True. However, allow me to make two assumptions (true in our case): 1) Bridge implements set_multicast_list() and uses it to learn multicast groups. 2) IPv4 or IPv6 is attached to bridge - both provide IGMP snooping which in turn feeds bridge with multicast lists through set_multicast_list(). With both above assumptions true, bridge now has awareness of which ports belong to which multicast groups, hence removing the need to flood all ports. Am I getting something wrong? Tomo > -----Original Message----- > From: Guillermo Ibáñez > > Just an explanation to distinguish processing of layer 3 multicast > packets (by routers) from layer 2 multicast frames (by > bridges). Due to > the fact that the multicast MAC addresses are not permitted in the > Ethernet frame as source addresses, multicast MAC addresses > can not be > learnt by the bridges, so the processing of multicast addresses by > bridges consists in broadcasting, flooding frames in all but source > port, instead of forwarding them only by ports where these addresses > were learnt. > Excuse me if it sounds a bit "academic". > GI
