Chapter 1. Voice and Data: Two Separate Worlds?

Telephony is the communication of spoken information between two or more participants, by means of signals carried over electric wires or radio waves. Ever since Alexander Graham Bell invented the telephone circuit and first envisioned the public telephone system, consumers and businesses have relied on telephony as a staple of human interaction.

With the advent of Internet technologies and high-speed data connectivity in the enterprise, a new family of telephony technologies began taking hold. Voice over IP, or VoIP, has significant appeal for the enterprise, for service providers, and for end users, because it allows the Internet and commonplace data networks, like those at offices, factories, and campuses, to become carriers for voice calls, video conferencing, and other real-time media applications. VoIP-savvy organizations are discovering that they can apply the paradigm of distributed, software-based networking to voice applications and enable a new generation of telecommunications features, cost-savings, and productivity enhancements.