Internet access terminology can be very confusing, especially if you’re trying to choose a new ISP. Each technology has its differences and some may be better at certain tasks than others, consequently it is important for consumers to understand the advantages and disadvantages of each prior to choosing a provider. This page seeks to explain the methods using simple language and is best used in conjunction with our 'Jargon Buster' section.

Integrated Services Digital Network (ISDN) initially works in a similar way to Dialup by connecting via a standard copper based telephone line. However unlike dialup, ISDN is almost entirely digital and able to send information at speeds of up to 64Kbps downstream and upstream. This can be increased to 128Kbps using a second channel via an additional telephone line, otherwise known as ‘bonding’.

Sadly the technology often required a line to be converted from analogue to digital and two channels were needed for maximum speed, incurring additional costs. ISDN’s advantages were that it ran through a stable and highly reliable digital network, meaning that you always got the performance expected; though ISP congestion could still hamper quality.

BT's consumer grade ISDN products (HomeHighway, Midband) could also connect to dialup ISP's. Related ISPreview Sections:
    Dialup/ISDN ISP Listings - Unmetered (Free Calls)
    Dialup/ISDN ISP Listings - Local Call Rate
    Dialup/ISDN Reader ISP Reviews
    Dialup/ISDN ISP Discussion Forum