Patent ID: 7848324

Claim:
A signal processing control method of an Internet group membership protocol network device in an Internet protocol digital broadcasting system, the method comprising: when an Internet group membership protocol packet is received from an Internet group membership protocol client at a packet transmission and reception unit included in the Internet group membership protocol network device which comprises the packet transmission and reception unit for transmitting and receiving data packets and a host for processing data packets, determining, at the packet transmission and reception unit, whether or not said received Internet group membership protocol packet is to be transmitted to an upper Internet group membership protocol network device via bypass without passing through the host; when it is determined that said Internet group membership protocol packet received from said Internet group membership protocol client is to be transmitted via bypass, copying, at said packet transmission/reception unit, said received Internet group membership protocol packet, and transmitting the original Internet group membership protocol packet received from the Internet group membership protocol client to the upper Internet group membership protocol network device without passing through the host; transmitting, at said packet transmission and reception unit, the copied Internet group membership protocol packet to the host; and receiving, at said host, said Internet group membership protocol packet transmitted from said packet transmission and reception unit, processing said Internet group membership protocol packet, and simultaneously updating a multicast table of said host and a multicast table of said packet transmission and reception unit.