Call set-up process

Call setup and service invocation in telecommunications...

Call setup in a video telephony network

Call signal generating circuit

Call state processor for a time division switching system

Call status recognition in a broadband private automatic...

Call transfer in a cellular telephone network

Call transfer system

Call-for-service and continuity sensor circuit

Call-processing system and method

Call-routing method for a virtual private network as well as...

Called line status testing circuit

Calling line identification

Calling line identification system

Calling line tracing system and identification detector

Calling line tracing system and identification detector

Calling party identifying apparatus

Calling party message response method and apparatus

Calling terminal controlled call coverage

Camp-on discriminating system for automatic telephone exchange