Note that the following refers to the use of the Alcatel USB router, which BT supply to connect the computer to the ADSL socket. An alternative is to use a separate router that is connected to the ADSL socket and provides network ports (RJ45) for networked computers.

If you have a PC, it must have a USB port to connect to the USB modem for the home USB service. Business users will need to have a network card to connect to the RJ45 connector on the modem.
The USB router does not require an electrical outlet for power that is taken from the computer's USB port. Your PC must have a USB port that can provide a constant 500mA of power for the router. In addition, some USB cards can not do so, including the 2 Port USB CMD Chipset Bus Port PCI Card. A USB card that does work is provided by Belkin. Check that it is DSL-compatible before you purchase.
You will need to have a CD-ROM drive to install the Alcatel USB router driver, which is sent to you on a CD in the 'Welcome Pack'. Alternatively you can downloading the driver and install it from your hard disk.

If you wish to connect the PC on a USB ADSL line to other computers on a local network, it will have to have a network card set aside for this function.
The computer to be used for an USB ADSL connection is usually running Microsoft Windows 98, Millennium (ME), Windows 2000 Professional, Windows 2000 Server or Windows XP, which support the USB port.

It is also possible to use Linux on the computer connected with a Linux driver for the Alcatel ADSL router. It is necessary to use a version of Linux that has kernel v 2.2 and later, that supports USB. These include the SuSE, Mandrake and Debian distributions of Linux. There is a page of useful links.