CCAMP Working Group                             Wesam Alanqar (Sprint)
Internet Draft                                  Deborah Brungard (ATT)
Category: Informational                         Dave Meyer (1-4-5 Net)
                                                    Lyndon Ong (Ciena)
Expiration Date: April 2004            Dimitri Papadimitriou (Alcatel)
                                             Jonathan Sadler (Tellabs)
                                                 Stephen Shew (Nortel)

                                                          October 2003



             Requirements for Generalized MPLS (GMPLS) Routing
             for Automatically Switched Optical Network (ASON)

            draft-alanqar-ccamp-gmpls-ason-routing-reqts-00.txt



Status of this Memo

   This document is an Internet-Draft and is in full conformance with
   all provisions of Section 10 of RFC-2026.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups. Note that
   other groups may also distribute working documents as Internet-
   Drafts. 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."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.


Abstract

   The Generalized MPLS (GMPLS) suite of protocols has been defined to
   control different switching technologies as well as different
   applications. These include support for requesting TDM connections
   including SONET/SDH and Optical Transport Networks (OTNs).

   This document concentrates on the routing requirements on the GMPLS
   suite of protocols to support the capabilities and functionalities
   of an Automatically Switched Optical Network (ASON).

   *** This draft is in an early stage and propose only a template to
   be further developed ***


W.Alanqar et al. - Expires April 2004                                1

draft-alanqar-ccamp-gmpls-ason-routing-reqts-00.txt        October 2003


. Contributors

   This document is the early stage result of the CCAMP Working Group
   ASON Routing Requirements design team joint effort.

. Conventions used in this document

   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.

   The reader is also assumed to be familiar with the terminology used
   in [G.8080] and [G.7715].

. Introduction

   The GMPLS suite of protocol provides support for controlling
   different switching technologies as well as different applications.
   These include support for requesting TDM connections including
   SONET/SDH (see ANSI T1.105 and ITU-T G.707, respectively) as well as
   Optical Transport Networks (see ITU-T G.709). However, there are
   certain capabilities that are needed to support Automatically
   Switched Optical Networks (ASON) control planes. Therefore, it is
   desirable to understand the corresponding requirements for the GMPLS
   protocol suite. ASON control plane architecture is defined in
   [G.8080] and ASON routing requirements are identified in [G.7715].
   Also, the SG15/Q.14 is working on refining these requirements.

   This document focuses on the routing requirements for the GMPLS
   suite of protocols to support the capabilities and functionalities
   of ASON control planes. It discusses the requirements for GMPLS
   routing that MAY subsequently lead to additional backward compatible
   extensions to support the capabilities specified in the above
   referenced document. A description of backward compatibility
   considerations is provided in Section 5. Nonetheless, any protocol
   (in particular, routing) design or suggested protocol extensions is
   strictly outside the scope of this document. A terminology section
   (that may be further completed) is provided in the Appendix.

   The ASON model distinguishes reference points (representing points
   of protocol information exchange) defined (1) between an
   administrative domain and a user a.k.a. user-network interface
   (UNI), (2) between (and when needed within) administrative domains
   a.k.a. external network-network interface (E-NNI) and, (3) between
   areas of the same administrative domain and when needed between
   control components (or simply controllers) within areas a.k.a.
   internal network-network interface (I-NNI).

   The ASON routing architectural model is based on the following
   assumptions:

   - The information exchanged between routing controllers is subject


W.Alanqar et al. - Expires March 2004                                2

draft-alanqar-ccamp-gmpls-ason-routing-reqts-00.txt        October 2003


     to policy constraints imposed at reference points (E-NNI and I-
     NNI)

   - The routing information exchanged between routing domains (i.e.
     inter-domain) is independent of intra-domain routing protocol

   - The routing information exchanged between routing domains is
     independent of intra-domain control distribution choices, e.g.
     centralized, fully distributed

   - The routing adjacency topology and transport network topology
     shall not be assumed to be congruent

   - Each routing area shall be uniquely identifiable within a
     carrier's network (constituted by several routing domains)

   The following functionality is to be supported by GMPLS routing to
   instantiate ASON routing realization:
   - support multiple hierarchical levels
   - support hierarchical routing information dissemination including
     summarized routing information
   - support for multiple links between nodes (and allow for link and
     node diversity)
   - support architectural evolution in terms of the number of levels
     of hierarchies, aggregation and segmentation of (control ?)
     domains
   - support routing information divided between attributes pertaining
     to links and nodes (representing either a routing area or
     sub-network)

   In addition the behaviour of GMPLS routing is expected to be such
   that:
   - it is scalable with respect to the number of links, nodes and
     routing area hierarchical levels. - what does this means ? is it
     routing areas and hierarchical levels ? or hierarchical levels of
     routing areas -
   - in response to a routing event (e.g. topology update, reachability
     update), it delivers convergence and damping against flapping
   - it fulfils the operational security objectives where required

. ASON Requirements for GMPLS Routing

   The next sections detail the requirements for GMPLS routing to
   support the following ASON routing functions:
   - supporting multiple hierarchical levels
   - support hierarchical routing information dissemination including
     summarized routing information
   - support for multiple links between nodes (and allow for link and
     node diversity)
   - support architectural evolution in terms of the number of levels
     of hierarchies, aggregation and segmentation of (control ?)
     domains


W.Alanqar et al. - Expires March 2004                                3

draft-alanqar-ccamp-gmpls-ason-routing-reqts-00.txt        October 2003


   - support of routing attributes for links and nodes

4.1 Multiple Hierarchical Levels

   TBD.

4.2 Hierarchical Routing Information Dissemination

   TBD.

4.3 Multiple Links between Nodes

   TBD.

4.4 Evolution

   TBD.

4.5 Routing Attributes

   TBD.

4.5.1 Link Attributes

   TBD.

4.5.2 Node Attributes

   TBD.

. Backward Compatibility

   TBD.

. Security Considerations

   TBD.

. Acknowledgements

   The authors would like to thank Kireeti Kompella for having
   initiated the proposal of an ASON Routing Requirement Design Team.

. References

   [RFC 2026]   S.Bradner, "The Internet Standards Process --
                Revision 3", BCP 9, RFC 2026, October 1996.

   [RFC 2119]   S.Bradner, "Key words for use in RFCs to Indicate
                Requirement Levels", BCP 14, RFC 2119, March 1997.

   [G.7715]     ITU-T Rec. G.7715/Y.1306, "Architecture and


W.Alanqar et al. - Expires March 2004                                4

draft-alanqar-ccamp-gmpls-ason-routing-reqts-00.txt        October 2003


                Requirements for the Automatically Switched Optical
                Network (ASON)," June 2002.

   [G.8080]     ITU-T Rec. G.8080/Y.1304, "Architecture for the
                Automatically Switched Optical Network (ASON),"
                November 2001 (and Revision, January 2003).

. Author's Addresses

   Deborah Brungard (AT&T)
   Rm. D1-3C22 - 200 S. Laurel Ave.
   Middletown, NJ 07748, USA
   Phone: +1 732 420 1573
   E-mail: dbrungard@att.com

   Dimitri Papadimitriou (Alcatel)
   Francis Wellensplein 1,
   B-2018 Antwerpen, Belgium
   Phone : +32 3 240 8491
   E-mail: dimitri.papadimitriou@alcatel.be


































W.Alanqar et al. - Expires March 2004                                5

draft-alanqar-ccamp-gmpls-ason-routing-reqts-00.txt        October 2003


Appendix - Terminology

   This document makes use of the following terms:

   Administrative domain: See Recommendation G.805.

   Control plane: performs the call control and connection control
   functions. Through signaling, the control plane sets up and releases
   connections, and may restore a connection in case of a failure.

   (Control) Domain: represents a collection of entities that are
   grouped for a particular purpose. G.8080 applies this G.805
   recommendation concept (that defines two particular forms, the
   administrative domain and the management domain) to the control
   plane in the form of a control domain. The entities that are grouped
   in a control domain are components of the control plane.

   External NNI (E-NNI): interfaces are located between protocol
   controllers between control domains.

   Internal NNI (I-NNI): interfaces are located between protocol
   controllers within control domains.

   Link: See Recommendation G.805.

   Management plane: performs management functions for the Transport
   Plane, the control plane and the system as a whole. It also provides
   coordination between all the planes. The following management
   functional areas are performed in the management plane: performance,
   fault, configuration, accounting and security management

   Management domain: See Recommendation G.805.

   Transport plane: provides bi-directional or unidirectional transfer
   of user information, from one location to another. It can also
   provide transfer of some control and network management information.
   The Transport Plane is layered; it is equivalent to the Transport
   Network defined in G.805.

   User Network Interface (UNI): interfaces are located between
   protocol controllers between a user and a control domain.













W.Alanqar et al. - Expires March 2004                                6

draft-alanqar-ccamp-gmpls-ason-routing-reqts-00.txt        October 2003


Full Copyright Statement

   "Copyright (C) The Internet Society (2003). All Rights Reserved.

   This document and translations of it may be copied and furnished to
   others, and derivative works that comment on or otherwise explain it
   or assist in its implementation may be prepared, copied, published
   and distributed, in whole or in part, without restriction of any
   kind, provided that the above copyright notice and this paragraph
   are included on all such copies and derivative works. However, this
   document itself may not be modified in any way, such as by removing
   the copyright notice or references to the Internet Society or other
   Internet organizations, except as needed for the purpose of
   developing Internet standards in which case the procedures for
   copyrights defined in the Internet Standards process must be
   followed, or as required to translate it into languages other than
   English.

   The limited permissions granted above are perpetual and will not be
   revoked by the Internet Society or its successors or assigns.

   This document and the information contained herein is provided on an
   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.



























W.Alanqar et al. - Expires March 2004                                7