An Effective Solution for Multicast Scalability:The MPLS Multicast Tree (MMT)

Document Type Expired Internet-Draft (individual)
Author Ali Boudani 
Last updated 2004-10-11
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A multicast router should keep forwarding state for every multicast tree passing through it. The number of forwarding states grows with the number of groups. In this paper, we present a new approach, the MPLS multicast Tree (MMT), which utilizes MPLS LSPs between multicast tree branching node routers in order to reduce forwarding states and enhance scalability. In our approach only routers that are acting as multicast tree branching node routers for a group need to keep forwarding state for that group. All other non- branching node routers simply forward data packets by traffic engineered unicast routing using MPLS LSPs. We can deduce that our approach can be largely deployed because it uses for multicast traffic the same unicast MPLS forwarding scheme. We will briefly discuss the multicast scalability problem, related works and different techniques for forwarding state reduction. We discuss also the advantages of our approach, and conclude that it is feasible and promising. Finally, we analytically evaluate our approach.


Ali Boudani (

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