Modern Telephone Systems

Facilities Available
ISDN
How ISDN works
Uses for ISDN
Advantages of ISDN
Limitations of ISDN
ADSL
   

"With a telephone and a wife a man ought to hear all that's going on!"

Danbury News, August 1877

The telephone system has been around for more than a 130 years. and the basic service it provides has not changed - it allows people to talk to one another across any distance.

But over time certain improvements have been made.

bulletLong distance calls are far cheaper now thanks to satellite systems and fibre optic cables being laid across the ocean floors that can handle tens of thousands of calls.

 

bulletIt has become automated (computerised) - the 'operator' used to be a vital part of the chain for making non-local calls. There is still an operator available, but normally they are called upon to do non-standard services such as 'reverse-charging'.

 

Computerised exchange

 

bulletYou can make a call from almost anywhere because you can connect to the system in many ways:-

'Landline' standard telephone

Payphones

Mobile Phones

Through the internet

Aircraft

Ships

 

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