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DIGITAL SUBSCRIBER LINE EXPLAINED
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DSL, or Digital Subscriber Line, promises an internet connection speed faster, smoother, and more reliable than dial-up.
By utilizing frequencies above the telephone bandwidth, DSL can encode more data to achieve higher data rates that would otherwise be possible in the restricted frequency range of a Plain Old Telephone System (POTS - a real descriptive term!) network. Intrinsic to the DSL network is the DSL modem (a more technically correct term is DSL Transciever, though DSL modem is more widely used among DSL customers). DSL modems use digital coding techniques to squeeze up to 99% more capacity out of a copper telephone line without interfering with regular phone services. DSL can allow simultaneous voice and high-speed data services such as super fast Internet access over a single pair of copper telephone wires. That means you can use the telephone for your telebabad while chatting over your favorite chatroom at the same time (can't get enough, huh)! The DSL service provider (ISP), on the other hand, has a DSL Access Multiplexer (DSLAM) to receive customer connections. A DSLAM takes connections from many customers and aggregates them onto a single, high-capacity connection to the Internet.
In addition, DSL is more convenient than dial-up because you don't have to wait for a connection or disconnect your phone to get online. You can talk on the phone and surf the Web at the same time with one phone line, so there's no need for the extra expense of an additional phone line for your computer.
There are two major types of DSL: Asymmetric DSL or ADSL, and Symmetric DSL or SDSL. The major difference is the upstream and downstream speed. In ADSL, the downstream speed is higher than the upstream speed (thus the name asymmetric), and are able to have speeds of up to 8 Mbps. It is ideal for heavy downloads. SDSL has mirror upstream and downstream speeds, which could reach 2 Mbps. Ideal for cost-cutting firms that require dependable and fast internet connection.
DSL has emerged as the most promising upgrade for the present dial-up connection that you may have at home or in your office. Compared to other means of upgrading connections like ISDN, dedicated line and Cable Modem, DSL is a more cost-effective means of upgrading the dial-up connection you have right now. Less expensive, less investment required on equipment, less drawbacks, yet will perfectly fit the job of providing faster, more stable internet access. That's the DSL promise.
(search www.google.com for more DSL information)
-10 September 2002 |
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