PUBLIC COMMUNICATION SYSTEM COMPRISING DISTRIBUTED STATIONS, AND STATION AND SUB-STATION FOR USE IN SUCH A COMMUNICATION SYSTEM

摘要

A public communication system for encrypted audio/video information has various selective entitlement organizations with respect to its distributed receiver station. Such receiver station comprises one or more receiver sub-stations for decrypting the received encrypted information by means of a decrypting key. Furthermore, the receiver station comprises one or more decription key sub-stations that may be interrogated by the receiver sub-stations and thereupon may verify a conditional access requirement, and in case of positive verification, forward decryption key information to the interogating receiver sub-station. All said sub-stations axe interconnected by a serial standard bus, so that the configuration of a station is flexibile and may even be altered dynamically.