Destination device order billing according to call recipient
Detecting high usage telecommunications lines
Detecting possible fraudulent communication usage
Device for collecting, processing, working, and managing...
Devices for delivering information on their communications to su
Dial unit detachably mounted on public telephone for equal acces
Dial-around compensation method and system
Dialing plan service including outgoing call screening,...
Differentiated threshold value behavior in prepaid services
Direct distance dialing (DDD) access to a communication...
Display control device allowing information transmission to both
Distributed automatic route selection using RIP caching
Domestic origination to international termination country...
Domestic to country call intercept process (CIP)
Drive-in restaurant credit-card transaction system
Dual channel ISDN terminal call identification and switching sys
Dynamic carrier selection
Dynamic charging for telecommunications services in accordance w
Dynamic individual phone rates
Electronic surveillance in a public switched telephone network