Core-based trees

From Wikipedia, the free encyclopedia

Core-based trees (CBT) is a proposal for making IP Multicast scalable by constructing a tree of routers. It was first proposed in a paper by Ballardie, Francis, and Crowcroft. What differentiates it from other schemes for multicasting is that the routing tree comprises multiple "cores" (also known as "centres"). The locations of the core routers are statically configured. Other routers are added by growing "branches" of a tree, comprising a chain of routers, from the core routers out towards the routers directly adjacent to the multicast group members.


  • A. J. Ballardie; P. F. Francis; J. Crowcroft (August 1993). "Core Based Trees". ACM SIGCOMM Computer Communication Review. 23 (4): 85–95. doi:10.1145/167954.166246.
  • RFC 2189
  • Atul Vadera. "Core Based Trees (CBT)". SCAMP: SCAlable Multicast Protocol for Communication in Large Groups. Archived from the original on 2005-12-01. Retrieved 2005-12-14.