Date Added: Jun 2009
ISDN is a digital communications network providing transmission rates in multiples of 64kbits per second. Typically described as 2B + D, Basic Rate ISDN (BRI) logically uses 2 64 kbit/s data channels (B channels) and one 16 kbit/s signalling channel (D channel). ISDN has yet to become a single global standard although within Europe EURO-ISDN is used almost exclusively. Individual countries however, have their own flavours of ISDN all of which are based to a varying degree around the ITUs ISDN standard.