SET-TOP BOX

摘要

For interactive services, for example video-on-demand, a return channel must be made available to each subscriber. The video and audio signals of an interactive service are transmitted by a server (SERVER) through a cable television network (CATV) or a satellite link to the set-top-boxes (STB) of the subscribers. The return channel is part of an integrated services digital network (ISDN). The set-top-box (STB) of each subscriber has an S0 interface (S0) through which it accesses the ISDN network (ISDN). The service request signals are transmitted by the set-top-box (STB) to the server (SERVER) in a signalling channel of the ISDN network by a packet-transmission process. The set-top-box (STB) can also receive control signals from the ISDN network. Moreover, multiplexing of several signalling channels is provided in a central exchange.