SISTEMA DE CONMUTACION Y SISTEMA DE COMUNICACION TELEFONICAQUE LO INCORPORA.

摘要

A switching system operable to establish a communication path comprising a video connection and an audio connection between stations is arranged with apparatus operable to detect the enabling of either or both said connections and further operable to control billing equipment to record the completion and duration of each such connection. Upon answer of a calling connection by a conventional telephone, audio answer supervision is returned and a corresponding billing entry is made. If the calling connection is initially or subsequently answered from a station equipped for video the concurrent presence of an audio supervision signal and a video supervision signal enables logic circuitry in the associated trunk circuits which causes the video channel to be unblocked at the called office and a combined audio-video billing entry to be made at the calling office.