RFC 3037 (rfc3037) - Page 1 of 7
LDP Applicability
Alternative Format: Original Text Document
Network Working Group B. Thomas
Request for Comments: 3037 Cisco Systems, Inc.
Category: Informational E. Gray
Zaffire, Inc.
January 2001
LDP Applicability
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2001). All Rights Reserved.
Abstract
Multiprotocol Label Switching (MPLS) is a method for forwarding
packets that uses short, fixed-length values carried by packets,
called labels, to determine packet nexthops. A fundamental concept
in MPLS is that two Label Switching Routers (LSRs) must agree on the
meaning of the labels used to forward traffic between and through
them. This common understanding is achieved by using a set of
procedures, called a label distribution protocol, by which one LSR
informs another of label bindings it has made. This document
describes the applicability of a set of such procedures called LDP
(for Label Distribution Protocol) by which LSRs distribute labels to
support MPLS forwarding along normally routed paths.
1. LDP Applicability
A label distribution protocol is a set of procedures by which one
Label Switching Router (LSR) informs another of the meaning of labels
used to forward traffic between and through them.
The MPLS architecture allows for the possibility of more than a
single method for distributing labels, and a number of different
label distribution protocols are being standardized. Existing
protocols have been extended so that label distribution can be
piggybacked on them, and new protocols have been defined for the
explicit purpose of distributing labels.
Thomas & Gray Informational