US Patent 7639682 Communication quality management and apparatus

A server proxy (12), which is arranged between a distribution server (11) and a router (13a), adds quality information to a packet (19a) from the distribution server (11) to output a packet (19b). A plurality of reception terminal proxies (17a-17n), which are arranged immediately before respective reception terminals (18a-18n), remove the quality information from the packet (19b) distributed via a network (14) and routers (13b-13m), and distribute only necessary information to the respective reception terminals (18). Each reception terminal proxy (17) which includes a quality information acquisition unit (17A) acquires the quality information to transmit, from a quality information calculation/transmission unit (17B), the quality information (51) to an accumulation server (15). The accumulation server (15) saves, in a quality information database, packet quality information (52) for each reception terminal (18).