School web filtering needs extreme makeover

But perhaps the most prevalent concern among all panelists during the “Revisiting the Children’s Internet Protection Act: 10 Years Later” Google+ hangout—part of the American Library Association’s (ALA) Office for Information Technology Policy (OITP) and Office for Intellectual Freedom’s (OIF) larger project on CIPA and access to information—was school web filtering and its effects on 21st century student teaching and learning.

According to Deborah Stone, deputy director of the OIF, many of the lawsuits over the last 10 years involving schools and CIPA deal with issues in constitutional access to information.

Stone explained that though CIPA was originally created to protect children against sexually explicit images, schools and libraries usually have very limited control or discretion when it comes to school web filtering. In fact, most filtering is provided by vendors.

“The issue with CIPA is that it cannot suppress ideas, such as gay and lesbian information, access to Facebook, et cetera. Many times people think it’s the schools or libraries limiting access to these sites. But it’s the vendors, many of whom often have an agenda—for example, religious missions—that block access to information.”

Sarah Houghton-Jan, the information and web services manager for the San Mateo County Library, says many filters are only customizable if they are extremely expensive.

“The way filters work is by blocking IP addresses; keyword analysis–for example, ‘sexy videos’; link analysis; and pixel analysis for things like skin tone and body parts. But all filters differ based on how expensive and sophisticated they are,” she said.

But no matter how expensive or sophisticated the filter, Houghton-Jan says that even the best filter is only 83 percent effective for factors such as link analysis and IP addresses, and only 50 percent accurate for images or videos.

“The question then becomes: ‘Is it okay to use products that are inaccurate at least 20 percent of the time and more for images and videos?” asked Houghton-Jan.

She also argued that when vendors say that their product is 99 percent effective, it means they’re probably over-blocking content.

“When you over-block you’re essentially blocking constitutionally-protected content, which is where the ACLU lawsuits and other lawsuits occur. When you over-block that’s the same as being ineffective, knocking the product back down to about 80 percent effective.”

Outside of filter inaccuracy, she said that it’s “extremely easy” for students to get around filters.

“For example, most filters are English-centric, so if you type in something in another language the filter won’t pick it up,” she revealed. “Also, many times if a student uses a search engine other than Google the filter won’t work. Adult content sites are also starting to limit the number of links so as not to trigger filters; they’ll also misspell words and other tricks. Skin tone analysis is also inaccurate because all you’d have to do is make the image blue!”

(Next page: Solutions to vendor filtering)

Meris Stansbury

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