Communication System Having ISDN (Integrated Services Digital Network) Signaling Capability

摘要

The present invention relates to a station terminal arranged to communicate ISDN (Integrated Services Digital Network) D channel control information in a Q.931 control protocol message over a communication facility to a control unit. The terminal is comprised of a unit for receiving information over the facility from the control unit, the information being received in a local protocol message format having a first group of information elements. The elements include a first group of control information elements that contain mandatory elements of the Q.931 protocol messages for controlling a call setup at station terminal and a second group of control information elements that are derived from a third group of information elements selected from one or more sets of information elements. The information elements include a first set of non-mandatory Q.931 protocol message information elements and a second set of local information elements obtained from a data memory that is accessible by the control unit. A unit is also provided for controlling user interactions with the terminal, via the user-interface device, using the second group of control information elements.