IDG News Service — Nearly 650 million households will have broadband Internet service by 2013, but the growth rate of high-speed access will slow between now and then, research company Parks Associates predicted on Tuesday.

The number of broadband households worldwide should grow by 15 percent this year, and that growth rate will remain in double digits for the next couple of years, said Parks analyst Kurt Scherf. But by 2012, growth will slow to just 6 percent, Parks predicts.

Much of that expansion will be concentrated in less-developed parts of the world, especially the Asia-Pacific region, according to Scherf. China and India should be major drivers of growth, though there are still questions about how India's broadband build-out will progress, he said. This trend will make Asia-Pacific a much bigger part of the global broadband audience, rising from 40 percent of the world's broadband households last year to more than 49 percent -- roughly half -- by 2013, he said. Meanwhile, North America was home to 19 percent of the world's broadband users last year but will have just 15 percent by 2013.

In developed regions such as Europe and North America, so many people already use broadband that there is a shrinking population of potential new customers. Additions will slow most in Europe, according to Scherf. The U.S. government's stimulus package may buoy North American growth over the next two years, but it is still likely to fall from 8 percent this year to 6 percent in 2010, he said.

Growth in other areas, such as Latin America and Africa, is harder to predict, Scherf said. Wireless Internet access is likely to play a major role in less-developed regions where no wired infrastructure exists, he said. This may have powerful implications for makers of Internet client devices and software, because broadband users who skip straight to wireless may never buy a traditional desktop or laptop PC, Scherf noted.

Asia's growing share of the broadband market could shift the center of the network equipment market and even of innovation, Scherf believes. Vendors such as China's Huawei Technologies and ZTE will grow by building much of the infrastructure for China's planned broadband build-out, which will make them more competitive worldwide against Alcatel-Lucent, Nokia Siemens Networks and other Western manufacturers, he believes. Meanwhile, growing Asian demand may cause more broadband invention to emerge from that part of the world.

But broadband isn't standing still in developed markets, where service providers will be adding fewer new subscribers but more new services for existing customers. Those include IPTV (Internet Protocol television), connections to more consumer electronics devices, and services that bridge wired and wireless networks, Scherf said.