RFC 3031 (rfc3031) - Page 1 of 61


Multiprotocol Label Switching Architecture



Alternative Format: Original Text Document



Network Working Group                                           E. Rosen
Request for Comments: 3031                           Cisco Systems, Inc.
Category: Standards Track                                 A. Viswanathan
                                                  Force10 Networks, Inc.
                                                               R. Callon
                                                  Juniper Networks, Inc.
                                                            January 2001


               Multiprotocol Label Switching Architecture

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2001).  All Rights Reserved.

Abstract

   This document specifies the architecture for Multiprotocol Label
   Switching (MPLS).

Table of Contents

   1          Specification  ......................................   3
   2          Introduction to MPLS  ...............................   3
   2.1        Overview  ...........................................   4
   2.2        Terminology  ........................................   6
   2.3        Acronyms and Abbreviations  .........................   9
   2.4        Acknowledgments  ....................................   9
   3          MPLS Basics  ........................................   9
   3.1        Labels  .............................................   9
   3.2        Upstream and Downstream LSRs  .......................  10
   3.3        Labeled Packet  .....................................  11
   3.4        Label Assignment and Distribution  ..................  11
   3.5        Attributes of a Label Binding  ......................  11
   3.6        Label Distribution Protocols  .......................  11
   3.7        Unsolicited Downstream vs. Downstream-on-Demand  ....  12
   3.8        Label Retention Mode  ...............................  12
   3.9        The Label Stack  ....................................  13
   3.10       The Next Hop Label Forwarding Entry (NHLFE)  ........  13
   3.11       Incoming Label Map (ILM)  ...........................  14



Rosen, et al.               Standards Track