What is BISDN in Computer Network?

The B-ISDN (broadband integrated services digital network) is a virtual circuit-switched network that can use high-speed packet switching services. The B-ISDN will use a flexible multiplexing format called ATM (asynchronous transfer mode).

B-ISDN services are classified into interactive and distribution services. Interactive services contain the bidirectional flow of user information between two subscribers or between a subscriber and a service provider.

Interactive services

The interactive services are further divided into three sub-categories which are as follows−


Conversational service involves the real-time exchange of information such as sound, video, data or entire documents. Examples include video-telephony, video-conference, and high-speed data transfer. Video-telephony is like the normal video telephony service but also has video capture, transmission and display capabilities. Video-conference supports voice and video communication between two conference rooms or between several individuals.


Messaging service involves the non-real-time exchange of information between subscribers in a store-and-forward fashion.


Retrieval services provide subscribers with retrieval access to centrally-stored public information. Examples include broadband videotext (retrieval of video images/sequences with sound, text and graphics), video retrieval (subscriber create to video libraries of movies) and return of high-resolution pictures and records from multiple archives and data centers.

Distribution Services

Distribution services contain the unidirectional flow of user information from a service provider to a subscriber.

Distribution services are divided into two sub-categories, which are as follows:

  • Distribution services without user presentation control involve the central broadcast of information to many subscribers, where subscribers have no control over data display. Examples include the broadcast of TV programs, electronic newspapers, and electronic publishing.
  • Distribution services with user presentation control are the same as the previous category. The information is offered as cyclically repeated frames, thereby enabling the subscribers to control the start and the order of the frames presentation. Examples include electronic newspaper and tele-advertising.