Patent ID: 7830802

Claim:
A method for preventing IP multicast data stream from overloading communication system by distinguishing multiple services, comprising the following steps of: (a1) a multicast data packet ‘packet(key)’ with a key value of ‘key’ reaching a forwarding layer and not finding a matching multicast route entry, then up sending the multicast data packet ‘packet(key)’ to a protocol processor; (a2) driving a protocol state machine to generate a multicast route forwarding entry M(key) by a protocol layer according to the multicast data packet received; meanwhile, searching for a current-limiting policy corresponding to the ‘key’ in configured multicast current-limiting policies by the forwarding layer, generating a temporary forwarding route entry T_M(key), and limiting current of subsequent multicast data packets ‘packet(key)’ by using said temporary forwarding route entry T_M(key) generated; (a3) if the protocol layer being able to generate a normal forwarding entry M(key) with a value of ‘key’, synchronizing this entry to the forwarding layer, the forwarding layer updating T_M(Key) with M(Key), and entering into a normal forwarding; otherwise, the forwarding layer continuing to limit the current according to the current-limiting policy attached by the T_M(Key), and deciding when to end the current limiting.