Basics of ISDN

ISDN

Integrated Services Digital Network 

• ISDN is a set of communication standard for digital transmission of voice ,data ,video and other network services over traditional circuits of PSTN [public Switched telephone Network] . 
•  ISDN provides a complete digital interface between end-users over twisted pair telephone lines. 
•  ISDN provides two distinct kinds of signaling components to end-users in a telecommunication network, 1st one supports traffic between end-user and network [Access signaling] and 2nd is Network signaling and is governed by SS7 suite of protocols.
• ISDN is a circuit switched telephone network system, that also provides access to packet switched networks and is designed to allow digital transmission of voice and data over ordinary telephone copper wires, which enhances better voice quality.

Benefits:

• Carries a variety of user traffic signals, including data, voice, and video.
• Offers much faster call setup than modem connections.
• The Channel A provides 4khz analogue signal. 
• B channels provide a faster data transfer rate than modems.
• B channels are suitable for negotiated Point-to-Point Protocol (PPP) links which provides a 64kbps digital channel.
• ISDN also provides more bandwidth than a traditional 56 kbps dialup connection.
• ISDN uses bearer channels, also called B channels, as clear data paths. 
• Channel H was designed as a digital channel of 384, 1,536 or 1,920 kbps that provides the user with an information transfer capability.

As per some news media, it is considered that ISDN service may be stopped from year 2020. 

-DR