Internet telephony has been around almost as long as the Web, but the technology hasn't taken off in the way of other Web-enabled applications such as text-based chatting, streaming video, and online banking. Even so, millions of people use the Web to make at least some of their telephone calls—to other PC users and to people with regular telephones.
Why would you want to make calls on your PC? The reasons include Internet telephony's flexibility, low cost, and definite coolness. Want to call someone on the other side of the country for a penny a minute (or free if they also have an Internet phone) or call Europe at a rate much cheaper than conventional phones offer? Want to add a second (or third, or fourth) phone line for peanuts or in places where you can't get more phone lines without significant cable stringing? An Internet phone lets you do all this. You can even avoid getting hit with hotel room phone charges when you travel (if your hotel room has a DSL line) by using an Internet telephone to call from your laptop.
Tiny Little Packets
According to the International Engineering Consortium (IEC), Internet telephony refers to communications services that traverse the Internet rather than the Public Switched Telephone Network (PSTN). To originate an Internet telephone call, an Internet telephony system first converts the analog voice signal to digital format, then compresses and translates the signal into IP packets for transmission over the Internet. The process is reversed at the receiving end.
In 1995—long before people took high-speed Internet connections, fast processors, and other multimedia PC capabilities for granted—a handful of software providers created programs that let users make voice calls from one computer to another computer for free. Unfortunately, both parties had to have multimedia PCs and the same software, which translated voice signal into Internet protocols. Another stumbling block for Internet telephony was that in 1995, the average modem speed was an anemic 14.4Kbps to 33.3Kbps. And the slower the Internet connection, the funkier the call sounded.
The complexity of getting started with Internet telephony and its initially poor sound quality prevented the technology from taking off the way flashier (and lower-bandwidth) Web applications have. But as broadband Internet connections such as DSL, cable modem, and satellite continue to grow in popularity, Internet telephony looks more enticing for home and small-business use, especially because you can now use your PC to make calls to conventional telephones, too.
Making the Connection
Let's explore the equipment you need to make Internet calls and some options for prepackaged Internet phones. The basic setup includes a PC, an Internet connection, Internet telephony gear (speakers and a microphone), and Internet telephony software.
System requirements. Make sure your computer has a reasonably fast processor (at least 300MHz), a decent amount of RAM (64MB is the bare minimum for Internet telephony, and Microsoft recommends a minimum of 128MB for Windows XP), a sound card, speakers, and Windows 95 or later. XP includes Windows Messenger software, which you can use to make calls from your PC to any telephone in the world by using one of several available Internet telephony providers.