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Telecommunication switching systems
Evolution of Telecommunication Technology
 Today’s telecommunication technologies have evolved from the earliest smoke signals to almost instant global transmission of large amounts of data.
History
 1837- Samuel morse invents the telegraph.
 1858-Transoceanic telegraph cable is laid.
 1876-Alexander Graham bell invents telephone.
 1885-Incorporation of American telephone & telegraph company. (AT&T)
 1888-Heinrich Hertz discovers electromagnetic wave.
 1895-Marconi begins experimenting with wireless telegraphy
Telephone Terminology
 Calling Subscriber- The one who initiates the call.
 Called Subscriber- The one for whom the call is destined.
 Switching system or Exchange- A switching system is a collection of switching elements arranged and controlled in such a way as to setup a communication path between any two distant points
Need for switching systems…