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        RFC 2201:  

        Title:      Core Based Trees (CBT) Multicast Routing
		    Architecture
	Author:     A. Ballardie
        Category:   Experimental
	Date:       September 1997
        Mailbox:    ABallardie@acm.org
        Pages:      15
        Characters: 38040
        Updates/Obsoletes:  None


        URL:        ftp://ds.internic.net/rfc/rfc2201.txt


CBT is a multicast routing architecture that builds a single delivery
tree per group which is shared by all of the group's senders and
receivers.  Most multicast algorithms build one multicast tree per
sender (subnetwork), the tree being rooted at the sender's subnetwork.
The primary advantage of the shared tree approach is that it typically
offers more favourable scaling characteristics than all other
multicast algorithms.
 
The CBT protocol [1] is a network layer multicast routing protocol
that builds and maintains a shared delivery tree for a multicast
group.  The sending and receiving of multicast data by hosts on a
subnetwork conforms to the traditional IP multicast service model
[2].

This document is a product of the IDMR Working Group of the IETF.

This memo defines an Experimental Protocol for the Internet
community.  This memo does not specify an Internet standard of any
kind.  Discussion and suggestions for improvement are requested.
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Joyce K. Reynolds and Alegre Ramos
USC/Information Sciences Institute