The number of digital subscriber line (DSL) customers worldwide grew at an unprecedented rate from July through September, providing signs of life for the broadband market, according to a survey from the DSL Forum.

More than five million people worldwide signed up for DSL service between July 1 and September 30, an increase of nearly 20 percent over the previous three-month period, according to the survey, which was released Tuesday.

The release of the July-September figures follows the release of statistics for the same period from the Australian Competition and Consumer Commission, revealing that DSL is poised to overtake cable as the nation's dominant broadband technology.

The worldwide percentage increase is the largest ever recorded by the DSL Forum, said the group's chairman, William V. Rodey. Rodey added that the findings are encouraging him to stick with the forum's target of 36 million DSL customers worldwide by year's end and 200 million DSL subscribers by 2005.

The survey found that there are now about 30 million DSL users globally. That figure doesn't include high-speed Web surfing done via cable modems, which in general cost about US$10 less a month in the United States than DSL service does. By most estimates, about 15 million cable modems are in the United States, twice as many as there are DSL connections, but there are only five million other cable modem connections anywhere else in the world.

"In the US, (cable modem providers) are beating the hell out of us," Rodey acknowledged. "But globally we're beating the hell out of them."

A representative for the National Cable and Telecommunications Association, one of the largest cable modem industry groups, did not immediately return a call seeking comment.

The growth in broadband, regardless of how it is delivered, is a phenomenon of particular interest to US lawmakers, who are now deciding how to spread high-speed Web access across the United States. Many legislators believe faster Web access can make people more productive at their jobs and help increase the gross domestic product, but they have logjammed over how to facilitate the proliferation of high-speed connections.

The DSL Forum survey offers more fodder for the ongoing debate, which will spill into the next session of Congress. Rodey points out that while the US market for DSL grew by 11 percent, it wasn't able to improve on its 17th-place ranking among countries with the highest percentage of DSL use. South Korea ranks highest in the world, with 27 percent of the country using DSL connections.

The survey also found that strong growth of the number of DSL subscribers in Germany, Norway and Croatia helped Europe, as a region, have the second highest DSL penetration in the world. The combination of the United States and Canada is now in third place. The world leader is the Asia-Pacific region, the survey found.

"If you show a politician some of these numbers, this should get them into action," Rodey said.

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