Babel Information Model
draft-ietf-babel-information-model-00

Babel routing protocol                                          B. Stark
Internet-Draft                                                      AT&T
Intended status: Informational                              July 3, 2017
Expires: January 4, 2018

                        Babel Information Model
                 draft-ietf-babel-information-model-00

Abstract

   This Babel Information Model can be used to create data models under
   various data modeling regimes (e.g., YANG).  It allows a Babel
   implementation (via a management protocol such as netconf) to report
   on its current state and may allow some limited configuration of
   protocol constants.

Status of This Memo

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

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

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

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

Stark                    Expires January 4, 2018                [Page 1]
Internet-Draft           Babel Information Model               July 2017

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Requirements Language . . . . . . . . . . . . . . . . . .   3
     1.2.  Notation  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  The Information Model . . . . . . . . . . . . . . . . . . . .   3
     2.1.  Definition of babel-information . . . . . . . . . . . . .   3
     2.2.  Definition of babel-constants . . . . . . . . . . . . . .   4
     2.3.  Definition of babel-interfaces  . . . . . . . . . . . . .   4
     2.4.  Definition of babel-neighbors . . . . . . . . . . . . . .   5
     2.5.  Definition of babel-csa . . . . . . . . . . . . . . . . .   5
     2.6.  Definition of babel-sources . . . . . . . . . . . . . . .   6
     2.7.  Definition of babel-routes  . . . . . . . . . . . . . . .   6
   3.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .   7
   4.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   7
     4.1.  Normative References  . . . . . . . . . . . . . . . . . .   7
     4.2.  Informative References  . . . . . . . . . . . . . . . . .   7
   Appendix A.  Open Issues  . . . . . . . . . . . . . . . . . . . .   8
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .   8

1.  Introduction

   Babel is a loop-avoiding distance-vector routing protocol defined in
   RFC 6126 [RFC6126] and draft-ietf-babel-rfc6126bis
   [babel-rfc6126bis].  Babel Hashed Message Authentication Code (HMAC)
   Cryptographic Authentication, defined in RFC 7298 [RFC7298],
   describes a cryptographic authentication mechanism for the Babel
   routing protocol.  This document describes an information model for
   Babel (including HMAC) that can be used to created management
   protocol data models (such as a netconf [RFC6241] YANG data model).
   Other Babel extensions may be included in this document when they
   become working group drafts.

   Due to the simplicity of the Babel protocol and the fact that it is
   designed to be used in non-professionally administered environments
   (such as home networks), most of the information model is focused on
   reporting status of the Babel protocol, and very little of that is
   considered mandatory to implement (conditional on a management
   protocol with Babel support being implemented).  Some parameters may
   be configurable; however, it is up to the Babel implementation
   whether to allow any of these to be configured within its
   implementation.  Where the implementation does not allow
   configuration of these parameters, it may still choose to expose them
   as read-only.

Stark                    Expires January 4, 2018                [Page 2]
Internet-Draft           Babel Information Model               July 2017

1.1.  Requirements Language

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

1.2.  Notation

   This document uses a programming language-like notation to define the
   properties of the objects of the information model.  An optional
   property is enclosed by square brackets, [ ], and a list property is
   indicated by two numbers in angle brackets, <m..n>, where m indicates
   the minimal number of values, and n is the maximum.  The symbol * for
   n means no upper bound.

2.  The Information Model

2.1.  Definition of babel-information

        object {
             string                babel-implementation-version;
             int                   babel-self-router-id;
            [int                   babel-self-seqno;]
             string                babel-cost-comp-algorithms<1..*>;
             babel-constants-obj   babel-constants;
             babel-interfaces-obj  babel-interfaces<0..*>;
             babel-sources-obj     babel-sources<0..*>;
             babel-routes-obj      babel-routes<0..*>;
         }babel-information-obj;

      babel-version: the version of this implementation of the Babel
      protocol

      babel-self-router-id: the router-id used by this instance of the
      Babel protocol to identify itself

      babel-self-seqno: the current sequence number included in route
      updates for routes originated by this node

      babel-cost-comp-algorithm: a set of names of supported cost
      computation algorithms; possible values include "k-out-of-j",
      "ETX"

      babel-constants: a babel-constants object

      babel-interfaces: a set of babel-interface objects

      babel-sources: a set of babel-source objects

Stark                    Expires January 4, 2018                [Page 3]
Internet-Draft           Babel Information Model               July 2017

      babel-routes: a set of babel-route objects

2.2.  Definition of babel-constants

        object {
             int          babel-udp-port;
            [int          babel-multicast-group-ipv6;]
            [int          babel-multicast-group-ipv4;]
         }babel-constants-obj;

      babel-udp-port: UDP port for sending and listening for Babel
      messages; default is 6696; MAY be configurable

      babel-multicast-group-ipv6: multicast group for sending and
      listening to multicast announcements on IPv6; default is
      ff02:0:0:0:0:0:1:6; MAY be configurable

      babel-multicast-group-ipv4: multicast group for sending and
      listening to multicast announcements on IPv4; default is
      224.0.0.111; MAY be configurable

2.3.  Definition of babel-interfaces

        object {
             uri                  babel-interface-reference;
            [int                  babel-interface-seqno;]
            [int                  babel-interface-hello-interval;]
            [int                  babel-interface-update-interval;]
             boolean              babel-request-trigger-ack;
             boolean              babel-lossy-link;
            [int                  babel-external-cost;]
             babel-neighbors-obj  babel-neighbors<1..*>;
            [babel-csa-obj        babel-csa<1..*>;]
         }babel-interfaces-obj;

      babel-interface-reference: reference to an interface object as
      defined by the data model

      babel-interface-seqno: the current sequence number in use for this
      interface

      babel-interface-hello-interval: the current hello interval in use
      for this interface

      babel-interface-update-interval: the current update interval in
      use for this interface

Stark                    Expires January 4, 2018                [Page 4]
Internet-Draft           Babel Information Model               July 2017

      babel-request-trigger-ack: requests acknowledgement of triggered
      updates (if number of neighbors less than babel-ack-limit); MAY be
      configurable

      babel-lossy-link: indicates (if true) that the link of this
      interface is considered lossy; MAY be configurable

      babel-external-cost: external input to cost of link of this
      interface (need to determine how to express this);MUST be
      configurable if implemented

2.4.  Definition of babel-neighbors

        object {
             some address format  babel-neighbor-address;
             string               babel-hello-history;
             int                  babel-txcost;
             int                  babel-hello-seqno;
             int                  babel-neighbor-ihu-interval;
            [int                  babel-rxcost]
         }babel-neighbors-obj;

      babel-neighbor-address: (IPv4 or v6) address the neighbor sends
      messages from

      babel-hello-history: the Hello history (do we want a human
      readable format?)

      babel-txcost: transmission cost value from the last IHU packet
      received from this neighbor, or FFFF hexadecimal (infinity) if the
      IHU hold timer for this neighbor has expired

      babel-hello-seqno: expected Hello sequence number

      babel-neighbor-ihu-interval: current IHU interval for this
      neighbor

      babel-router-id: router-id of the neighbor

      babel-rxcost: reception cost calculated for this neighbor

2.5.  Definition of babel-csa

        object {
             string               placeholder;
       }babel-csa-obj;

      placeholder: this section to be filled in, in the future

Stark                    Expires January 4, 2018                [Page 5]
Internet-Draft           Babel Information Model               July 2017

2.6.  Definition of babel-sources

        object {
             (prefix, plen)       babel-source-prefix;
             int                  babel-source-router-id;
             int                  babel-source-seqno;
             int                  babel-source-metric;
            [int                  babel-source-garbage-collection-time;]
         }babel-sources-obj;

      babel-source-prefix: Prefix (with prefix length)

      babel-source-router-id: router-id of the router originating this
      prefix

      babel-source-seqno: last sequence number used by this source

      babel-source-metric: this source's feasibility distance

      babel-source-garbage-collection-time: garbage-collection timer for
      this source

2.7.  Definition of babel-routes

        object {
             (prefix, plen)       babel-route-prefix;
             int                  babel-route-router-id;
             int                  babel-route-neighbor;
             int                  babel-route-metric;
             int                  babel-route-seqno;
             ip address           babel-route-next-hop;
             boolean              babel-route-selected;
         }babel-routes-obj;

      babel-route-prefix: Prefix (with prefix length) for which this
      route is advertised

      babel-route-router-id: router-id of the router originating this
      prefix

      babel-route-neighbor: neighbor that advertised this route (is this
      a router-id ?)

      babel-route-metric: the metric with which this route was
      advertised by the neighbor, or FFFF hexadecimal (infinity) for a
      recently retracted route

Stark                    Expires January 4, 2018                [Page 6]
Internet-Draft           Babel Information Model               July 2017

      babel-route-seqno: the sequence number with which this route was
      advertised

      babel-route-next-hop: the next-hop address of this route

      babel-route-selected: a boolean flag indicating whether this route
      is selected, i.e., whether it is currently being used for
      forwarding and is being advertised

3.  Acknowledgements

   This information model was originally derived from RFC 6126
   [RFC6126].  That model is being modified according to draft-ietf-
   babel-rfc6126bis [babel-rfc6126bis].  Juliusz Chroboczek review has
   been very helpful in refing this information model.

4.  References

4.1.  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,
              <http://www.rfc-editor.org/info/rfc2119>.

4.2.  Informative References

   [babel-rfc6126bis]
              Chroboczek, J., "The Babel Routing Protocol", Work in
              Progress, draft-ietf-babel-rfc6126bis, May 2017.

   [RFC6126]  Chroboczek, J., "The Babel Routing Protocol", RFC 6126,
              DOI 10.17487/RFC6126, April 2011,
              <http://www.rfc-editor.org/info/rfc6126>.

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

   [RFC7298]  Ovsienko, D., "Babel Hashed Message Authentication Code
              (HMAC) Cryptographic Authentication", RFC 7298,
              DOI 10.17487/RFC7298, July 2014,
              <http://www.rfc-editor.org/info/rfc7298>.

Stark                    Expires January 4, 2018                [Page 7]
Internet-Draft           Babel Information Model               July 2017

Appendix A.  Open Issues

   This draft must be reviewed against draft-ietf-babel-rfc6126bis.

   Following are some issues where a conscious decision may be useful:

      babel-self-router-id: Should this be an opaque 64-bit value
      instead of int?

      Would it be useful to define any of the following as per-interface
      constants: hello-interval-lossy, hello-interval-lossless, ihu-
      interval, update-interval, ihu-hold-time, route-expiry-time,
      garbage-collection-time, max-trigger-delay, max-normal-delay, ack-
      limit, resend-trigger-lossy-limit, resend-trigger-lossless-limit,
      resend-normal-lossy-limit, resend-normal-lossless-limit

      babel-interfaces-obj: "This needs further discussion, I fear some
      of these are implementation details."

      Would it be useful to define some parameters for reporting
      statistics or logs?

      Would it be useful to define some parameters specifically for
      security anomalies?

Author's Address

   Barbara Stark
   AT&T
   Atlanta, GA
   US

   Email: barbara.stark@att.com

Stark                    Expires January 4, 2018                [Page 8]