Filtering Notes

• All filters over block and all filters under block.
• No two filters were created equal.
• Satisfaction with a filter is often based on educational philosophy and is not a good gauge unless viewed in that context.
• Filters and/or monitoring by themselves are NOT a solution.

Blocking

• Keyword filtering results in the most blocking of sites that should not be blocked because the word appears on the site.
• IP blocking results in the most blocking of sites that should not be blocked, because they share the same IP gateway as inappropriate sites
• Black lists often block based on political, social, or business agendas. This is becoming increasingly popular.
• Domain name blocking is the most efficient and desirable method, but is the least likely to be implemented, because it presents significant problems for the filtering company bottom line.
• Schemes that combine varying degrees of Keyword, IP blocking, and Domain name blocking that interact, provide the least disruptive type of filtering.
• Closed systems restrict access to everything but the resources within the system. They can range from low cost, locally created access lists to expensive learning environments.

Monitoring

• Packet sniffing provides a method of protecting students without blocking anything, but can have serious privacy issues attached.
• Room design and teacher monitoring is a non-technical strategy that could be implemented with the least objectionable technical strategy.
• Examination of log files can be time consuming. The efficiency depends on the expertise of the person examining the logs.

Rating Systems and Standards

• These can be browser based or dedicated software
• The relationship between systems and standards is often misunderstood.
• PICS is a standard with which web authors can indicate what kind of content is on their site.
• Third parties can create a system that uses the standards to set blocking criteria.
• Rating systems reflect the values of the groups that create the

Filter Logistics

• Client based may be a small-scale solution. Updating lists can be a problem. Expense must be examined. Easiest to circumvent.
• Server based is usually the most cost effective and requires the least amount of technical maintenance. Unblocking sites is a factor that must be looked at closely because of philosophy and time needed.
• Servers can be at the school, district, state, or ISP level. Each comes with its own set of considerations about time, cost, procedures and policies.