Too much information? Make the most of today’s Internet filtering systems

By Lars Kongshem

Something was amiss. In the middle of leading a workshop at his school district last year, Art Wolinsky discovered that the professional development web site he had helped build was being blocked by the district's Internet filter.

Wolinsky, the school's technology-infusion consultant, was baffled. The well-regarded Online Internet Institute (OII) professional development web site that he worked on didn't contain any pornography or other objectionable material. But after doing some sleuthing, Wolinsky found several adult web sites among the customers of the company that provided OII's web hosting services. It was a case of guilt by association. The district's filtering software was blithely blocking all sites hosted by that service provider, regardless of whether the individual sites were objectionable or not.

"Unblocking my site in our district wasn't a problem, but getting it off the vendor's master block list took a long time," recalls Wolinsky, who works for the Southern Regional School District in Manahawkin, New Jersey. In effect, his web site had become invisible to educators in districts that were using the same brand of filtering software. The vendor eventually resolved the problem, but the experience left Wolinsky rattled. The lesson, he says, is that filters are far from perfect: "There's no magic bullet."

An Ongoing Debate
The debate over the effectiveness of Internet filters has been around since filters made their debut in the mid-1990s. Although filtering technology has improved since then, it's clear that Internet filters are still far from foolproof. Overblocking remains one of the top concerns.

Best Practices

Selected Vendors

In May, the National Research Council released a report titled Youth, Pornography, and the Internet, which noted wryly that filters "can be highly effective in reducing the exposure of minors to inappropriate content if the inability to access large amounts of appropriate material is acceptable." The same month, a three-judge federal court panel in Philadelphia struck down the portions of the Child Internet Protection Act (CIPA) that applied to libraries. The judges called filters "crude" and noted that "any technology protection measure mandated by CIPA will necessarily block access to a substantial amount of speech whose suppression serves no legitimate government interest."

But the judges' ruling does not alter CIPA's provisions for schools, which require that schools filter Internet access in order to be eligible for E-Rate funding. This past summer marked the passing of the CIPA compliance deadline, and it's clear that interest in Internet filters has soared. In a survey released in June by the National School Boards Foundation, 91 percent of technology decision-makers in school districts around the country reported taking some action on filtering in the past year.

Yet filters are hardly new to K-12 education. Some school districts began implementing Internet filters as early as 1996, typically in response to community concerns about inappropriate material on the web. Over the past three years, the market penetration of Internet filters has increased from 58.3 percent to 76.9 percent of U.S. schools, according to Quality Education Data's Internet Usage in Teaching 2002 report.

Making Filtering Work
"We're in our sixth year of filtering," says Duane Baker, chief technology officer for the Northwest Ohio Computer Association (NWOCA), a regional data center that provides Internet access to 37 school districts in Ohio. With more than 68,000 students downstream from his data center's N2H2 Internet filter, Baker knows the ins and outs of filtering as well as anyone. His strategy: Give instructional staff the flexibility they need to do their job.

"We've set up the network with separate zones for each building, so that filtering rules can be customized for each school," Baker says. "That way we can filter differently at the high school level than at the elementary level."

"The technology coordinators in each school can decide whether to use more filtering or less," he adds. "As an IT professional, I shouldn't be making these decisions for them."

Baker also provides the instructional staff with an override password, which gives teachers the option to bypass the filter on a single PC for a limited time. To ensure safety, the filter is re-activated automatically after a preset time period. A log keeps track of where students go, even when the filter has been temporarily disabled, Baker says.

Although the log does record which sites were accessed at what time and on which computer, it's hard to track who was using a computer at any given time. "Many schools have unauthenticated networks, because it's difficult to make students in earlier grades log in and out-it would take up all the instructional time," Baker says. "Even authenticated networks are not foolproof, because students often forget to log out."

One of the most effective ways to filter the web-and one of the easiest to manage-is to use a server-based solution. At NWOCA, the filtering software runs on a server that is also used to speed up Internet access by caching frequently-used web pages. Automatic filter updates help ensure that the filter stays reasonably current with the vast number of new web sites that appear every day.

In addition, the regional data center uses a network switch from Packeteer Inc. to block applications such as chat, instant messaging, and music file-sharing-activities that consume valuable network bandwidth and have few educational uses. To round out the filtering arsenal, Baker uses Marshal Software's MailMarshal e-mail content filter to prevent unwanted spam from entering the network.

Being able to deal quickly with miscategorized sites is an important part of an effective filtering strategy. In the schools served by NWOCA, teachers have the option of reporting incorrectly categorized sites to the regional data center, or directly to the vendor. "Once the problem is reported, the filter list is usually updated nationally within 24 hours," Baker says.

Surprisingly, the greatest number of incorrectly blocked sites are in the pornography category, Baker says. These sites move frequently, and filter vendors can't keep up with the changes. "Last week's porn site URL may be today's new education site," Baker says. "It's impossible to block them perfectly."

Common Sense Filtering
Filter vendors say they've made big strides in the effectiveness of their products, and that a small amount of overblocking is unavoidable. "There have been great advances over the past couple of years as we've moved away from key-word filtering," says Bob Kessinger, product marketing manager for SurfControl. The company's product now filters 4.2 million URLs in 40 different categories.

Regardless, instructional technology leaders are quick to point out that even good filters are no substitute for teacher training, student supervision, and Internet savvy.

For starters, make sure your district has a strong staff development plan in place to impart appropriate Internet teaching methods, says Jeff Johnson, district technology coordinator for the Greendale School District in Wisconsin. "Many teachers have a false sense of security that all 'bad' sites are somehow blocked and that they don't need to pay attention to what the kids are doing," he explains.

Equally important, many educators say, is the need to teach students the skills they need to use the filter that lies between their ears. "We generally do a poor job teaching students information literacy skills," Johnson says. "I urge the library media specialists to take charge when it comes to teaching kids to search for information intelligently and responsibly."

In the end, perhaps this analogy offered in the National Research Council report is the most apt: "Swimming pools can be dangerous for children. To protect them, one can install locks, put up fences, and deploy pool alarms. All of these measures are helpful, but by far the most important thing that one can do for one's children is to teach them to swim."

Lars Kongshem is senior editor of Scholastic Administr@tor.