Is it a passing fad or is voice-over Internet protocol (VoIP) here to stay? According to recent research, the technology is, and will remain, a viable option for companies trying to cut telecom costs.

The revolution has already swept through big corporations. Nearly 90% of large companies recently surveyed expect to use VoIP technologies within three years, according to research and consulting firm Meta Group ( , in Stamford, Conn. Ernst & Young already uses an IP phone system from Cisco Systems to connect 4,300 employees in the company's New York offices and 900 more in Houston, and expects to extend the technology to more of its 84,000 employees worldwide.

Worldwide revenues from Internet voice technologies are expected to grow from about $13 billion in 2002 to nearly $197 billion by 2007, according to Insight Research Corp., ( in Boonton, N.J. In terms of usage, VoIP customers spent more than 8.3 billion minutes on local calls alone in 2001, according to Probe Research Inc., ( http: // in Cedar Knolls, N.J. The telecom-Internet research firm projects that the number of minutes will reach 823 billion in just five years.