By far, the type of VOIP that is leading the charge to converged communications is Internet phone service. That's because this is the most convenient and intuitive way to use VOIP.
As shown in the figure below, Internet phone service allows you to use the telephone that you're accustomed to using, and the only thing you have to alter is the way in which the phone is plugged in. That's because this type of VOIP service works with one of three types of technology:

• ATA (analogue telephone adapter): A converter that plugs into your broadband router, which is your DSL (Digital Subscriber Line) or cable modem, that converts an analogue telephone conversation into digital information packets so the conversation can be carried over the Internet. After this device is connected to your broadband router, your phone is connected to the box, and you have a phone service.

  You're probably used to hearing the terms cable modem and DSL modem. Because of their function in VOIP, they are often referred to as broadband routers. This is the hardware from which you receive your Internet connection, and therefore, your VOIP connection.

• IP telephone: Looks like a normal phone, but rather than plugging into a telephone jack in the wall, it's connected at an Ethernet port directly on your broadband router. The phone has the necessary software preinstalled to convert your conversations to packets of information that can be transported via the Internet.
• Soft phone: A soft phone is not really a phone at all. It's actually a software program that allows you to use your computer like a phone as long as you have a soundcard installed and a microphone headset attached. This seems like a pretty cumbersome way to have a phone conversation, but in some situations (such as if you're travelling with your laptop and have access to high-speed Internet access), a soft phone is a great tool to have access to.

One misconception is that to use Internet phone service, your computer must be turned on. In truth, the phone is connected to the Internet through your broadband router, and like the broadband router, it's always connected, whether the computer is turned on or not. Therefore, your computer doesn't have to be turned on for you to use your Internet phone service.