From the past:
When the phones were first introduced people needed a physical link between the phones to have a conversation i.e. an interconnection between phones was necessary and also interconnection would be constructed with third party phones which caused congestion in big cities. This process became easier when switching centers were started. The local switching centers were connected to make a multi point network and the size of the network grew enormously it became the Public Switched Telephone Network (PSTN) which we still use where it is become possible for us to make calls from any point of the world to any part of the world.
MERITS AND DEMERITS OF VOIP TECHNOLOGY:
a) Economical: It was mentioned earlier that VoIP to VoIP phone calls are free of cost. Business outsourcing has largely implemented this technology for effective communication with clientele. (VoIP info, 2004)
b) Improved functions and mobility: Now routing/ connecting international calls to a VoIP phone is made easy. Also VoIP phones can be used anywhere in the world and there will be no charges such as roaming charges. When the area of operation has network/ internet facilities a messenger can be installed and VoIP calls can be made from any computer from any location. The user has several options while using VoIP such as conference, call forward, auto redialing etc, helps reducing unnecessary work around.
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