[rfc-dist] RFC 6601 on Generic Connection Admission Control (GCAC) Algorithm Specification for IP/MPLS Networks

rfc-editor at rfc-editor.org rfc-editor at rfc-editor.org
Mon Apr 30 10:50:12 PDT 2012

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        RFC 6601

        Title:      Generic Connection Admission Control (GCAC) 
                    Algorithm Specification for IP/MPLS Networks 
        Author:     G. Ash, Ed.,
                    D. McDysan
        Status:     Experimental
        Stream:     IETF
        Date:       April 2012
        Mailbox:    gash5107 at yahoo.com, 
                    dave.mcdysan at verizon.com
        Pages:      34
        Characters: 82005
        Updates/Obsoletes/SeeAlso:   None

        I-D Tag:    draft-ash-gcac-algorithm-spec-04.txt

        URL:        http://www.rfc-editor.org/rfc/rfc6601.txt

This document presents a generic connection admission control (GCAC)
reference model and algorithm for IP-/MPLS-based networks.  Service
provider (SP) IP/MPLS networks need an MPLS GCAC mechanism, as
one motivational example, to reject Voice over IP
(VoIP) calls when additional calls would adversely affect calls
already in progress.  Without MPLS GCAC, connections on congested
links will suffer degraded quality.  The MPLS GCAC algorithm can be
optionally implemented in vendor equipment and deployed by service
providers.  MPLS GCAC interoperates between vendor equipment and
across multiple service provider domains.  The MPLS GCAC algorithm
uses available standard mechanisms for MPLS-based networks, such as
RSVP, Diffserv-aware MPLS Traffic Engineering (DS-TE), Path Computation
Element (PCE), Next Steps in Signaling (NSIS), Diffserv, and OSPF.
The MPLS GCAC algorithm does not include aspects of CAC that might be
considered vendor proprietary implementations, such as detailed path 
selection mechanisms.  MPLS GCAC functions are implemented in a distributed
manner to deliver the objective Quality of Service (QoS) for specified
QoS constraints.  The objective is that the source is
able to compute a source route with high likelihood that via-elements
along the selected path will in fact admit the request.
In some cases (e.g., multiple Autonomous Systems (ASes)), this objective
cannot always be met, but this document summarizes methods that partially 
meet this objective.  MPLS GCAC is applicable to any service or flow that 
must meet an objective QoS (delay, jitter, packet loss rate) for a 
specified quantity of traffic.  This document defines an Experimental 
Protocol for the Internet community.

EXPERIMENTAL: 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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