Integrated Services Digital Network: ISDN provides various services including Basic Rate Interface or BRI. BRI is composed of three distinct channels over 1 telephone line. 2 Bearer, or B, channels can carry digitized voice or data at the rate of 64 kbits/second. The two B channels can be combined to provide 128 kbits per second service (roughly 13 times faster than a fax transmission).
The signalling channel or D channel carries signals form the network including incoming voice or data calls. Using "Out of Band" signalling techniques, a computer can receive news of an incoming voice or data call via ISDN even if both B channels are busy.
SwitchBoard7 is the first software to utilize the D channel to its full potential - signaling the application of incoming data, voice, or fax calls. SwitchBoard7 signaling also operates while you are browsing the Internet. SwitchBoard7 and its included browser, Webstir, will utilize the technical advances of the next generation of ISDN adapters from 3Com.