What is the difference between PSTN and ISDN?Data communication and networking

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janettecoleman | (Level 1) eNoter

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PSTN  is the acronym for the public switched telephone network.

ISDN   is the acronym for integrated services digital network.


PSTN is the world's public circuit much like the Internet is the network of the world's public IP based packet switched network.  It is almost entirely digital now.  In the last couple of years digital services have been given to end users using DSL and ISDN.

The digital circuit in PSTN is a 64 kilobytes per second channel.

A large group of telephone networks aren't linked to the PSTN- such as

our military and sometimes large corporations.

PSTN was restructured in 1984 when AT&T could not have a monopoly on telecommunications any longer.

Long term users say that PSTN will be one of many applications of the Internet and to others it seems a long time period will be needed.

Some other possible links:

  1. Fixed-line analog telephone system
  2. ITU-T
  3. Reference points
  4. V5 interface
  5. QoS - quality of service
  6. Voice over IPs - Internet protocal
  7. Gateways
  8. SS7 network


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