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MPLS Loop Prevention Mechanism

The information below is for an old version of the document that is already published as an RFC.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 3063.
Authors Yoshihiro Ohba , Yasuhiro Katsube , Paul Doolan , Eric C. Rosen
Last updated 2013-03-02 (Latest revision 2000-04-27)
RFC stream Internet Engineering Task Force (IETF)
Additional resources Mailing list discussion
Stream WG state WG Document
Document shepherd (None)
IESG IESG state RFC 3063 (Experimental)
Consensus boilerplate Unknown
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A new Request for Comments is now available in online RFC libraries.

        RFC 3063

        Title:      MPLS Loop Prevention Mechanism
        Author(s):  Y. Ohba, Y. Katsube, E. Rosen, P. Doolan
        Status:     Experimental
        Date:       February 2001
        Pages:      44
        Characters: 93523
        Updates/Obsoletes/SeeAlso:    None        

        I-D Tag:    draft-ietf-mpls-loop-prevention-03.txt


This paper presents a simple mechanism, based on "threads", which
can be used to prevent Multiprotocol Label Switching (MPLS) from
setting up label switched path (LSPs) which have loops.  The
mechanism is compatible with, but does not require, VC merge.  The
mechanism can be used with either the ordered downstream-on-demand
allocation or ordered downstream allocation.  The amount of
information that must be passed in a protocol message is tightly
bounded (i.e., no path-vector is used).  When a node needs to change
its next hop, a distributed procedure is executed, but only nodes
which are downstream of the change are involved.

This document is a product of the Multiprotocol Label Switching
Working Group of the IETF.

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.

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