Patent ID: 6597703
Filing Date: 2003-07-22
Classification: H04L

Abstract:
In a multicast routing device having a multicast routing information base (MRIB) defining a number of enclosing ranges for multicast routes, each enclosing range characterized by a lower boundary and an upper boundary, a method for reducing the number of forwarding states maintained by the multicast routing device, each forwarding state including a source address (S), a group address (G), an inbound list identifying preferred and rejected inbound interfaces for the forwarding state, and an outbound list identifying outbound interfaces for the forwarding state, the method comprising:associating with each forwarding state a source address range encompassing at least one source address, wherein a forwarding state having a source address range encompassing all possible source addresses is a default forwarding state, and a forwarding state having a source address range encompassing fewer than all possible source addresses is a non-default forwarding state; and maintaining the forwarding states such that the source address ranges for all non-default forwarding states are non-overlapping.