What Is DSL?
DSL is a form of Internet service. DSL stands for Digital Subscriber Line. DSL is a “high-speed Internet service” whose main competition is cable Internet. DSL is a popular choice for online access because it is many times faster than simple dialup but doesn’t require a cable television service like cable Internet.
How Does DSL Work?
Unlike cable Internet, DSL runs on a standard copper telephone line, just like the dial-up service most of us had in the early days of the Internet. The difference is that DSL offers an exponentially faster Web connection than dial-up. DSL also transmits and receives data from the Internet without blocking the phone line. That means you can use your existing telephone connection to access the Internet without blocking phone service.
DSL service runs on the functionality of a DSL modem–this devices connects the telephone line in your wall to your computer. A DSL modem is what is known as a “modulator”–basically, a translator that turns your computer’s digital signals into voltage that travels across your standard telephone line to something called a Digital Subscriber Line Access Multiplier. Thankfully, this is simply known as DSLAM or “dee-slam.”
Your DSLAM is a giant switchboard for various DSL customers. The DSLAM handles all the different requests from the computers in your area connected to DSL, acting as a go-between from your home to the web of computers known as the Internet.
More DSL Details
The reason DSL and regular telephone service can take place at the same time is that the DSL service and your telephone signal exist on separate frequencies. If you imagine DSL and phone service as two different lanes on the same highway, it is easier to picture. Regular voice signals are sent on a low band (the slow lane) while Internet functions occupy a band that is many times higher than voice (the fast lane). This is also why you usually have to install a “filter” on your phone line if you want to use that line for DSL as well. This filter keeps the lower voice band free from signals bleeding in from the Internet band. This filter is not a requirement, but not using it could lessen your enjoyment of your phone and Internet service.
What Is ADSL?
Standard DSL, like the kind found in most homes, is actually called ADSL for “asynchronous DSL.” The word “asynchronous” is just a fancy way of saying that two things aren’t alike–in this case, your DSL signal is split up into two different forms, one stream for downloads and one stream for uploads. These two streams are different from each other in speed–most people’s download speed is much faster than their upload speed.
That’s because most of the time, we use the Internet in a “download” format–each time you click a link, you’re actually “downloading” information from the Internet. Upload requests are “smaller” than download requests, so your DSL service’s “upload” speed is many times slower. Since the download speed is much faster than the upload speed, the service is called “asynchronous.”
What Is SDSL?
Take the “a” off “asynchronous” and you get “synchronous DSL”, or SDSL. Any Internet subscriber that requires the ability to send large numbers of files or large amounts of data need faster upload speeds. In SDSL, the uploading and downloading streams are equally fast. SDSL connections are available in residential settings, though they may only be necessary for people that operate large websites or transfer large files. SDSL is much more expensive than standard ADSL.
What Is Naked DSL?
Since many people have long since given up their “land lines”, DSL service would normally require those people to open new phone lines. Since many people prefer to use their cell phone rather than a phone hooked up to a phone jack in their home, a DSL product that doesn’t require standard phone service was needed. “Naked DSL” provides DSL service without a need for telephone service. Naked DSL looks and acts just like ADSL but it doesn’t need residential phone service to operate.
Different DSL plans exist offering different speeds. Slower DSL connections cost less than plans that offer high speeds. Low-end DSL connections run as little as $12 per month, and even though it costs about the same, it is many times faster than dial-up Internet.
The average DSL plan runs closer to $20 a month. Top-tier ADSL connections only cost a little more, averaging $35 per month. What determines your DSL speed? The main factor in the speed of your DSL connection is the distance between your computer and the DSLAM that your signals are routed through. Obviously, the closer you are to the DSLAM, the better your signal will be.
DSL and Wireless Internet
Your DSL modem is usually “leased” to you for the duration of your DSL contract. You should consider purchasing your own modem and wireless setup rather than leasing the one your company provides, as the leased modem will be pretty low quality and won’t have router or wireless capability. If you want to use your connection wirelessly or network your computers, you’ll have to pay for a more expensive modem anyway. Before you have your DSL service installed, consider buying your own modem and wireless router setup rather than leasing the one offered by your DSL service provider.