Call tracker
Call transfer and conference with separate billing records...
Call-accounting system
Call-connecting device, call-connecting method,...
Call-disposition analyzer
Call-processing system and method
Called party response detecting apparatus
Calling card validation system and method therefor
Calling line identification adjunct for use with a communication
Calling party-paid wireless telephone service
Calling-party-pays call processing for cellular and paging
Calling-party-pays call processing for cellular and paging
Calling-party-pays call processing for cellular and paging
Calling-party-pays call processing for cellular and paging
Centralizing storage and verification element for telephone netw
Charge information method
Charging for an IP based communication system
Charging for an IP based communication system
Charging for usage of a telecommunications network
Charging in a communication system