Defining DSL

DSL stands for Digital Subscriber Line. This is a high-speed Internet connection, usually measure in megabits per second, compared with the kilobytes per second of a dial-up modem. It's not usual for a DSL connection to be 50 times faster than dial-up.

How to Use It

You pay for DSL on a monthly basis, just like you would with a dial-up connection. Service comes with an external DSL modem that you plug into your computer (or into a router if you want to connect multiple computers) and an installation CD to set up your account.

DSL and Phone Service

DSL is usually bundled with standard phone line service, but you don't need to have a home phone. This latter option is called a "dry loop" or "dry line" and will usually be a little more expensive than getting DSL with a phone line.

DSL Availability

DSL can usually be ordered in several tiers of speed, but the highest speed may not be available in your area. This is determined by how close your location is to the central office where your line would get connected to the Internet by the provider.

Service Comparison

DSL is usually not as fast as cable Internet, but it has a reputation for higher sustained connection speeds. Although you used to have to log into a DSL account to connect, this information is now stored once on the modem itself, so you can just open up an Internet browser and surf.

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DSL overview