Overview of the PSTN and Comparisons to Voice over IP
The Public Switched Telephone Network (PSTN) has been evolving ever since Alexander Graham Bell made the first voice transmission over wire in 1876. But, before explaining the present state of the PSTN and what's in store for the future, it is important that you understand PSTN history and its basics. As such, this chapter discusses the beginnings of the PSTN and explains why the PSTN exists in its current state.
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