Integrated services Digital Network (ISDN)

An ISDN is a high speed digital communication network evolving from existing telephone line, which is called dial-up networking. Beside this connections such as ISTN (Integrated services Digital Network (IDN), which provides end- to – end digital connectivity to support a wide rang of services, including voice and non voice services. The services provided by ISDN are:

1. integrated services
2. Satellite Connection
3. Cable Connection
4. Dial up connection

Integrated Services

Digital Network is a digital circuit switching technology that carries voice, graphics and data through telephone lines. It is suitable for business and commercial use. It is at least four times faster then a dial-up line.

Satellite connection

Satellite connection can be used to connect a computer or a computer network to the internet. This is good for remote location, where ISDN and other cable connection are not available. It provides connection through satellite to the user’s disk antenna. Satellite connection is expensive but provides faster and more qualitative services then other connection.

Cable Connection

A computer connected to the internet through a cable television line is a popular connection, which provides fast and reliable services to the user. A cable modem is used to connect the computer and the cable television line. It may have two connections, one to the television and other to the computer system. Nowadays, many cable television providers offer internet connection along with television services.

Dial-up connection

Dial- up connection is the chenpast and the easiest way to connect a computer to the internet. It requires a normal telephone line and an internal or external MODEM. The performance of the dile-up connection is very low in comparison with the other connections discussed above. The above figure shows the connection of a computer to the internet using an external MODEM: