3Com AccessBuilder 500 User Manual - Benefits Of Isdn

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Benefits of ISDN

ISDN is an extension of the national and international public switched 

telephone network, which offers a digital end-to-end telecommunication 

system, providing a better quality service than available using the analog 

telephone network. The principal benefits of ISDN are:

■

Fast call setup times, typically taking less than one second for national 

calls.

■

Greater bandwidth with multiple channels.

The basic rate service, often referred to as ISDN 2, carries two 64 Kbps 

(or possibly two 56 Kpbs in USA) user channels, called B channels and 

one 16 Kbps control channel called the D channel. The line service is 

presented into the customers premises through a standard RJ45 socket. 

A significant aspect of the ISDN service is that it can be provided over 

the same wiring that was installed for the original telephone service. 

Therefore, ISDN can be made available relatively cheaply almost 

anywhere that previously had access to the analog system.

The cost of installation and rental of basic rate ISDN lines has dropped to 

the point where it is extremely attractive as regards cost and performance.