New DSL standard offers faster speeds

Although DSL speeds vary widely, the new G.SHDSL could be two to three times faster than most versions of DSL targeted at business customers. The G.SHDSL standard also can deliver data farther than earlier DSL technologies, which are limited to a relatively short distance.

Some European communications carriers are using the faster DSL (digital subscriber line) technology on a limited basis.

"The European market will see this. And the (U.S. local phone companies) are looking at deploying it to replace their business offerings now," said Pat Hurley, a DSL analyst at TeleChoice, a communications industry market research firm.

One of several versions of DSL high-speed Net access, the technology is being considered for use by some of the largest U.S. service providers, including SBC Communications, for its ability to serve a greater number of customers. Analysts believe some U.S. carriers may begin testing it next year.

A spokesman for SBC, the nation's largest DSL provider with more than 1 million customers, said the local-phone giant is considering several new DSL technologies.

"We are looking at a number of different flavors of DSL in our labs right now," said spokesman Fletcher Cook. "If (our customers) need more bandwidth, we're going to be there."

G-dot what?
G.SHDSL is short for the formal single-pair, high-bit-rate digital subscriber line, more casually known as symmetric high-speed digital subscriber line.

Approved by the International Telecommunication Union in February, G.SHDSL is a standard for a DSL technology capable of speeds of 2.3mbps (megabits per second), or up to 4.6mbps in some cases.

The data-transfer speeds are symmetric, meaning people can download and upload information at the same rate. Some versions of DSL technology offer faster downloads than uploads.

The new technology also can be delivered to customers farther than 18,000 feet, or about 3 miles, from the phone company switching facility by using repeaters--equipment that boosts the signal over distances. With other versions of DSL, this approximately 3-mile distance has limited the number of consumers and businesses capable of getting high-speed Net service in the past.

DSL signals typically degrade over distance, limiting the download speeds for some faraway customers.

Analysts and industry experts believe G.SHDSL will eventually replace today's DSL options, which primarily target either consumers or small businesses.

"It is being deployed in Europe today. They've just finished some of the trial phases," said Mark Peden, a member of the board of directors for the DSL Forum, a nonprofit organization to promote DSL. "What's going on in the U.S. is there are a number of lab trials with G.SHDSL. Competitive carriers have indicated that they plan to transition to it once it becomes available."

Despite the fast download speeds, most business DSL offerings today are unsatisfactory for all but the smallest business or home office. Few companies would attempt to host a Web site using today's business DSL technology, analysts say.

"Current SDSL is only good for low-end customers and small businesses," TeleChoice's Hurley said.

G.SHDSL is likely to be targeted at business customers when it is available in the United States, experts say.

DSL Forum's Peden expects to see some commercial availability as early as next quarter in Europe and early next year in the United States.

DSL is engaged in a battle with cable modems for broadband supremacy. Cable modems are primarily used by residential consumers, while DSL is used by both businesses and consumers. In the consumer market, cable leads in download speeds and customers, but G.SHDSL could help change that for the DSL sector.

DSL cousin not dead yet
But even though more speed will be available to DSL users, some within the industry think the current standard, ADSL, is far from extinction. ADSL, or asymmetric digital subscriber line technology, is widely used among residential consumers, which outnumber business customers.

"There will always be more lines of ADSL deployed than other DSL technologies," said Jay Fausch, a senior director of marketing at telecom equipment maker Alcatel, which makes both ADSL and S.HDSL equipment.

Fausch says ADSL can receive information at up to 8mbps but can only transmit at a rate of 0.8mbps.

This speed suits the home user, since the usual kinds of traffic sent from homes are e-mails and requests for Web pages, which consume relatively small amounts of bandwidth. The higher "downstream" speed also allows people to more easily receive larger incoming applications like streaming radio, MP3 files and graphics files.

Fausch believes that Web sites and storage centers, which send such bandwidth-heavy files, are more likely to migrate to the higher-speed technology, but that sheer numbers will still favor ADSL. "There are many more homes than there are businesses," he said.

Still, as Web surfers use larger applications like streaming video, DSL will have to adapt accordingly to compete with other Internet access technologies like cable, which pressures DSL equipment makers to improve receiving speeds.

"My personal view is that applications will test downstream limits more than upstream limits," Fausch said.