Internet telephony uses the Internet to send audio between two or more computer users in real time, so the users can converse. Typically, a user on one end speaks into her computer's microphone and listens via her computer's speakers, while the user on the other end speaks into his regular telephone. This technology has improved to a point where conversations are easily possible. And it continues to get better. Companies have introduced products to commercialize the technology, and virtually every major telecommunications company has launched research to combat this latest threat to its market.
Gateways are the key to making Internet telephony work.
Gateways bridge the traditional circuit-switched telephony world with the Internet. Gateways bring the cost and other advantages of Internet telephony to the standard telephone, and allow users to connect with each other via their phone numbers. On one side, the gateway connects to the telephone world. It can communicate with any phone in the world. A phone line plugs into the gateway on this end.