[rfc-dist] RFC 5520 on Preserving Topology Confidentiality in Inter-Domain Path Computation Using a Path-Key-Based Mechanism

rfc-editor@rfc-editor.org rfc-editor at rfc-editor.org
Tue Apr 28 16:54:56 PDT 2009

A new Request for Comments is now available in online RFC libraries.

        RFC 5520

        Title:      Preserving Topology Confidentiality in Inter-Domain 
                    Path Computation Using a Path-Key-Based Mechanism 
        Author:     R. Bradford, Ed.,
                    JP. Vasseur, A. Farrel
        Status:     Standards Track
        Date:       April 2009
        Mailbox:    rbradfor at cisco.com, 
                    jpv at cisco.com, 
                    adrian at olddog.co.uk
        Pages:      19
        Characters: 43125
        Updates/Obsoletes/SeeAlso:   None

        I-D Tag:    draft-ietf-pce-path-key-05.txt

        URL:        http://www.rfc-editor.org/rfc/rfc5520.txt

Multiprotocol Label Switching (MPLS) and Generalized MPLS (GMPLS)
Traffic Engineering (TE) Label Switched Paths (LSPs) may be
computed by Path Computation Elements (PCEs).  Where the TE LSP
crosses multiple domains, such as Autonomous Systems (ASes), the
path may be computed by multiple PCEs that cooperate, with each
responsible for computing a segment of the path.  However, in some
cases (e.g., when ASes are administered by separate Service
Providers), it would break confidentiality rules for a PCE to
supply a path segment to a PCE in another domain, thus disclosing
AS-internal topology information.  This issue may be circumvented
by returning a loose hop and by invoking a new path computation
from the domain boundary Label Switching Router (LSR) during TE
LSP setup as the signaling message enters the second domain, but
this technique has several issues including the problem of
maintaining path diversity.

This document defines a mechanism to hide the contents of a
segment of a path, called the Confidential Path Segment (CPS).  The
CPS may be replaced by a path-key that can be conveyed in the PCE
Communication Protocol (PCEP) and signaled within in a Resource
Reservation Protocol TE (RSVP-TE) explicit route object.  

This document is a product of the Path Computation Element Working Group of the IETF.

This is now a Proposed Standard Protocol.

STANDARDS TRACK: 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.

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