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Versions: (draft-mahesh-babel-yang-model)  00 01         Standards Track
          02 03 04 05 06 07 08 09 10                                    
Babel Working Group                                      M. Jethanandani
Internet-Draft                                            Kloud Services
Intended status: Standards Track                                B. Stark
Expires: 13 November 2021                                           AT&T
                                                             12 May 2021


                       YANG Data Model for Babel
                     draft-ietf-babel-yang-model-10

Abstract

   This document defines a data model for the Babel routing protocol.
   The data model is defined using the YANG data modeling language.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119][RFC8174] when, and only when, they appear in all
   capitals, as shown here.

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 13 November 2021.

Copyright Notice

   Copyright (c) 2021 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.



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   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
     1.1.  Note to RFC Editor  . . . . . . . . . . . . . . . . . . .   2
     1.2.  Tree Diagram Annotations  . . . . . . . . . . . . . . . .   3
   2.  Babel Module  . . . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Information Model . . . . . . . . . . . . . . . . . . . .   3
     2.2.  Tree Diagram  . . . . . . . . . . . . . . . . . . . . . .   3
     2.3.  YANG Module . . . . . . . . . . . . . . . . . . . . . . .   5
   3.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  30
     3.1.  URI Registrations . . . . . . . . . . . . . . . . . . . .  30
     3.2.  YANG Module Name Registration . . . . . . . . . . . . . .  30
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .  30
   5.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  31
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  31
     6.1.  Normative References  . . . . . . . . . . . . . . . . . .  31
     6.2.  Informative References  . . . . . . . . . . . . . . . . .  32
   Appendix A.  An Appendix  . . . . . . . . . . . . . . . . . . . .  33
     A.1.  Statistics Gathering Enabled  . . . . . . . . . . . . . .  34
     A.2.  Automatic Detection of Properties . . . . . . . . . . . .  35
     A.3.  Override Default Properties . . . . . . . . . . . . . . .  37
     A.4.  Configuring other Properties  . . . . . . . . . . . . . .  38
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  39

1.  Introduction

   This document defines a data model for The Babel Routing Protocol
   [RFC8966].  The data model is defined using YANG 1.1 [RFC7950] data
   modeling language and is Network Management Datastore Architecture
   (NDMA) [RFC8342] compatible.  It is based on the Babel Information
   Model [I-D.ietf-babel-information-model].  The data model only
   includes data nodes that are useful for managing Babel over IPv6.

1.1.  Note to RFC Editor

   Artwork in this document contains shorthand references to drafts in
   progress.  Please apply the following replacements and remove this
   note before publication.

   *  "XXXX" --> the assigned RFC value for this draft both in this
      draft and in the YANG models under the revision statement.




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   *  "ZZZZ" --> the assigned RFC value for Babel Information Model
      [I-D.ietf-babel-information-model]

   *  Revision date in model, in the format 2021-05-12 needs to get
      updated with the date the draft gets approved.  The date also
      needs to get reflected on the line with <CODE BEGINS>.

1.2.  Tree Diagram Annotations

   For a reference to the annotations used in tree diagrams included in
   this draft, please see YANG Tree Diagrams [RFC8340].

2.  Babel Module

   This document defines a YANG 1.1 [RFC7950] data model for the
   configuration and management of Babel.  The YANG module is based on
   the Babel Information Model [I-D.ietf-babel-information-model].

2.1.  Information Model

   There are a few things that should be noted between the Babel
   Information Model and this data module.  The information model
   mandates the definition of some of the attributes, e.g.  'babel-
   implementation-version' or the 'babel-self-router-id'.  These
   attributes are marked as read-only objects in the information module
   as well as in this data module.  However, there is no way in the data
   module to mandate that a read-only attribute be present.  It is up to
   the implementation of this data module to make sure that the
   attributes that are marked read-only and are mandatory are indeed
   present.

2.2.  Tree Diagram

   The following diagram illustrates a top level hierarchy of the model.
   In addition to information like the version number implemented by
   this device, the model contains subtrees on 'constants',
   'interfaces', 'routes' and 'security'.














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   module: ietf-babel
     augment /rt:routing/rt:control-plane-protocols
               /rt:control-plane-protocol:
       +--rw babel!
          +--ro version?        string
          +--rw enable          boolean
          +--ro router-id?      binary
          +--ro seqno?          uint16
          +--rw stats-enable?   boolean
          +--rw constants
          |     ...
          +--rw interfaces* [reference]
          |     ...
          +--rw mac-key-set* [name]
          |     ...
          +--rw dtls* [name]
          |     ...
          +--ro routes* [prefix]
                ...

   The 'interfaces' subtree describes attributes such as 'interface'
   object that is being referenced, the type of link, e.g. wired,
   wireless or tunnel, as enumerated by 'metric-algorithm' and 'split-
   horizon' and whether the interface is enabled or not.

   The 'constants' subtree describes the UDP port used for sending and
   receiving Babel messages, and the multicast group used to send and
   receive announcements on IPv6.

   The 'routes' subtree describes objects such as the prefix for which
   the route is advertised, a reference to the neighboring route, and
   'next-hop' address.

   Finally, for security two subtree are defined to contain MAC keys and
   DTLS certificates.  The 'mac-key-set' subtree contains keys used with
   the MAC security mechanism.  The boolean flag 'default-apply'
   indicates whether the set of MAC keys is automatically applied to new
   interfaces.  The dtls subtree contains certificates used with DTLS
   security mechanism.  Similar to the MAC mechanism, the boolean flag
   'default-apply' indicates whether the set of DTLS certificates is
   automatically applied to new interfaces.










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2.3.  YANG Module

   This YANG module augments the YANG Routing Management [RFC8349]
   module to provide a common framework for all routing subsystems.  By
   augmenting the module it provides a common building block for routes,
   and Routing Information Bases (RIBs).  It also has a reference to an
   interface defined by A YANG Data Model for Interface Management
   [RFC8343].

   A router running Babel routing protocol can determine the parameters
   it needs to use for an interface based on the interface name.  For
   example, it can detect that eth0 is a wired interface, and that wlan0
   is a wireless interface.  This is not true for a tunnel interface,
   where the link parameters need to be configured explicitly.

   For a wired interface, it will assume 'two-out-of-three' for 'metric-
   algorithm', and 'split-horizon' set to true.  On the other hand, for
   a wireless interface it will assume 'etx' for 'metric-algorithm', and
   'split-horizon' set to false.  However, if the wired link is
   connected to a wireless radio, the values can be overriden by setting
   'metric-algorithm' to 'etx', and 'split-horizon' to false.
   Similarly, an interface that is a metered 3G link, and used for
   fallback connectivity needs much higher default time constants, e.g.
   'mcast-hello-interval', and 'update-interval', in order to avoid
   carrying control traffic as much as possible.

   In addition to the modules used above, this module imports
   definitions from Common YANG Data Types [RFC6991], and references
   HMAC: Keyed-Hashing for Message Authentication [RFC2104], Using
   HMAC-SHA-256, HMAC-SHA-384, and HMAC-SHA-512 [RFC4868], Datagram
   Transport Layer Security Version 1.2 [RFC6347], The Blake2
   Cryptographic Hash and Message Authentication Code (MAC) [RFC7693],
   Babel Information Model [I-D.ietf-babel-information-model], The Babel
   Routing Protocol [RFC8966], and MAC Authentication for Babel
   [RFC8967].

   <CODE BEGINS> file "ietf-babel@2021-05-12.yang"
   module ietf-babel {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-babel";
     prefix babel;

     import ietf-yang-types {
       prefix yang;
       reference
         "RFC 6991: Common YANG Data Types.";
     }
     import ietf-inet-types {



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       prefix inet;
       reference
         "RFC 6991: Common YANG Data Types.";
     }
     import ietf-interfaces {
       prefix if;
       reference
         "RFC 8343: A YANG Data Model for Interface Management";
     }
     import ietf-routing {
       prefix rt;
       reference
         "RFC 8349: YANG Routing Management";
     }

     organization
       "IETF Babel routing protocol Working Group";

     contact
       "WG Web: http://tools.ietf.org/wg/babel/
        WG List: babel@ietf.org

        Editor: Mahesh Jethanandani
                mjethanandani@gmail.com
        Editor: Barbara Stark
                bs7652@att.com";

     description
       "This YANG module defines a model for the Babel routing
        protocol.

        The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL
        NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED',
        'MAY', and 'OPTIONAL' in this document are to be interpreted as
        described in BCP 14 (RFC 2119) (RFC 8174) when, and only when,
        they appear in all capitals, as shown here.

        Copyright (c) 2021 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
        (https://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC XXXX



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        (https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself
        for full legal notices.";

     revision 2021-05-12 {
       description
         "Initial version.";
       reference
         "RFC XXXX: Babel YANG Data Model.";
     }

     /*
      * Features
      */

     feature two-out-of-three-supported {
       description
         "This implementation supports two-out-of-three metric
          comp algorithm.";
     }

     feature etx-supported {
       description
         "This implementation supports Expected Transmission Count
          (ETX) metric comp algorithm.";
     }

     feature mac-supported {
       description
         "This implementation supports MAC based security.";
       reference
         "RFC 8967: MAC authentication for Babel Routing
          Protocol.";
     }

     feature dtls-supported {
       description
         "This implementation supports DTLS based security.";
       reference
         "RFC 8968: Babel Routing Protocol over Datagram
          Transport Layer Security.";
     }

     feature hmac-sha256-supported {
       description
         "This implementation supports hmac-sha256 MAC algorithm.";
       reference
         "RFC 8967: MAC authentication for Babel Routing
          Protocol.";



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     }

     feature blake2s-supported {
       description
         "This implementation supports blake2s MAC algorithms.
          Specifically, BLAKE2-128 is supported.";
       reference
         "RFC 8967: MAC authentication for Babel Routing
          Protocol.";
     }

     feature x-509-supported {
       description
         "This implementation supports x-509 certificate type.";
       reference
         "RFC 8968: Babel Routing Protocol over Datagram
          Transport Layer Security.";
     }

     feature raw-public-key-supported {
       description
         "This implementation supports raw-public-key certificate
          type.";
       reference
         "RFC 8968: Babel Routing Protocol over Datagram
          Transport Layer Security.";
     }

     /*
      * Identities
      */

     identity metric-comp-algorithms {
       description
         "Base identity from which all Babel metric comp algorithms
          MUST be derived.";
     }

     identity two-out-of-three {
       base metric-comp-algorithms;
       if-feature "two-out-of-three-supported";
       description
         "2-out-of-3 algorithm.";
       reference
         "RFC 8966: The Babel Routing Protocol, Section A.2.1.";
     }

     identity etx {



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       base metric-comp-algorithms;
       if-feature "etx-supported";
       description
         "Expected Transmission Count.";
       reference
         "RFC 8966: The Babel Routing Protocol, Section A.2.2.";
     }

     /*
      * Babel MAC algorithms identities.
      */

     identity mac-algorithms {
       description
         "Base identity for all Babel MAC algorithms.";
     }

     identity hmac-sha256 {
       base mac-algorithms;
       if-feature "mac-supported";
       if-feature "hmac-sha256-supported";
       description
         "HMAC-SHA256 algorithm supported.";
       reference
         "RFC 4868: Using HMAC-SHA-256, HMAC-SHA-384, and HMAC-SHA-512
          with IPsec.";
     }

     identity blake2s {
       base mac-algorithms;
       if-feature "mac-supported";
       if-feature "blake2s-supported";
       description
         "BLAKE2s algorithms supported. Specifically, BLAKE2-128 is
          supported.";
       reference
         "RFC 7693: The BLAKE2 Cryptographic Hash and Message
          Authentication Code (MAC).";
     }

     /*
      * Babel Cert Types
      */

     identity dtls-cert-types {
       description
         "Base identity for Babel DTLS certificate types.";
     }



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     identity x-509 {
       base dtls-cert-types;
       if-feature "dtls-supported";
       if-feature "x-509-supported";
       description
         "X.509 certificate type.";
     }

     identity raw-public-key {
       base dtls-cert-types;
       if-feature "dtls-supported";
       if-feature "raw-public-key-supported";
       description
         "Raw Public Key type.";
     }

     /*
      * Babel routing protocol identity.
      */

     identity babel {
       base rt:routing-protocol;
       description
         "Babel routing protocol";
     }

     /*
      * Groupings
      */

     grouping routes {
       list routes {
         key "prefix";
         config false;

         leaf prefix {
           type inet:ip-prefix;
           description
             "Prefix (expressed in ip-address/prefix-length format) for
              which this route is advertised.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.6.";
         }

         leaf router-id {
           type binary;
           description
             "router-id of the source router for which this route is



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              advertised.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.6.";
         }

         leaf neighbor {
           type leafref {
             path "/rt:routing/rt:control-plane-protocols/"
                + "rt:control-plane-protocol/babel/interfaces/"
                + "neighbor-objects/neighbor-address";
           }
           description
             "Reference to the neighbor-objects entry for the neighbor
              that advertised this route.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.6.";
         }

         leaf received-metric {
           type uint16;
           description
             "The metric with which this route was advertised by the
              neighbor, or maximum value (infinity) to indicate the
              route was recently retracted and is temporarily
              unreachable. This metric will be 0 (zero) if the route
              was not received from a neighbor but was generated
              through other means. At least one of
              calculated-metric or received-metric MUST be non-NULL.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.6,
              RFC 8966: The Babel Routing Protocol, Section 2.1.";
         }

         leaf calculated-metric {
           type uint16;
           description
             "A calculated metric for this route. How the metric is
              calculated is implementation-specific. Maximum value
              (infinity) indicates the route was recently retracted
              and is temporarily unreachable. At least one of
              calculated-metric or received-metric MUST be non-NULL.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.6,
              RFC 8966: The Babel Routing Protocol, Section 2.1.";
         }

         leaf seqno {
           type uint16;



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           description
             "The sequence number with which this route was
              advertised.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.6.";
         }

         leaf next-hop {
           type inet:ip-address;
           description
             "The next-hop address of this route. This will be empty if
              this route has no next-hop address.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.6.";
         }

         leaf feasible {
           type boolean;
           description
             "A boolean flag indicating whether this route is
              feasible.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.6,
              RFC 8966, The Babel Routing Protocol, Section 3.5.1.";
         }

         leaf selected {
           type boolean;
           description
             "A boolean flag indicating whether this route is selected,
              i.e., whether it is currently being used for forwarding
              and is being advertised.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.6.";
         }
         description
           "A set of babel-route-obj objects. Includes received and
            routes routes.";
         reference
           "RFC ZZZZ: Babel Information Model, Section 3.1.";
       }
       description
         "Common grouping for routing used in RIB.";
     }

     /*
      * Data model
      */



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     augment "/rt:routing/rt:control-plane-protocols/"
           + "rt:control-plane-protocol" {
       when "derived-from-or-self(rt:type, 'babel')" {
         description
           "Augmentation is valid only when the instance of routing type
            is of type 'babel'.";
       }
       description
         "Augment the routing module to support a common structure
          between routing protocols.";
       reference
         "YANG Routing Management, RFC 8349, Lhotka & Lindem, March
          2018.";

       container babel {
         presence "A Babel container.";
         description
           "Babel Information Objects.";
         reference
           "RFC ZZZZ: Babel Information Model, Section 3.";

         leaf version {
           type string;
           config false;
           description
             "The name and version of this implementation of the Babel
              protocol.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.1.";
         }

         leaf enable {
           type boolean;
           mandatory true;
           description
             "When written, it configures whether the protocol should be
              enabled. A read from the <running> or <intended> datastore
              therefore indicates the configured administrative value of
              whether the protocol is enabled or not.

              A read from the <operational> datastore indicates whether
              the protocol is actually running or not, i.e. it indicates
              the operational state of the protocol.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.1.";
         }

         leaf router-id {



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           type binary;
           must '../enable = "true"';
           config false;
           description
             "Every Babel speaker is assigned a router-id, which is an
              arbitrary string of 8 octets that is assumed to be unique
              across the routing domain.

              The router-id is valid only if the protocol is enabled,
              at which time a non-zero value is assigned.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.1,
              RFC 8966: The Babel Routing Protocol,
                                           Section 3.";
         }

         leaf seqno {
           type uint16;
           config false;
           description
             "Sequence number included in route updates for routes
              originated by this node.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.1.";
         }

         leaf stats-enable {
           type boolean;
           description
             "Indicates whether statistics collection is enabled (true)
              or disabled (false) on all interfaces. When enabled,
              existing statistics values are not cleared and will be
              incremented as new packets are counted.";
         }

         container constants {
           description
             "Babel Constants object.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.1.";

           leaf udp-port {
             type inet:port-number;
             default "6696";
             description
               "UDP port for sending and receiving Babel messages. The
                default port is 6696.";
             reference



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               "RFC ZZZZ: Babel Information Model, Section 3.2.";
           }

           leaf mcast-group {
             type inet:ip-address;
             default "ff02::1:6";
             description
               "Multicast group for sending and receiving multicast
                announcements on IPv6.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.2.";
           }
         }

         list interfaces {
           key "reference";

           description
             "A set of Babel Interface objects.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.3.";

           leaf reference {
             type if:interface-ref;
             description
               "References the name of the interface over which Babel
                packets are sent and received.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf enable {
             type boolean;
             default "true";
             description
               "If true, babel sends and receives messages on this
                interface. If false, babel messages received on this
                interface are ignored and none are sent.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf metric-algorithm {
             type identityref {
               base metric-comp-algorithms;
             }
             mandatory true;
             description



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               "Indicates the metric computation algorithm used on this
                interface. The value MUST be one of those identities
                based on 'metric-comp-algorithms'.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf split-horizon {
             type boolean;
             description
               "Indicates whether or not the split horizon optimization
                is used when calculating metrics on this interface.
                A value of true indicates split horizon optimization
                is used.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf mcast-hello-seqno {
             type uint16;
             config false;
             description
               "The current sequence number in use for multicast hellos
                sent on this interface.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf mcast-hello-interval {
             type uint16;
             units "centiseconds";
             description
               "The current multicast hello interval in use for hellos
                sent on this interface.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf update-interval {
             type uint16;
             units "centiseconds";
             description
               "The current update interval in use for this interface.
                Units are centiseconds.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }




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           leaf mac-enable {
             type boolean;
             description
               "Indicates whether the MAC security mechanism is enabled
                (true) or disabled (false).";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf-list mac-key-sets {
             type leafref {
               path "../../mac-key-set/name";
             }
             description
               "List of references to the mac entries that apply
                to this interface. When an interface instance is
                created, all mac instances with default-apply 'true'
                will be included in this list.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf mac-verify {
             type boolean;
             description
               "A Boolean flag indicating whether MACs in
                incoming Babel packets are required to be present and
                are verified.  If this parameter is 'true', incoming
                packets are required to have a valid MAC.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf dtls-enable {
             type boolean;
             description
               "Indicates whether the DTLS security mechanism is enabled
                (true) or disabled (false).";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf-list dtls-certs {
             type leafref {
               path "../../dtls/name";
             }
             description
               "List of references to the dtls entries that apply to



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                this interface.  When an interface instance
                is created, all dtls instances with default-apply
                'true' will be included in this list.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           leaf dtls-cached-info {
             type boolean;
             description
               "Indicates whether the cached_info extension is included
                in ClientHello and ServerHello packets. The extension
                is included if the value is 'true'.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.
                RFC 8968: Babel Routing Protocol over
                Datagram Transport Layer Security, Appendix A.";
           }

           leaf-list dtls-cert-prefer {
             type leafref {
               path "../../dtls/certs/type";
             }
             ordered-by user;
             description
               "List of supported certificate types, in order of
                preference. The values MUST be among those listed in
                dtls-cert-types. This list is used to populate the
                server_certificate_type extension in a Client Hello.
                Values that are present in at least one instance in the
                certs object under dtls of a referenced dtls instance
                and that have a non-empty private-key will be used to
                populate the client_certificate_type extension in a
                Client Hello.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3
                RFC 8968: Babel Routing Protocol over
                Datagram Transport Layer Security, Appendix A.";
           }

           leaf packet-log-enable {
             type boolean;
             description
               "If true, logging of babel packets received on this
                interface is enabled; if false, babel packets are not
                logged.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";



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           }

           leaf packet-log {
             type inet:uri;
             config false;
             description
               "A reference or url link to a file that contains a
                timestamped log of packets received and sent on
                udp-port on this interface. The [libpcap] file
                format with .pcap file extension SHOULD be supported for
                packet log files. Logging is enabled / disabled by
                packet-log-enable.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";
           }

           container stats {
             config false;
             description
               "Statistics collection object for this interface.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.3.";

             leaf sent-mcast-hello {
               type yang:counter32;
               description
                 "A count of the number of multicast Hello packets sent
                  on this interface.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.4.";
             }

             leaf sent-mcast-update {
               type yang:counter32;
               description
                 "A count of the number of multicast update packets sent
                  on this interface.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.4.";
             }

             leaf sent-ucast-hello {
               type yang:counter32;
               description
                 "A count of the number of unicast Hello packets sent
                  on this interface.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.6.";



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             }

             leaf sent-ucast-update {
               type yang:counter32;
               description
                 "A count of the number of unicast update packets sent
                  on this interface.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.6.";
             }

             leaf sent-ihu {
               type yang:counter32;
               description
                 "A count of the number of IHU packets sent on this
                  interface.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.6.";
             }

             leaf received-packets {
               type yang:counter32;
               description
                 "A count of the number of Babel packets received on
                  this interface.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.4.";
             }

             action reset {
               description
                 "The information model [RFC ZZZZ] defines reset
                  action as a system-wide reset of Babel statistics.
                  In YANG the reset action is associated with the
                  container where the action is defined. In this case
                  the action is associated with the stats container
                  inside an interface. The action will therefore
                  reset statistics at an interface level.

                  Implementations that want to support a system-wide
                  reset of Babel statistics need to call this action
                  for every instance of the interface.";

               input {
                 leaf reset-at {
                   type yang:date-and-time;
                   description
                     "The time when the reset was issued.";



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                 }
               }

               output {
                 leaf reset-finished-at {
                   type yang:date-and-time;
                   description
                     "The time when the reset finished.";
                 }
               }
             }
           }

           list neighbor-objects {
             key "neighbor-address";
             config false;
             description
               "A set of Babel Neighbor Object.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.5.";

             leaf neighbor-address {
               type inet:ip-address;
               description
                 "IPv4 or v6 address the neighbor sends packets from.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.5.";
             }

             leaf hello-mcast-history {
               type string;
               description
                 "The multicast Hello history of whether or not the
                  multicast Hello packets prior to exp-mcast-
                  hello-seqno were received, with a '1' for the most
                  recent Hello placed in the most significant bit and
                  prior Hellos shifted right (with '0' bits placed
                  between prior Hellos and most recent Hello for any
                  not-received Hellos); represented as a string using
                  utf-8 encoded hex digits where a '1' bit = Hello
                  received and a '0' bit = Hello not received.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.5.";
             }

             leaf hello-ucast-history {
               type string;
               description



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                 "The unicast Hello history of whether or not the
                  unicast Hello packets prior to exp-ucast-hello-seqno
                  were received, with a '1' for the most
                  recent Hello placed in the most significant bit and
                  prior Hellos shifted right (with '0' bits placed
                  between prior Hellos and most recent Hello for any
                  not-received Hellos); represented as a string using
                  utf-8 encoded hex digits where a '1' bit = Hello
                  received and a '0' bit = Hello not received.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.5.";
             }

             leaf txcost {
               type int32;
               default "0";
               description
                 "Transmission cost value from the last IHU packet
                  received from this neighbor, or maximum value
                  (infinity) to indicate the IHU hold timer for this
                  neighbor has expired description.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.5.";
             }

             leaf exp-mcast-hello-seqno {
               type uint16;
               default "0";
               description
                 "Expected multicast Hello sequence number of next Hello
                  to be received from this neighbor; if multicast Hello
                  packets are not expected, or processing of multicast
                  packets is not enabled, this MUST be NULL.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.5.";
             }

             leaf exp-ucast-hello-seqno {
               type uint16;
               default "0";
               description
                 "Expected unicast Hello sequence number of next Hello
                  to be received from this neighbor; if unicast Hello
                  packets are not expected, or processing of unicast
                  packets is not enabled, this MUST be NULL.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.5.";
             }



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             leaf ucast-hello-seqno {
               type uint16;
               default "0";
               description
                 "The current sequence number in use for unicast Hellos
                  sent to this neighbor. If unicast Hellos are not being
                  sent, this MUST be NULL.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.5.";
             }

             leaf ucast-hello-interval {
               type uint16;
               units "centiseconds";
               description
                 "The current interval in use for unicast hellos sent to
                  this neighbor. Units are centiseconds.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.5.";
             }

             leaf rxcost {
               type uint16;
               description
                 "Reception cost calculated for this neighbor. This
                  value is usually derived from the Hello history, which
                  may be combined with other data, such as statistics
                  maintained by the link layer. The rxcost is sent to a
                  neighbor in each IHU.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.5.";
             }

             leaf cost {
               type int32;
               description
                 "Link cost is computed from the values maintained in
                  the neighbor table. The statistics kept in the
                  neighbor table about the reception of Hellos, and the
                  txcost computed from received IHU packets.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.5.";
             }
           }
         }

         list mac-key-set {
           key "name";



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           description
             "A mac key set object. If this object is implemented, it
              provides access to parameters related to the MAC security
              mechanism.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.7.";

           leaf name {
             type string;
             description
               "A string that uniquely identifies the mac object.";
           }

           leaf default-apply {
             type boolean;
             description
               "A Boolean flag indicating whether this object
                instance is applied to all new interfaces, by default.
                If 'true', this instance is applied to new babel-
                interfaces instances at the time they are created,
                by including it in the mac-key-sets list under
                interfaces. If 'false', this instance is not applied
                to new interfaces instances when they are created.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.7.";
           }

           list keys {
             key "name";
             min-elements 1;
             description
               "A set of keys objects.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.8.";

             leaf name {
               type string;
               description
                 "A unique name for this MAC key that can be used to
                  identify the key in this object instance, since the
                  key value is not allowed to be read. This value can
                  only be provided when this instance is created, and is
                  not subsequently writable.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.8.";
             }

             leaf use-send {



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               type boolean;
               mandatory true;
               description
                 "Indicates whether this key value is used to compute a
                  MAC and include that MAC in the sent Babel packet. A
                  MAC for sent packets is computed using this key if the
                  value is 'true'. If the value is 'false', this key is
                  not used to compute a MAC to include in sent Babel
                  packets.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.8.";
             }

             leaf use-verify {
               type boolean;
               mandatory true;
               description
                 "Indicates whether this key value is used to verify
                  incoming Babel packets. This key is used to verify
                  incoming packets if the value is 'true'. If the value
                  is 'false', no MAC is computed from this key for
                  comparing an incoming packet.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.8.";
             }

             leaf value {
               type binary;
               mandatory true;
               description
                 "The value of the MAC key. An implementation MUST NOT
                  allow this parameter to be read. This can be done by
                  always providing an empty string, or through
                  permissions, or other means. This value MUST be
                  provided when this instance is created, and is not
                  subsequently writable.

                  This value is of a length suitable for the associated
                  babel-mac-key-algorithm.  If the algorithm is based on
                  the HMAC construction [RFC2104], the length MUST be
                  between 0 and an upper limit that is at least the size
                  of the output length (where 'HMAC-SHA256' output
                  length is 32 octets as described in [RFC4868]). Longer
                  lengths MAY be supported but are not necessary if the
                  management system has the ability to generate a
                  suitably random value (e.g., by randomly generating a
                  value or by using a key derivation technique as
                  recommended in [RFC8967] Security Considerations). If



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                  the algorithm is 'BLAKE2s-128', the length MUST be
                  between 0 and 32 bytes inclusive as specified by
                  [RFC7693].";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.8,
                  RFC 2104: HMAC: Keyed-Hashing for Message
                            Authentication
                  RFC 4868: Using HMAC-SHA-256, HMAC-SHA-384, and
                            HMAC-SHA-512 with IPsec,
                  RFC 7693: The BLAKE2 Cryptographic Hash and Message
                            Authentication Code (MAC).
                  RFC 8967:  MAC Authentication for Babel.";
             }

             leaf algorithm {
               type identityref {
                 base mac-algorithms;
               }
               mandatory true;
               description
                 "The name of the MAC algorithm used with this key. The
                  value MUST be the same as one of the enumerations
                  listed in the mac-algorithms parameter.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.8.";
             }

             action test {
               description
                 "An operation that allows the MAC key and MAC
                  algorithm to be tested to see if they produce an
                  expected outcome. Input to this operation are a
                  binary string and a calculated MAC (also in the
                  format of a binary string) for the binary string.
                  The implementation is expected to create a MAC over
                  the binary string using the value and algorithm.
                  The output of this operation is a binary indication
                  that the calculated MAC matched the input MAC (true)
                  or the MACs did not match (false).";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.8.";

               input {
                 leaf test-string {
                   type binary;
                   mandatory true;
                   description
                     "Input to this operation is a binary string.



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                      The implementation is expected to create
                      a MAC over this string using the value and
                      the algorithm defined as part of the
                      mac-key-set.";
                   reference
                     "RFC ZZZZ: Babel Information Model, Section 3.8.";
                 }

                 leaf mac {
                   type binary;
                   mandatory true;
                   description
                     "Input to this operation includes a MAC.
                      The implementation is expected to calculate a MAC
                      over the string using the value and algorithm of
                      this key object and compare its calculated MAC to
                      this input MAC.";
                   reference
                     "RFC ZZZZ: Babel Information Model, Section 3.8.";
                 }
               }

               output {
                 leaf indication {
                   type boolean;
                   mandatory true;
                   description
                     "The output of this operation is a binary
                      indication that the calculated MAC matched the
                      input MAC (true) or the MACs did not match
                      (false).";
                   reference
                     "RFC ZZZZ: Babel Information Model, Section 3.8.";
                 }
               }
             }
           }
         }

         list dtls {
           key "name";

           description
             "A dtls object. If this object is implemented,
              it provides access to parameters related to the DTLS
              security mechanism.";
           reference
             "RFC ZZZZ: Babel Information Model, Section 3.9";



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           leaf name {
             type string;
             description
               "A string that uniquely identifies a dtls object.";
           }

           leaf default-apply {
             type boolean;
             mandatory true;
             description
               "A Boolean flag indicating whether this object
                instance is applied to all new interfaces, by default.
                If 'true', this instance is applied to new interfaces
                instances at the time they are created, by including it
                in the dtls-certs list under interfaces. If 'false',
                this instance is not applied to new interfaces
                instances when they are created.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.9.";
           }

           list certs {
             key "name";

             min-elements 1;
             description
               "A set of cert objects. This contains
                both certificates for this implementation to present
                for authentication, and to accept from others.
                Certificates with a non-empty private-key
                can be presented by this implementation for
                authentication.";
             reference
               "RFC ZZZZ: Babel Information Model, Section 3.10.";

             leaf name {
               type string;
               description
                 "A unique name for this certificate that can be
                  used to identify the certificate in this object
                  instance, since the value is too long to be useful
                  for identification. This value MUST NOT be empty
                  and can only be provided when this instance is created
                  (i.e., it is not subsequently writable).";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.10.";
             }




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             leaf value {
               type string;
               mandatory true;
               description
                 "The certificate in PEM format [RFC7468]. This
                  value can only be provided when this instance is
                  created, and is not subsequently writable.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.10.";
             }

             leaf type {
               type identityref {
                 base dtls-cert-types;
               }
               mandatory true;
               description
                 "The name of the certificate type of this object
                  instance. The value MUST be the same as one of the
                  enumerations listed in the dtls-cert-types
                  parameter. This value can only be provided when this
                  instance is created, and is not subsequently
                  writable.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.10.";
             }

             leaf private-key {
               type binary;
               mandatory true;
               description
                 "The value of the private key. If this is non-empty,
                  this certificate can be used by this implementation to
                  provide a certificate during DTLS handshaking. An
                  implementation MUST NOT allow this parameter to be
                  read. This can be done by always providing an empty
                  string, or through permissions, or other means. This
                  value can only be provided when this instance is
                  created, and is not subsequently writable.";
               reference
                 "RFC ZZZZ: Babel Information Model, Section 3.10.";
             }
           }
         }
         uses routes;
       }
     }
   }



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   <CODE ENDS>

3.  IANA Considerations

   This document registers one URIs and one YANG module.

3.1.  URI Registrations

   URI: urn:ietf:params:xml:ns:yang:ietf-babel

3.2.  YANG Module Name Registration

   This document registers one YANG module in the YANG Module Names
   registry YANG [RFC6020].

   Name:ietf-babel
   Namespace: urn:ietf:params:xml:ns:yang:ietf-babel
   prefix: babel
   reference: RFC XXXX

4.  Security Considerations

   The YANG module specified in this document defines a schema for data
   that is designed to be accessed via network management protocol such
   as NETCONF [RFC6241] or RESTCONF [RFC8040].  The lowest NETCONF layer
   is the secure transport layer and the mandatory-to-implement secure
   transport is SSH [RFC6242].  The lowest RESTCONF layer is HTTPS, and
   the mandatory-to-implement secure transport is TLS [RFC8446].

   The NETCONF Access Control Model (NACM [RFC8341]) provides the means
   to restrict access for particular NETCONF users to a pre-configured
   subset of all available NETCONF protocol operations and content.

   There are a number of data nodes defined in the YANG module which are
   writable/created/deleted (i.e., config true, which is the default).
   These data nodes may be considered sensitive or vulnerable in some
   network environments.  Write operations (e.g., <edit-config>) to
   these data nodes without proper protection can have a negative effect
   on network operations.  These are the subtrees and data nodes and
   their sensitivity/vulnerability from a config true perspective:

   'babel': This container includes an 'enable' parameter that can be
   used to enable or disable use of Babel on a router

   'babel/constants': This container includes configuration parameters
   that can prevent reachability if misconfigured.





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   'babel/interfaces': This leaf-list has configuration parameters that
   can enable/disable security mechanisms and change performance
   characteristics of the Babel protocol.

   'babel/hmac' and 'babel/dtls': These contain security credentials
   that influence whether packets are trusted.

   Some of the readable data or config false nodes in this YANG module
   may be considered sensitive or vulnerable in some network
   environments.  It is thus important to control read access (e.g., via
   get, get-config, or notification) to these data nodes.  These are the
   subtrees and data nodes and their sensitivity/vulnerability from a
   config false perpective:

   'babel': Access to the information in the various nodes can disclose
   the network topology.  Additionally, the routes used by a network
   device may be used to mount a subsequent attack on traffic traversing
   the network device.

   'babel/hmac' and 'babel/dtls': These contain security credentials,
   include private credentials of the router.

   Some of the RPC operations in this YANG module may be considered
   sensitive or vulnerable in some network environments.  It is thus
   important to control access to these operations.  These are the
   operations and their sensitivity/vulnerability from a RPC operation
   perspective:

   This model does not define any RPC operations.

5.  Acknowledgements

   Juliusz Chroboczek provided most of the example configurations for
   babel that are shown in the Appendix.

6.  References

6.1.  Normative References

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

   [RFC4868]  Kelly, S. and S. Frankel, "Using HMAC-SHA-256, HMAC-SHA-
              384, and HMAC-SHA-512 with IPsec", RFC 4868,
              DOI 10.17487/RFC4868, May 2007,
              <https://www.rfc-editor.org/info/rfc4868>.



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   [RFC6347]  Rescorla, E. and N. Modadugu, "Datagram Transport Layer
              Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347,
              January 2012, <https://www.rfc-editor.org/info/rfc6347>.

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

   [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>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8343]  Bjorklund, M., "A YANG Data Model for Interface
              Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
              <https://www.rfc-editor.org/info/rfc8343>.

   [RFC8349]  Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for
              Routing Management (NMDA Version)", RFC 8349,
              DOI 10.17487/RFC8349, March 2018,
              <https://www.rfc-editor.org/info/rfc8349>.

   [RFC8966]  Chroboczek, J. and D. Schinazi, "The Babel Routing
              Protocol", RFC 8966, DOI 10.17487/RFC8966, January 2021,
              <https://www.rfc-editor.org/info/rfc8966>.

   [RFC8967]  Dô, C., Kolodziejak, W., and J. Chroboczek, "MAC
              Authentication for the Babel Routing Protocol", RFC 8967,
              DOI 10.17487/RFC8967, January 2021,
              <https://www.rfc-editor.org/info/rfc8967>.

6.2.  Informative References

   [I-D.ietf-babel-information-model]
              Stark, B. and M. Jethanandani, "Babel Information Model",
              Work in Progress, Internet-Draft, draft-ietf-babel-
              information-model-14, 11 March 2021,
              <https://www.ietf.org/archive/id/draft-ietf-babel-
              information-model-14.txt>.

   [RFC2104]  Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed-
              Hashing for Message Authentication", RFC 2104,
              DOI 10.17487/RFC2104, February 1997,
              <https://www.rfc-editor.org/info/rfc2104>.




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

   [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>.

   [RFC7693]  Saarinen, M-J., Ed. and J-P. Aumasson, "The BLAKE2
              Cryptographic Hash and Message Authentication Code (MAC)",
              RFC 7693, DOI 10.17487/RFC7693, November 2015,
              <https://www.rfc-editor.org/info/rfc7693>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

   [RFC8340]  Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
              BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
              <https://www.rfc-editor.org/info/rfc8340>.

   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/info/rfc8341>.

   [RFC8342]  Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              and R. Wilton, "Network Management Datastore Architecture
              (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
              <https://www.rfc-editor.org/info/rfc8342>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

Appendix A.  An Appendix

   This section is devoted to examples that demonstrate how Babel can be
   configured.






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A.1.  Statistics Gathering Enabled

   In this example, interface eth0 is being configured for routing
   protocol Babel, and statistics gathering is enabled.  For security,
   HMAC-SHA256 is supported.  Every sent Babel packets is signed with
   the key value provided, and every received Babel packet is verified
   with the same key value.












































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 <?xml version="1.0" encoding="UTF-8"?>
 <config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
   <interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces"
               xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
     <interface>
       <name>eth0</name>
       <type>ianaift:ethernetCsmacd</type>
       <enabled>true</enabled>
     </interface>
   </interfaces>
   <routing
       xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
     <control-plane-protocols>
       <control-plane-protocol>
         <type
             xmlns:babel=
             "urn:ietf:params:xml:ns:yang:ietf-babel">babel:babel
         </type>
         <name>name:babel</name>
         <babel
             xmlns="urn:ietf:params:xml:ns:yang:ietf-babel">
           <enable>true</enable>
           <stats-enable>true</stats-enable>
           <interfaces>
             <reference>eth0</reference>
             <metric-algorithm>two-out-of-three</metric-algorithm>
             <split-horizon>true</split-horizon>
           </interfaces>
           <mac-key-set>
             <name>hmac-sha256</name>
             <keys>
               <name>hmac-sha256-keys</name>
               <use-send>true</use-send>
               <use-verify>true</use-verify>
               <value>base64encodedvalue==</value>
               <algorithm>hmac-sha256</algorithm>
             </keys>
           </mac-key-set>
         </babel>
       </control-plane-protocol>
     </control-plane-protocols>
   </routing>
 </config>

A.2.  Automatic Detection of Properties






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 <!-- In this example, babeld is configured on two interfaces

    interface eth0
    interface wlan0

    This says to run Babel on interfaces eth0 and wlan0.  Babeld will
    automatically detect that eth0 is wired and wlan0 is wireless, and
    will configure the right parameters automatically.
 -->

 <?xml version="1.0" encoding="UTF-8"?>
 <config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
   <interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces"
               xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
     <interface>
       <name>eth0</name>
       <type>ianaift:ethernetCsmacd</type>
       <enabled>true</enabled>
     </interface>
     <interface>
       <name>wlan0</name>
       <type>ianaift:ieee80211</type>
       <enabled>true</enabled>
     </interface>
   </interfaces>
   <routing
       xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
     <control-plane-protocols>
       <control-plane-protocol>
         <type
             xmlns:babel=
             "urn:ietf:params:xml:ns:yang:ietf-babel">babel:babel
         </type>
         <name>name:babel</name>
         <babel
             xmlns="urn:ietf:params:xml:ns:yang:ietf-babel">
           <enable>true</enable>
           <interfaces>
             <reference>eth0</reference>
             <enable>true</enable>
             <metric-algorithm>two-out-of-three</metric-algorithm>
             <split-horizon>true</split-horizon>
           </interfaces>
           <interfaces>
             <reference>wlan0</reference>
             <enable>true</enable>
             <metric-algorithm>etx</metric-algorithm>
             <split-horizon>false</split-horizon>



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           </interfaces>
         </babel>
       </control-plane-protocol>
     </control-plane-protocols>
   </routing>
 </config>

A.3.  Override Default Properties

 <!-- In this example, babeld is configured on three interfaces

  interface eth0
  interface eth1 type wireless
  interface tun0 type tunnel

  Here, interface eth1 is an Ethernet bridged to a wireless radio, so
  babeld's autodetection fails, and the interface type needs to be
  configured manually.  Tunnels are not detected automatically, so this
  needs to be specified.

  This is equivalent to the following:

  interface eth0 metric-algorithm 2-out-of-3 split-horizon true
  interface eth1 metric-algorithm etx split-horizon false
  interface tun0 metric-algorithm 2-out-of-3 split-horizon true
 -->

 <?xml version="1.0" encoding="UTF-8"?>
 <config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
   <interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces"
               xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
     <interface>
       <name>eth0</name>
       <type>ianaift:ethernetCsmacd</type>
       <enabled>true</enabled>
     </interface>
     <interface>
       <name>eth1</name>
       <type>ianaift:ethernetCsmacd</type>
       <enabled>true</enabled>
     </interface>
     <interface>
       <name>tun0</name>
       <type>ianaift:tunnel</type>
       <enabled>true</enabled>
     </interface>
   </interfaces>
   <routing



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       xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
     <control-plane-protocols>
       <control-plane-protocol>
         <type
             xmlns:babel=
             "urn:ietf:params:xml:ns:yang:ietf-babel">babel:babel
         </type>
         <name>name:babel</name>
         <babel
             xmlns="urn:ietf:params:xml:ns:yang:ietf-babel">
           <enable>true</enable>
           <interfaces>
             <reference>eth0</reference>
             <enable>true</enable>
             <metric-algorithm>two-out-of-three</metric-algorithm>
             <split-horizon>true</split-horizon>
           </interfaces>
           <interfaces>
             <reference>eth1</reference>
             <enable>true</enable>
             <metric-algorithm>etx</metric-algorithm>
             <split-horizon>false</split-horizon>
           </interfaces>
           <interfaces>
             <reference>tun0</reference>
             <enable>true</enable>
             <metric-algorithm>two-out-of-three</metric-algorithm>
             <split-horizon>true</split-horizon>
           </interfaces>
         </babel>
       </control-plane-protocol>
     </control-plane-protocols>
   </routing>
 </config>

A.4.  Configuring other Properties

<!-- In this example, two interfaces are configured for babeld

 interface eth0
 interface ppp0 hello-interval 30 update-interval 120

 Here, ppp0 is a metered 3G link used for fallback connectivity. It runs
 with much higher than default time constants in order to avoid control
 traffic as much as possible.
-->

<?xml version="1.0" encoding="UTF-8"?>



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<config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
  <interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces"
              xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">
    <interface>
      <name>eth0</name>
      <type>ianaift:ethernetCsmacd</type>
      <enabled>true</enabled>
    </interface>
    <interface>
      <name>ppp0</name>
      <type>ianaift:ppp</type>
      <enabled>true</enabled>
    </interface>
  </interfaces>
  <routing
      xmlns="urn:ietf:params:xml:ns:yang:ietf-routing">
    <control-plane-protocols>
      <control-plane-protocol>
        <type
            xmlns:babel=
            "urn:ietf:params:xml:ns:yang:ietf-babel">babel:babel
        </type>
        <name>name:babel</name>
        <babel
            xmlns="urn:ietf:params:xml:ns:yang:ietf-babel">
          <enable>true</enable>
          <interfaces>
            <reference>eth0</reference>
            <enable>true</enable>
            <metric-algorithm>two-out-of-three</metric-algorithm>
            <split-horizon>true</split-horizon>
          </interfaces>
          <interfaces>
            <reference>ppp0</reference>
            <enable>true</enable>
            <mcast-hello-interval>30</mcast-hello-interval>
            <update-interval>120</update-interval>
            <metric-algorithm>two-out-of-three</metric-algorithm>
          </interfaces>
        </babel>
      </control-plane-protocol>
    </control-plane-protocols>
  </routing>
</config>

Authors' Addresses





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   Mahesh Jethanandani
   Kloud Services
   California
   United States of America

   Email: mjethanandani@gmail.com


   Barbara Stark
   AT&T
   Atlanta, GA
   United States of America

   Email: barbara.stark@att.com





































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