Track 2 - Internet Routing and IP Network management (7-Oct-96)

Multicast

3) Protocols

E) Core Based Trees

  1. Join toward pre-known fixed point in network as core

  2. limits expansion of multicast transmissions to precisely the set of all recipients.

  3. Better than Reverse Path Forwarding (DVMRP)

  4. Scaling depends on number of groups (*,G) not (S,G) in DVMRP

  5. CBT using spanning tree

    (see Radia Perlman on bridges (link layer) spanning tree algorithms)

  6. CBT has problem that all traffic goes toward that core

  7. Requires Changes to IGMP (Join, Leave)

  8. CBT has pre-defined Rendezvous-point, PM defines by configuration

  9. Tony Ballardie has proposed CBT