Russian Dolls Bandwidth Constraints Model for Diffserv-aware MPLS Traffic Engineering
RFC 4127

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 07

Network Working Group                                F. Le Faucheur, Ed.
Request for Comments: 4127                           Cisco Systems, Inc.
Category: Experimental                                         June 2005

            Russian Dolls Bandwidth Constraints Model for
                Diffserv-aware MPLS Traffic Engineering

Status of This Memo

   This memo defines an Experimental Protocol for the Internet
   community.  It does not specify an Internet standard of any kind.
   Discussion and suggestions for improvement are requested.
   Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2005).

Abstract

   This document provides specifications for one Bandwidth Constraints
   Model for Diffserv-aware MPLS Traffic Engineering, which is referred
   to as the Russian Dolls Model.

Table of Contents

   1. Introduction ....................................................2
      1.1. Specification of Requirements ..............................2
   2. Contributing Authors ............................................3
   3. Definitions .....................................................4
   4. Russian Dolls Model Definition ..................................5
   5. Example Formulas for Computing "Unreserved TE-Class [i]" with
      Russian Dolls Model .............................................7
   6. Receiving Both Maximum Reservable Bandwidth and Bandwidth
      Constraints sub-TLVs ............................................8
   7. Security Considerations .........................................8
   8. IANA Considerations .............................................8
   9. Acknowledgements ................................................9
   Appendix A: Addressing [DSTE-REQ] Scenarios .......................10
   Normative References ..............................................11
   Informative References ............................................12

Le Faucheur                   Experimental                      [Page 1]
RFC 4127             Russian Dolls Model for DS-TE             June 2005

1.  Introduction

   [DSTE-REQ] presents the Service Providers requirements for support of
   Diffserv-aware MPLS Traffic Engineering (DS-TE).  This includes the
   fundamental requirement to be able to enforce different Bandwidth
   Constraints for different classes of traffic.

   [DSTE-REQ] also defines the concept of Bandwidth Constraints Model
   for DS-TE and states that "The DS-TE technical solution MUST specify
   at least one Bandwidth Constraints Model and MAY specify multiple
   Bandwidth Constraints Models".

   This document provides a detailed description of one particular
   Bandwidth Constraints Model for DS-TE which is introduced in
   [DSTE-REQ] and called the Russian Dolls Model (RDM).

   [DSTE-PROTO] specifies the Interior Gateway Protocol (IGP) and RSVP-
   TE signaling extensions for support of DS-TE.  These extensions
   support RDM.

1.1.  Specification of Requirements

   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 [RFC2119].

Le Faucheur                   Experimental                      [Page 2]
RFC 4127             Russian Dolls Model for DS-TE             June 2005

2.  Contributing Authors

   This document was the collective work of several authors.  The text
   and content were contributed by the editor and the co-authors listed
   below. (The contact information for the editor appears in the
   Editor's Address section.)

   Jim Boyle                               Kireeti Kompella
   Protocol Driven Networks, Inc.          Juniper Networks, Inc.
   1381 Kildaire Farm Road #288            1194 N. Mathilda Ave.
   Cary, NC 27511, USA                     Sunnyvale, CA 94099

   Phone: (919) 852-5160                   EMail: kireeti@juniper.net
   EMail: jboyle@pdnets.com

   William Townsend                        Thomas D. Nadeau
   Tenor Networks                          Cisco Systems, Inc.
   100 Nagog Park                          250 Apollo Drive
   Acton, MA 01720                         Chelmsford, MA 01824

   Phone: +1-978-264-4900                  Phone: +1-978-244-3051
   EMail: btownsend@tenornetworks.com      EMail: tnadeau@cisco.com

   Darek Skalecki
   Nortel Networks
   3500 Carling Ave,
   Nepean K2H 8E9

   Phone: +1-613-765-2252
   EMail: dareks@nortelnetworks.com

Le Faucheur                   Experimental                      [Page 3]
RFC 4127             Russian Dolls Model for DS-TE             June 2005

3.  Definitions

   For readability a number of definitions from [DSTE-REQ] are repeated
   here:

   Class-Type (CT): the set of Traffic Trunks crossing a link that is
                    governed by a specific set of bandwidth constraints.
                    CT is used for the purposes of link bandwidth