Internet Telephony

IP-enabled PBXes will let you make long-distance calls for the the cost of two local connections.

Bob Emmerson

Internet telephony is becoming a more serious business tool as it merges with traditional PBXes. These Internet gateway switches are creating a new market that will be worth $560 million by 1999, according to International Data Corp. Products in this area divide into intracompany systems that create an overlay voice/fax network on top of an enterprise IP data network and systems that can forward IP calls over the standard telephone network and use the Internet as a backbone.

Micom Communications' (Farnham, U.K.) V/IP (voice over IP) gateway, for example, is a PC card that goes into a server and sits between the PBX and the IP network. It let s you send phone calls and faxes over the same IP network that carries the regular data traffic.

In the meantime, companies such as Innomedia (Singapore) are developing switches that let you make long-distance calls for the cost of two local connections. Innomedia's InfoGate Internet PBX, which will be available this summer, has four internal extension lines, four outside lines to Public Switched Telephone Network (PSTN), and one ISDN line to the Internet service provider (ISP). Internet telephony can be initiated either from one of the four internal lines or by an outside party calling into the gateway.

InfoGate digitizes and compresses calls, puts voice into IP packets, and sends packets to a remote InfoGate via the Internet. At the remote site, a phone call can terminate at one of the four internal lines, or you can transfer it over the public infrastructure using one of the external lines.

This is the baseline functionality. However, if the Internet is congested and the resulting voice quality is unacceptable, or when a call has to be of circuit-switched quality, InfoGate automatically puts the call through ISDN.

---

Internet PBX Connections

illustration_link (27 Kbytes)

InfoGate provides telephone services via the Internet or PSTN.