"drp" and "drpc"
1 x n communication system for private branch exchange
3 to 10 port conference circuit
3-port conference circuit for use in private automatic...
800 number call back
A call recording system and method for use with a telephone...
A call redirection system
A caller id system
A caller name and identification communication system with...
A circuit arrangement for providing internet connectivity to...
A circuit arrangement for the subscriber-remote termination...
A circuit to provide backup telephone service for a multiple...
A circuit to provide backup telephone service for a multiple...
A client-server network for managing internet protocol voice...
A coding technique in discrete multi-tone (dmt) based...
A communication apparatus having foldable and turnable...
A communication network and devices for text to speech and...
A communication system
A communication system architecture
A communication system architecture