Special Edition Using TCP/IP, Second Edition

The Need for Voice Over IP

To understand the importance of Internet Protocol (IP), you must first consider two essential aspects of telephony. For the more than one-hundred years since Alexander Graham Bell called out to his assistant and discovered his invention worked, people have become accustomed to communicating locally and globally through traditional means. The de facto technology that enables people to “reach out and touch someone” through a standard telephone is a circuit-switched system called Public Switched Telephone Network (PSTN). As happens easily with inventions of convenience, our culture pretty much thought that this was the only means of getting the job done. Along came the age of computers and the advancements that created ...