| 摘要 |
A method of controlling communication between a head-end system (1-6) and a number of client systems (13,22) through a network (7),
wherein, for each receiver, only a nearest one of the multicast router systems (35-38) in the network is configured to forward a copy of a message addressed to the multicast groups of which the receiver is a member directly to the receiver, which method includes: maintaining subscriber group information linking each registered one of the number of client systems to an associated one of a plurality of subscriber groups; allocating registered client systems to at least one multicast group, such that all client systems associated with a particular subscriber group are in a common multicast group; obtaining information uniquely identifying the nearest multicast router system nearest to a receiver for a first client system, and assigning the first client system to a subscriber group including at least one further client system having the same nearest multicast router system. |
