ISDN

Integrated Services Digital Network

Basically a digital phone line. ISDN is also commonly known by other names such as Home Highway, ISDN2e, ISDN30, Business Highway and other proprietary names. The most common types of service are ISDN2e - Home or Business Highway. Here there are 2 "channels", each of which may be used for either phone calls or internet access at 64Kb/s. It is possible therefore to use the internet at the same time as making or receiving a phone call, to make and receive a phone call simultaneously, or alternatively to double up the internet connection to 128Kb/s. It should be noted however that only 2 tasks can be performed simultaneously, so doubling up internet access to 128Kb/s would mean that phone calls cannot be made or received. It is also important to realise that you are making 2 separate phone calls and the cost per minute is therefore double the normal rate.