ISDN communication board providing advanced serviceability on PC

A new ISDN communication board with a basic rate interface for a personal computer is described. In addition to handling the telephone calls over the B-channel and packet data transfer over B or D-channels, this board has the following special functions when it is connected to the B-channels in the circuit switched mode: (1) data multiplexing into one B-channel, (2) external data input/output, (3) data ciphering, and (4) data path switching to select functions. The functions of the ISDN communication board and implementation of the special functions are described. An effective method for selecting a suitable function out of many transfer functions is also described. A network game is discussed as an application system using this board.<
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