VoIP for business: call anytime anywhere for less.

• Author: Colby, Kent L.

STARTED WITH ALEXANDER

The telephone system is a part of life, and has been since Alexander Graham Bell invented it in 1876. Now, with the advent of the Internet, the communications traveling over the "plain old telephone system," or POTS, and the IP network are merging. Existing data network infrastructure can handle phone or voice calls. This increasingly popular technology is called Voice over IP (VoIP).

Already the acronym is clouded. David Morris, spokesperson for Alaska's GCI, says, "We define VoIP as voice traffic that goes through a packet-switched telecommunications network. It is under constant scrutiny of regulatory bodies. It has a variety of quality of service levels, may or may not support E911, may or may not pay network access fees, etc.

"It can be confusing because we carry voice traffic using IP today; when we hook up a local telephone customer with our cable plant-and while it is technically VoIP it is not what's commonly--and most of the time confusingly--referred to as VoIP in popular media.

"IP Telephony, on the other hand, is generally used by large businesses with several locations. While it is still packet switched like VoIP, because it is an internal enterprise application, it is not subject to the FCC, RCA, etc. It does provide a good amount of flexibility and reduced costs."

In considering VoIP, think of it as digitizing the analog voice signal and sending out the voice traffic over the data network. As a telephone call can now travel over a company's network lines or the public network--the Internet--there are no long-distance charges.

IP telephony uses the data network within the company to replace the Private Branch Exchange (PBX) with digital technology, thereby generating dial tone, signaling, gatekeeping and switching within a company. It interfaces with the public-switched telephone network, or CO (Central Office), using call agents, such as the Cisco CallManager product to manage the system. IP phones look like, feel like and sound like a standard telephone, but use Internet Protocol (IP) to digitize and send the voice signal digitally along its merry way over the data network.

For both the professional or those who dabble in data networking and telephony who are looking for a good read to help digest a solid foundation of VoIP, check out the book "Voice over IP First-Step." The published work provides a clear introduction to the world of VoIP networks. The concepts are presented in plain language, so you...