Call queue handling

Call queuing notification

Call reception infeasibleness informing system and method

Call redirection system

Call rerouter method and apparatus

Call reservation technique for a subscriber of another exchange

Call return telephone service

Call routing control using call routing scripts

Call routing control using call routing scripts

Call routing system and method of using the same

Call scheduling in a telephone network using a telephony...

Call scheduling on a telephone network using a telephony...

Call screening agent

Call screening apparatus and method

Call screening apparatus and method

Call screening method and apparatus

Call screening system

Call set-up by an intelligent network

Call setup using a packet-switched address such as an...

Call setup using a packet-switched address such as an...