ISDN. ISDN (Integrated Digital Services Network)

ISDN. ISDN (Integrated Digital Services Network) is a more-advanced type of dial-up connection that can transfer data up to 128Kbps, double that of a standard phone-line connection. This setup is a true digital connection, rather than the digital-analog combination of standard dial-up, allowing it to use ordinary phone wires at double the normal data transfer capacity.

The faster speed means it costs more than standard dial-up, but it's better at handling data transfers, and the true digital connection means it's more reliable than standard dial-up connections.

Many businesses use ISDN for telecommuting or remote workers who need to communicate to a business's main office. That's because ISDN give workers access to standard office communications tools, such as an Internet connection, e-mail and fax capabilities, and telephony, because it can simultaneously support voice and data transmission.

ISDN requires additional hardware beyond a standard dial-up connection. A dual telephone wire setup dedicated solely to the ISDN connection is required as well as an ISDN router in your office. (A router is a network device use to data between two or more networks). This equipment typically is installed by your local phone company.

It's also a good idea to first check with the phone company to ensure ISDN is available in your area before buying any hardware, as about 10 percent of the United States lacks ISDN service.