July Focus: The Need for Speed
By John Anderson

Connecting to the Internet has become as simple as turning on your television. Web pages now pop instantly onto your screen, and files download in scant seconds. In many places, the World Wide Wait is over. Even better, you can gain entry to this high-speed wonderland for not much more than you’re currently spending for dial-up access.

When you need more than dial-up speed, there are many ways to get there. The major choices currently are leased hardwired lines (rated from T1 (1.5megabits/second) to T3 (45 megabits/second)), cable wires, Digital Subscriber Lines (DSL), and wireless connections.

There are obviously several ways to connect to the Internet at high speeds, but the two most common for home use are through a cable TV modem, or through a DSL telephone connection. Each mode has advantages and disadvantages.

Cable modems use your existing cable TV connection, and allow you to connect to the Net at a potential rate of up to three million bps. Contrast this to the 28 or 56 thousand bps modem you’re probably currently using.

Cable modems rarely work at their maximum capacity because they share bandwidth with other modems on the same local node, which serves multiple users.

Cable is probably the largest current domestic type of broadband service. Cable modems were the only real game in town for a long time. The cable companies (like the telephone companies) already had their cables connected to homes everywhere, and those cables were capable of delivering Net connections at 1.5 mb/sec. All they had to do was add some new hardware.

Cable’s current popularity may be, in part, because the industry got together and agreed upon a standard of connecting the cable service and the modem at the customer site. It drove the cost of the modems down and made cable Internet among the cheapest broadband options out there, running in the $50 per month range across the U.S.

Be aware that cable may be a security problem if you are always connected to the network. Installing a firewall (software alone may be enough) is mandatory with cable connectivity if you have even slight privacy concerns.

Thanks to their high-capacity coaxial cabling, cable modem services offer a greater potential for speed than digital subscriber line. But in the real world, performance is only slightly faster than DSL.

That’s because while cable networks are theoretically capable of between 10 and 27 megabits per second, cable operators usually apply limits of between one and two megabits per second per user. And because bandwidth is shared, most users rarely achieve those limits. The more neighbors who log on, the lower the speed.

If several people in your neighborhood are online you’ll see performance decline. Still, the connection will be much faster than a 56K dialup connection.

To improve performance, cable operators are extending fiber-optic networks deeper into neighborhoods and creating more fiber nodes (the junction boxes that convert the higher-capacity fiber-optic signals to electrical signals running over coaxial cable). By reducing the number of houses being served by each node, bandwidth increases.

Lately, cable has probably been losing some market share lately to DSL. Though DSL only has about one million current subscribers, that number is on the rise.

DSL is based on a fixed connection to a similar modem at a phone company central office, so your bandwidth shouldn’t change even when your entire neighborhood decides to get online at the same time.

DSL offers fast speeds, not as fast as cable, but without the bandwidth sharing problem.

Cable installations are not usually present in most businesses. Cable - if it’s installed at all- is usually present in the home, whereas most offices would have only telephone lines in place.

You may see DSL called ADSL. The "A" stands for asynchronous, meaning that "downstream" speeds are much faster than "upstream" speeds. This makes sense-Web pages or files coming down to your computer are much larger than the typical tiny package of commands you send upstream when you click on a link. When comparing performance, downstream speed is the important factor.

Asymmetric DSL (ADSL) and Symmetric DSL (SDSL). ADSL is for home use, where downloading speed is paramount to the customer. One side (upload speed) is sacrificed for the other (download speed), hence the asymmetry in the name. SDSL is usually used in a business situation where uploads and downloads need to be of equivalent speed. SDSL requires the entire phone connection to operate, while ADSL allows a voice call to be placed whether or not someone is using the Internet connection.

WHICH ONE?

So, cable or DSL? Since both are relatively new technologies without a lot of overlapping coverage, your choice may be dictated more by what’s available in your area than by technological factors. At this point you can’t really go wrong selecting either. Your choice will probably come down to who your current cable provider is, what services are in your area and how their costs compare. Research each company and try to find out if they have had any substantial outages or loss of services in the recent past.

And, over the next few years as cable and telephone companies spend billions upgrading their systems, you can bet competition will dramatically expand your choices and lower your costs.

So don’t worry about it. If you feel the need for speed, and can get high-speed access in your location, go ahead and take the plunge.

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