Call forwarding system

Call forwarding system for doorbell/intercom box

Call forwarding techniques using smart cards

Call handling for incoming telephone calls

Call handling method for credit and fraud management

Call handling systems and methods

Call hold signaling

Call in-bound remote reading and data collection system

Call information output in a telecommunication network

Call interceptor

Call interceptor

Call interceptor

Call interruption between two terminals by means of a call...

Call logging notification apparatus, system and method

Call management

Call management apparatus and methods for handling calls...

Call management method responsive to network presence

Call management protocol for insufficient credit

Call management service

Call management system