Shipments of Internet-based telephones are expected to jump 43 percent this year, reflecting how Internet telephony is becoming firmly established in companies, a market research firm said Thursday.

Shipments of Internet protocol phones is expected to reach 6.6 million units this year from 4.6 million units last year, In-Stat/MDR said.

The increasing number of Internet telephony phones reflects how businesses are embracing the technology to cut the use of traditional telephone services, which are considerably more expensive and provide fewer services, In-Stat analyst Keith Nissen said.

"VoIP (voice of Internet protocol) technology has really matured, so a service provider can provide a voice-grade service of the same quality that you would normally have (with traditional service)," Nissen said.

Telephone companies' digital subscriber lines (DSL) are available for small business to use for Internet telephony, while large businesses are gradually moving their telecommunications over to their already established IP networks.

Cost savings, as well as the ability to provide email, voice mail, instant messaging, voice communications and data services on one network, are among the key drivers behind the growing VoIP market, Nissen said.

"All of these things are really driving the market for VoIP in the enterprise, and it's really starting to move downstream to smaller companies," he said.