What is an ISDN2 Line?

ISDN2 lines come in pairs that are often called channels. This means that with 1 ISDN2 line you can make 2 simultaneous calls. It also offers DDI Numbers (Direct Dial Numbers.) These can be purchased in blocks of 10 numbers so that individuals or departments can have an direct telephone number. Lots of companies will also use these if they have a marketing campaign so that they can see what response they are getting.
ISDN2 lines are also used to send data and for video conferencing. Despite the fact that they will only give you 64k on a single channel, and 128k with a dual channel, you can dial directly to the place where you need your data sent. This makes the transfer more secure.
The costs are similar to single analogue lines for on-going rentals but the install charges are slightly higher. Ideally these lines are for companies that use between 2 and 8 lines.
If more lines are required then ISDN30 should be used.