Content Management, Filtering and the World Wide Web

Article excerpt

Filtering is Not Censorship

The fact that pornography on the Internet is both ubiquitous and unavoidable and that students may access it -- from school, at home, from the library, with friends, etc. -- suggests only that we as parents, teachers and community members must be aware of the risks and consequences. Most importantly, we should understand the difference between censorship and filtering.

The Merriam-Webster Dictionary ( defines "censor" as "an official who examines materials for objectionable matter; an official (as in time of war) who reads and deletes material considered sensitive or harmful." Censorship is an act of government that, by definition, precludes free choice. The US constitution guarantees free speech, and thus restricts government censorship dramatically. Censorship at other times is a violation of our civil rights.

Parents and teachers filter students and kids' exposure to all sorts of things all the time. We monitor their playmates and don't let them talk to strangers. We are encouraged to monitor and control what shows they watch on TV, the songs they listen to on the radio and the books they read. This is to a very great degree what good parenting is all about.

Schools act in "loco parentis" when teaching children and so standards of health and safety that apply to parents apply generally to teachers. Just as importantly, teachers teach by providing students with information and accompanying analysis. The whole notion of a scope and sequence suggests that as teachers we take responsibility for determining the information content of a child's education. By teaching them arithmetic before we teach them calculus we filter their exposure to mathematical information.

Acceptable Use Policies

Many schools are adopting "Acceptable Use Policies" -- documents that describe how the Internet is to be used in school and the consequences for its misuse. To be most effective, acceptable use policies should be based on a thorough analysis of student needs for information and protection. Schools should post their policies on their Web sites, send them home to parents and teach them to students. Some schools require students to sign the Acceptable Use Policy, often before granting free Internet access. Schools should consider linking their Acceptable Use Policies to any filtering technology they employ. Fortunately, there are multiple technologies available to help monitor and enforce acceptable use policies, so policies can be enforced in a flexible way that accommodates the needs of different schools and different students.

Monitoring Web Usage

Standard browser and server technology can guide our students to appropriate content while helping us stay involved and aware of what they are doing. All browsers include a "history" file that lists the time and date of every Web site accessed. Web proxy servers also provide a history or audit of sites accessed for all of the machines served. Some proxy servers include powerful reporting tools as well. These tools are basic to school use of the Web. However, monitoring alone can only be reactive, identifying problems after they happen. For proactive control, additional content filtering technology is necessary.


Filtering Technologies fall into three general types -- list-based URL filtering, text filtering, and content recognition technology.

List-Based Filtering

URL filtering, the most commonly used technology, is a database of "unacceptable" Web sites and domains. These lists are frequently categorized by type of content. Categories include obscenity, sexual content, alternative lifestyles, illegal activity, drugs, violence, hate speech and crimes, sports and various forms of leisure.

List-based filtering has two weaknesses. First, it is costly. The lists must be updated frequently, and users must pay ongoing subscription fees. …