SATELLITE SOURCE PROTECTION SYSTEM OF MULTIMEDIA SATELLITE COMMUNICATION SYSTEM

摘要

PURPOSE: A satellite resource security system of multimedia satellite communication system is provided to prevent anyone who attempts to access database other than Internet subscriber accessing open multimedia server or a communication of a satellite subscriber. CONSTITUTION: A router(16) connects with Internet. A transmission data process unit generates transport stream(TS) packets in accordance with data, which will be transmitted to a station. A district center(1) has a processor controlling links between the district center(1) and stations. A receive data process unit restores frequency signals from the district center into original transport stream(TS) packets. The transmission data process unit performs CDMA(Code Division Multiple Access) modulation and frequency modulation to signals which will be sent out to the district center(1). Control of stations and traffic management of communication terminal are executed in accordance with transport stream(TS) packets from the receive data process unit. A processor controls and makes up return links by controlling the transmission data process unit. The router(16) in the district center(1) has all the Internet protocol(IP) address table used in the district center(1), and receives IP packets from Internet. The router(16) detects headers of the packets and searches destination IP address for invalid destination IP address and discard the packets with the invalid destination IP address.