The Commerce Department released a first-of-its-kind federal survey of online access and found that Americans in lower-income and rural areas often have slower Internet connections than users in wealthier communities. The data also found that 5 to 10 percent of the nation does not have access to connections that are fast enough to download Web pages, photos and videos.
Compiled in an online map that is searchable by consumers - assuming they have a fast enough broadband connection - the survey seems to confirm that there is a digital divide, something experts had suspected but lacked the data to prove.
Extending access to high-speed Internet is one of President Obama's priorities. He has outlined an $18 billion plan to blanket 98 percent of the nation with high-speed mobile broadband connections over five years.
But some experts were disappointed with the study, which was based on advertised maximum speeds submitted by companies such as Verizon, Comcast and AT&T. The Commerce Department didn't test the speed data, and many experts complained that the survey lacks pricing information, which would enable better comparisons of service across regions.
"Price is one of the most important variables to have," said S. Derek Turner, policy director of the public interest group Free Press. "And real speeds are important because it shows whether companies are really giving people what they are paying for."
Still, industry watchers praised the map - which will cost $200 million over five years, funded by the federal economic stimulus program - for shedding light on business practices that have long been murky. Companies closely hold information about where they operate, but the map discloses which kinds of services are available - cable, fiber, DSL and wireless - down to the census block level. It will be updated every six months.
"The national broadband map shows there are still too many people and community institutions lacking the level of broadband service needed to fully participate in the Internet economy," said Lawrence E. Strickling, assistant secretary of commerce for communications and information.
Researchers said the map will be an important tool for understanding which populations have access to high-speed Internet. "If you are an urban developer or are trying to do policy or subsidize users in an area for broadband, you were really doing that without a lot of detailed information," said Shane Greenstein, a professor at the Kellogg School of Management at Northwestern University.
The telecom and cable industries say that they are working to provide high speeds across the country but that the effort takes time.
Speed matters, experts say, because consumers with better Internet connections can be more productive and get more out of the Web. Generally speaking, a user needs a data speed of at least 5 megabits per second to smoothly watch a streaming YouTube video.
President Obama has said that networks with at least 10 megabit-per-second download speeds are key to competing economically with countries that have cutting-edge Internet services, such as South Korea and Germany.
The Commerce Department's telecom policy arm, the National Telecommunications & Information Administration, said 32 percent of U.S. households don't use the Internet at home, a slight decrease from last year.
Forty percent of rural homes don't connect to the Web, compared with 30 percent of urban homes, the agency said. Those who aren't using the Internet say they don't think it is a necessity and that prices are too high, and about 9 percent of people in rural areas say they don't have access to high-speed connections, according to the NTIA.
Often, the poorer areas of the country aren't being offered the fastest download speeds, according to the data.
In the District of Columbia, where about 18 percent of the population is considered poor, only 12 percent of homes can get broadband speeds as high as 25 megabits per second, the study found.
In neighboring Montgomery County, where 5.3 percent of residents live in poverty, the study showed that 98 percent have access to 25 megabit-per-second speeds, which make it easy to engage in video conferencing, streaming downloads and multiplayer video games. In Virginia's wealthy Fairfax and Arlington counties, 99 percent of residents have access to those speeds.
There are exceptions. One in five homes in the city of Baltimore is under the poverty line, but 99 percent of residents get access to speeds of at least 25 megabits per second.
Some industry officials said the government study underrepresents the actual spread of broadband services. For instance, the government reported that 82 percent of homes have access to broadband Internet from cable providers. But the trade association National Cable & Telecommunications Association says cable companies serve 93 percent of homes. About 15 percent of the country gets access to fiber broadband networks.
"We are confident that the cable broadband availability figures we cite are an accurate reflection of the consumer experience and fully expect that the national broadband map will become more accurate as the data collection process continues," said spokesman Brian Dietz.