inet:ipv4-address;
        default "192.0.0.1";




Boucadair, et al.        Expires April 12, 2018                 [Page 9]


Internet-Draft                DS-Lite YANG                  October 2017


        description
          "IPv4 address of the DS-Lite AFTR.
          192.0.0.1 is reserved for the AFTR element.
          This address can be used to report ICMP
          problems and will appear in traceroute
          outputs.";

        reference
          "RFC 6333.";
    }

    leaf tunnel-mtu {
        type uint16;

        description
            "Configures a tunnel MTU.
            [RFC6908] specifies that since
            fragmentation and reassembly is not
            optimal, the operator should do
            everything possible to eliminate
            the need for it.  If the operator uses
            simple IPv4-in-IPv6 softwire, it is
            recommended that the MTU size of the IPv6
            network between the B4 and the AFTR
            accounts for the additional overhead
            (40 bytes).";

        reference
          "RFC 6908.";
    }

    leaf max-softwire-per-subscriber {
        type uint8;
        default 1;

        description
         "Configures the maximum softwires per subscriber
         feature.

         A subscriber is uniquely identified by means
         of subscriber-mask.

         This policy aims to prevent a misbehaving
         subscriber from mounting several DS-Lite
         softwires that would consume additional AFTR
         resources (e.g., get more external ports if
         the quota were enforced on a per-softwire basis,
         consume extra processing due to a large number



Boucadair, et al.        Expires April 12, 2018                [Page 10]


Internet-Draft                DS-Lite YANG                  October 2017


         of active softwires).";

        reference
          "Section 4 of RFC 7785.";
    }

    leaf v6-v4-dscp-preservation {
        type boolean;

        description
         "Copies the DSCP value from the IPv6 header
         and vice versa.

         According to Section 2.10 of [RFC6908],
         operators should use this model
         by provisioning the network such that
         the AFTR copies the DSCP value in the IPv4
         header to the Traffic Class field in
         the IPv6 header, after the encapsulation
         for the downstream traffic.";

        reference
          "Section 2.10 of RFC 6908.";
    }
}

// Augment NAT module with AFTR parameters

augment "/nat:nat-module/nat:nat-instances/"+
           "nat:nat-instance/nat:nat-policy" {

   when "../nat:nat-capabilities/nat:nat-flavor = 'nat:nat44'";

   description
        "Augments the NAT44 module with AFTR parameters.";

    leaf state-migrate {
        type boolean;
        default true;

        description
          "State migration is enabled by default.

           In the event a new IPv6 address is assigned to the B4 element,
           the AFTR should migrate existing state to be bound to the new
           IPv6 address.  This operation ensures that traffic destined to
           the previous B4's IPv6 address will be redirected to the newer
           B4's IPv6 address.  The destination IPv6 address for tunneling



Boucadair, et al.        Expires April 12, 2018                [Page 11]


Internet-Draft                DS-Lite YANG                  October 2017


           return traffic from the AFTR should be the last seen as the B4's
           IPv6 source address from the CPE.

           The AFTR uses the subscriber-mask to determine whether two
           IPv6 addresses belong to the same CPE (e.g., if the
           subscriber-mask is set to 56, the AFTR concludes that
           2001:db8:100:100::1 and 2001:db8:100:100::2 belong to the same
           CPE assigned with 2001:db8:100:100::/56).";

        reference
          "RFC 7785.";
    }

    container mss-clamping {
        description
          "MSS rewriting configuration to avoid IPv6
          fragmentation.";

        leaf mss-clamping-enable {
           type boolean;

           description
             "Enable/disable MSS rewriting feature.";
        }

        leaf mss-value {
           type uint16;
           units "octets";

           description
             "Sets the MSS value to be used for
              MSS rewriting.";
        }
     }
 }

// Augment NAT mapping entry:  Extended NAT44 mapping Entry

augment "/nat:nat-module/nat:nat-instances/nat:nat-instance/"+
            "nat:mapping-table/nat:mapping-entry"{

   when "../../nat:nat-capabilities/nat:nat-flavor = 'nat:nat44'";

   description
     "Augments the NAT44 mapping table with DS-Lite specifics.";


    leaf b4-ipv6-address {



Boucadair, et al.        Expires April 12, 2018                [Page 12]


Internet-Draft                DS-Lite YANG                  October 2017


        type inet:ipv6-address;

        description
            "Corresponds to the IPv6 address
            used by the B4 element.";

        reference
          "RFC 6333.";
     }

   leaf v6-dscp {
        type uint8;

        description
          "DSCP value used at the softwire level
          (i.e., IPv6 header).";
   }

   leaf internal-v4-dscp {
        type uint8;

        description
          "DSCP value of the encapsulated IPv4 packet.";
   }

   leaf external-v4-dscp {
        type uint8;

        description
          "DSCP value of the translated IPv4 packet
           as marked by the AFTR.";
   }
 }
}
<CODE ENDS>

4.  DS-Lite B4 YANG Module

   <CODE BEGINS> file "ietf-dslite-b4@2017-10-09.yang"

   module ietf-dslite-b4 {
       yang-version 1.1;
       namespace "urn:ietf:params:xml:ns:yang:ietf-dslite-b4";
       prefix dslite-b4;

       import ietf-inet-types { prefix inet; }
       import ietf-interfaces { prefix if; }
       import iana-if-type { prefix ianaift; }



Boucadair, et al.        Expires April 12, 2018                [Page 13]


Internet-Draft                DS-Lite YANG                  October 2017


       organization "Softwire Working Group";
       contact
        "Mohamed Boucadair <mohamed.boucadair@orange.com>
         Christian Jacquenet <christian.jacquenet@orange.com>
         Senthil Sivakumar <ssenthil@cisco.com>";

      description
         "This module is a YANG module for DS-Lite B4 implementations.

         Copyright (c) 2017 IETF Trust and the persons identified as
         authors of the code.  All rights reserved.

         Redistribution and use in source and binary forms, with or
         without modification, is permitted pursuant to, and subject
         to the license terms contained in, the Simplified BSD License
         set forth in Section 4.c of the IETF Trust's Legal Provisions
         Relating to IETF Documents
         (http://trustee.ietf.org/license-info).

         This version of this YANG module is part of RFC XXXX; see
         the RFC itself for full legal notices.";

       revision 2017-10-09 {
         description "Early yangdoctors review.";
         reference "-ietf-07";
       }

       revision 2017-08-10 {
         description "Augment the interfaces YANG module.";
          reference "-ietf-05";
       }

       revision 2017-07-27 {
         description "Separate B4 from AFTR.";
         reference "-ietf-04";
       }

   // Augment Interface module with DS-Lite Softwire

   augment "/if:interfaces/if:interface" {
      when "if:type = 'ianaift:tunnel'";

      description
        "Augments Interface module with B4 parameters.
        IANA interface types are maintained at this registry:
        https://www.iana.org/assignments/ianaiftype-mib/ianaiftype-mib.

          tunnel (131),       -- Encapsulation interface";



Boucadair, et al.        Expires April 12, 2018                [Page 14]


Internet-Draft                DS-Lite YANG                  October 2017


       leaf b4-ipv6-address {
           type inet:ipv6-address;

           description
             "The IPv6 address used by the B4 element.";

           reference
                "RFC 6333.";
       }

       leaf aftr-ipv6-addr {
           type inet:ipv6-address;

           description
              "The AFTR's IPv6 address.";

           reference
             "RFC 6333.";
       }

       leaf b4-ipv4-address {
           type inet:ipv4-address;
           default "192.0.0.2";

           description
             "IPv4 address of the DS-Lite B4.
             192.0.0.0/29 is reserved for the B4 element.
             This address can be used to report ICMP
             problems and will appear in traceroute
             outputs.";

           reference
              "RFC 6333.";
       }

       leaf tunnel-mtu {
           type uint16;

           description
               "Configures a tunnel MTU.
               [RFC6908] specifies that since
               fragmentation and reassembly is not
               optimal, the operator should do
               everything possible to eliminate
               the need for it.  If the operator uses
               simple IPv4-in-IPv6 softwire, it is
               recommended that the MTU size of the IPv6
               network between the B4 and the AFTR



Boucadair, et al.        Expires April 12, 2018                [Page 15]


Internet-Draft                DS-Lite YANG                  October 2017


               accounts for the additional overhead
               (40 bytes).";

            reference
                "RFC 6908.";
       }

       leaf v6-v4-dscp-preservation {
           type boolean;

           description
            "Copies the DSCP value from the IPv6 header
            and vice versa.
            Operators should use this model
            by provisioning the network such that
            the AFTR copies the DSCP value in the IPv4
            header to the Traffic Class field in
            the IPv6 header, after the encapsulation
            for the downstream traffic.";

           reference
              "Section 2.10 of RFC 6908.";
       }
     }
   }
   <CODE ENDS>

5.  Security Considerations

   The YANG module defined in this memo is designed to be accessed via
   the NETCONF protocol [RFC6241].  The lowest NETCONF layer is the
   secure transport layer and the support of SSH is mandatory to
   implement secure transport [RFC6242].  The NETCONF access control
   model [RFC6536] provides means to restrict access for particular
   NETCONF users to a pre-configured subset of all available NETCONF
   protocol operations and contents.

   All data nodes defined in the YANG module which can be created,
   modified and deleted (i.e., config true, which is the default).
   These data nodes are considered sensitive.  Write operations (e.g.,
   edit-config) applied to these data nodes without proper protection
   can negatively affect network operations.

6.  IANA Considerations

   This document requests IANA to register the following URIs in the
   "IETF XML Registry" [RFC3688]:




Boucadair, et al.        Expires April 12, 2018                [Page 16]


Internet-Draft                DS-Lite YANG                  October 2017


            URI: urn:ietf:params:xml:ns:yang:ietf-dslite-aftr
            Registrant Contact: The IESG.
            XML: N/A; the requested URI is an XML namespace.

            URI: urn:ietf:params:xml:ns:yang:ietf-dslite-b4
            Registrant Contact: The IESG.
            XML: N/A; the requested URI is an XML namespace.

   This document requests IANA to register the following YANG modules in
   the "YANG Module Names" registry [RFC7950].

            name: ietf-dslite-aftr
            namespace: urn:ietf:params:xml:ns:yang:ietf-dslite-aftr
            prefix: dslite-aftr
            reference: RFC XXXX

            name: ietf-dslite-b4
            namespace: urn:ietf:params:xml:ns:yang:ietf-dslite-b4
            prefix: dslite-b4
            reference: RFC XXXX


7.  Acknowledgements

   Thanks to Q.  Wu for identifying a compiling error.  Mahesh
   Jethanandani provided an eraly ynagdoctors review; many thanks to
   him.

   Many thanks to Ian Farrer for the review and comments

8.  References

8.1.  Normative references

   [I-D.ietf-opsawg-nat-yang]
              Boucadair, M., Sivakumar, S., Jacquenet, C., Vinapamula,
              S., and Q. Wu, "A YANG Data Model for Network Address
              Translation (NAT) and Network Prefix Translation (NPT)",
              draft-ietf-opsawg-nat-yang-05 (work in progress), October
              2017.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.







Boucadair, et al.        Expires April 12, 2018                [Page 17]


Internet-Draft                DS-Lite YANG                  October 2017


   [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,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/rfc6242>.

   [RFC6333]  Durand, A., Droms, R., Woodyatt, J., and Y. Lee, "Dual-
              Stack Lite Broadband Deployments Following IPv4
              Exhaustion", RFC 6333, DOI 10.17487/RFC6333, August 2011,
              <https://www.rfc-editor.org/info/rfc6333>.

   [RFC6536]  Bierman, A. and M. Bjorklund, "Network Configuration
              Protocol (NETCONF) Access Control Model", RFC 6536,
              DOI 10.17487/RFC6536, March 2012,
              <https://www.rfc-editor.org/info/rfc6536>.

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [RFC7223]  Bjorklund, M., "A YANG Data Model for Interface
              Management", RFC 7223, DOI 10.17487/RFC7223, May 2014,
              <https://www.rfc-editor.org/info/rfc7223>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

8.2.  Informative references

   [I-D.boucadair-pcp-yang]
              Boucadair, M., Jacquenet, C., Sivakumar, S., and S.
              Vinapamula, "YANG Data Models for the Port Control
              Protocol (PCP)", draft-boucadair-pcp-yang-04 (work in
              progress), May 2017.

   [I-D.ietf-netmod-yang-tree-diagrams]
              Bjorklund, M. and L. Berger, "YANG Tree Diagrams", draft-
              ietf-netmod-yang-tree-diagrams-01 (work in progress), June
              2017.

   [RFC6087]  Bierman, A., "Guidelines for Authors and Reviewers of YANG
              Data Model Documents", RFC 6087, DOI 10.17487/RFC6087,
              January 2011, <https://www.rfc-editor.org/info/rfc6087>.




Boucadair, et al.        Expires April 12, 2018                [Page 18]


Internet-Draft                DS-Lite YANG                  October 2017


   [RFC6908]  Lee, Y., Maglione, R., Williams, C., Jacquenet, C., and M.
              Boucadair, "Deployment Considerations for Dual-Stack
              Lite", RFC 6908, DOI 10.17487/RFC6908, March 2013,
              <https://www.rfc-editor.org/info/rfc6908>.

   [RFC7785]  Vinapamula, S. and M. Boucadair, "Recommendations for
              Prefix Binding in the Context of Softwire Dual-Stack
              Lite", RFC 7785, DOI 10.17487/RFC7785, February 2016,
              <https://www.rfc-editor.org/info/rfc7785>.










































Boucadair, et al.        Expires April 12, 2018                [Page 19]


Internet-Draft                DS-Lite YANG                  October 2017


Appendix A.  Examples

   The following example shows an AFTR that is reachable at 2001:db8::2.
   Also, this XML snippet indicates that the AFTR is provided with an
   IPv4 address (192.0.0.1) to be used for troubleshooting purposes such
   as reporting problems to B4s.  Moreover, the AFTR is instructed to
   limit the number of softwires per subscriber to '1'.

   <interface>
      <name>myAFTR</name>
      <type>ianaift:tunnel</type>
      <enabled>true</enabled>
      <aftr-ipv6-address>2001:db8::2</aftr-ipv6-address>
      <aftr-ipv4-address>192.0.0.1</aftr-ipv4-address>
      <max-softwire-per-subscriber>1</max-softwire-per-subscriber>
   </interface>

   The following shows an XML excerpt depicting a dynamic UDP mapping
   entry maintained by a DS-Lite AFTR.  In reference to this example,
   the UDP packet received with a source IPv6 address (2001:db8::1), a
   source IPv4 address (192.0.2.1) and source port number (1568) is
   translated into a UDP packet having a source IPv4 address
   (198.51.100.1) and source port (15000).  The lifetime of this mapping
   is 300 seconds.



























Boucadair, et al.        Expires April 12, 2018                [Page 20]


Internet-Draft                DS-Lite YANG                  October 2017


   <mapping-entry>
     <index>15</index>
     <type>
        dynamic-explicit
     </type>
     <transport-protocol>
        17
     </transport-protocol>
     <b4-ipv6-address>
        2001:db8::1
     </b4-ipv6-address>
     <internal-src-address>
        192.0.2.1
     </internal-dst-address>
     <internal-src-port>
        <single-port-number>
           1568
        </single-port-number>
     </internal-dst-port>
     <external-dst-address>
        198.51.100.1
     </external-dst-address>
     <external-dst-port>
        <single-port-number>
           15000
        </single-port-number>
     </external-dst-port>
     <lifetime>
        300
     </lifetime>
   </mapping-entry>

Authors' Addresses

   Mohamed Boucadair
   Orange
   Rennes  35000
   France

   EMail: mohamed.boucadair@orange.com


   Christian Jacquenet
   Orange
   Rennes  35000
   France

   EMail: christian.jacquenet@orange.com



Boucadair, et al.        Expires April 12, 2018                [Page 21]


Internet-Draft                DS-Lite YANG                  October 2017


   Senthil Sivakumar
   Cisco Systems
   7100-8 Kit Creek Road
   Research Triangle Park, North Carolina  27709
   USA

   Phone: +1 919 392 5158
   EMail: ssenthil@cisco.com











































Boucadair, et al.        Expires April 12, 2018                [Page 22]


Html markup produced by rfcmarkup 1.124, available from https://tools.ietf.org/tools/rfcmarkup/