Multicast data message forwarding method, entry router bridge, exit router bridge and multicast data message forwarding system

The invention provides a multicast data message forwarding method, an entry router bridge, an exit router bridge and a multicast data message forwarding system, and relates to the technical field of communication. The method comprises the steps that: the entry router bridge receives a multicast data message; the entry router bridge encapsulates the multicast data message to a Trill unicast data frame; and the entry router bridge forwards the Trill unicast data frame to the exit router bridge corresponding to the multicast data message. After encapsulating the received multicast data message tothe Trill unicast data frame, the entry router bridge forwards the Trill unicast data frame to the exit router bridge corresponding to the multicast data message; therefore, flooding of the multicastdata message in a Trill domain is avoided; load sharing of the multicast data message on different links can be realized; and thus, the physical bandwidth utilization rate of a Trill network is indirectly increased. 本发明提供了种组播