05604737 is referenced by 275 patents and cites 5 patents.

A voice communication system, which is connected to a LAN to which communication terminals are connected and to a public network to which telephones are connected, is provided with a communication server between the LAN and public network having different protocols from each other. The communication server enables a voice communication between a telephone on the public network and a communication terminal connected to the LAN by performing processing similar to that for a voice communication between two communication terminals connected to the LAN. The communication server determines whether an address of the other party inputted by a user is a communication terminal address or a telephone number, and transmits a voice communication request to a communication terminal of the other party when the address is a communication terminal address. When the address is a telephone number, the user acquires the communication terminal address of the communication server, and transmits a voice communication request to the communication server. Thereafter, the voice communication processing is performed through the communication server.

Title
Voice communication system and voice communication method
Application Number
8/357189
Publication Number
5604737
Application Date
December 13, 1994
Publication Date
February 18, 1997
Inventor
Keiko Takahara
Kawasaki
JP
Susumu Matsui
Machida
JP
Naoko Iwami
Machida
JP
Agent
Fay Sharpe Beall Fagan Minnich & McKee
Assignee
Hitachi
JP
IPC
H04L 12/56
View Original Source