The previous two articles examined VoIP using computers. Internet phone calls can also be made without a computer. A broadband Internet connection is still required but it doesn’t need to be connected to a computer to take advantage of VoIP.

This kind of system works by installing a broadband modem to a telephone or cable TV line. The modem is attached to a regular telephone with an Analog Telephone Adapter (ATA). These devices are usually provided free of charge when you sign up with a VoIP service provider.

The ATA is connected to the modem and provides the necessary hardware and software to convert your analog voice signal into compressed digital data. The person receiving the call does not need any special equipment and will have no indication that you are not using PSTN (Public Switched Telephone Network). In fact, in some situations, the signal may be clearer than with land-based phone lines.

One of the great advantages of having an ATA is its portability. The ATA is a small, lightweight device that can be taken with you anywhere. Why would you want to do this? If you have access to a broadband modem anywhere in the world, you can simply plug a regular telephone into your ATA and connect it to the modem. The ATA has a unique identification number that allows people to call you no matter where in the world you are. The cost of such a call is the same no matter whether you are in Hong Kong or Toronto.

If the idea of carrying around an ATA seems cumbersome, you can buy an IP phone that combines the phone set and the ATA into one unit. IP phones are plugged into a modem and can be used to make or receive calls anywhere in the world.

As an example, suppose you are based in San Francisco and are travelling in Asia. Anybody can call your regular San Francisco phone number and their call will be routed to your IP phone in Hong Kong or Tokyo or wherever you are. If they are calling from San Francisco there are no overseas charges involved. Similarly, if you want to call someone in San Francisco, your call will be treated as a local call.

All the extra features of VoIP are available with both ATA’s and IP phones. Call waiting, call forwarding, call display, and conference calls can all be done with either an ATA or an IP phone. The cost of these services is usually included in your monthly rate - a substantial saving over similar services offered by your traditional phone company.