Chapter 11: Public Switched Telephone Network

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OVERVIEW

Ever since Alexander Graham Bell made the first telephone call, the telephone network has expanded by leaps and bounds. The technical term for the telephone network is Public Switched Telephone Network (PSTN). PSTN now interconnects the whole world to enable people to communicate using the most convenient and effective means of communication—voice.

In this chapter, we will study the architecture of the PSTN and also discuss the latest technologies being introduced in the oldest network to provide better services to telephone subscribers. The PSTN is becoming more and more digital, and hence our description of the PSTN is oriented toward digital technology.

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