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        RFC 2189

        Title:      Core Based Trees (CBT version 2) Multicast Routing
	Author:     A. Ballardie
        Category:   Experimental
	Date:       September 1997
        Mailbox:    ABallardie@acm.org
        Pages:      23
        Characters: 52043
        Updates/Obsoletes:  None


        URL:        ftp://ds.internic.net/rfc/rfc2189.txt


This document describes the Core Based Tree (CBT version 2) network
layer multicast routing protocol. CBT builds a shared multicast
distribution tree per group, and is suited to inter- and intra-domain
multicast routing.
 
CBT may use a separate multicast routing table, or it may use that of
underlying unicast routing, to establish paths between senders and
receivers. The CBT architecture is described in [1].

This document is a product of the IDMR 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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Joyce K. Reynolds and Alegre Ramos
USC/Information Sciences Institute