Glossary

Web Filtering

What is Web Filtering?

Web filtering is a technology stops users from viewing certain URLs or websites by preventing their browsers from loading pages from these sites. Web filters are made in different ways and deliver various solutions for individual, family, institutional or enterprise use.

In general, Web filters work in two distinct ways. They can block content as determined by quality of the site, by consulting known lists which document and categorize popular pages across all genres of content. Or, they can evaluate the content of the page live and block it accordingly. Many Web filter tools work off of a constantly updated URL database that shows which websites and domains are associated with hosting malware, phishing, viruses or other tools for harmful activities.

On the surface, web filtering is pretty simple, but like all things, as you start to learn more, everything becomes more complex. With close to a billion active websites on the internet, there’s is no way that every website can be included on a web filtering programs exclusion lists.

Web Filtering Customer Base

The three largest groups that use web filtering are:

  • Parents - who wish to prevent their children from accessing content they consider undesirable or inappropriate.
  • Businesses - that want to prevent employees from accessing websites that don't pertain to their jobs. Also, web filters serve as an effective assistance in stopping some malware infection.
  • Schools - Schools tend to use web filtering in a similar manner to businesses and parents, hoping to block offensive and distracting content, while also hoping to protect against malware infection.

Web Filtering Types

  • Blacklist & Whitelist Filters - When using blacklists, an administrator (which might be a parent) manually enters all websites that are deemed inappropriate into the program, and those sites are subsequently blocked. Whitelists are used in exactly the same way, only in reverse – i.e. URLs are manually entered onto a whitelist, and all other websites are then off-limits.
  • Keyword And Content Filters - This type of filtering is in many ways similar to black and whitelist filtering, though with a slightly broader scope. Keyword and content filters will filter out websites that contain specific keywords or predefined content (such as pornography, for example).

Filter Customizations

As well as the two main filters listed, customization options also exist:

  • Client-side Filtering
  • Server-side Filtering
  • Enterprise Filtering
  • Personal Filtering
  • Malware Control

Why Web Filtering is Important

For anyone concerned with using the internet safely, web filtering can be an excellent tool to help prevent attacks or loss of security. Monitoring and filtering what employees share helps actively enforce IT policies as well prevent data leakage. The security of a business is essential, so when any level of confidential information leaks, it will cause harm to the company. For organizations that offer internet access available to the public, like schools or libraries, recent legislation, CIPA (Child Internet Protection Act) has made it mandatory to implement a filtering solution or lose funding. Web filters are capable of preventing users from accessing sites that execute malicious code on the user’s computer. Even on a small level, web filtering allows companies to block web sites that don’t support an effective work day,as well as not fitting the requirements of their security policies.

Learn More About Web Filtering

Further Reading:

Wikipedia: Content-control Software

How Barracuda Can Help:

Barracuda Web Security Gateway is a comprehensive solution for web security and management, it unites award-winning spyware, malware, and virus protection with a powerful policy and reporting engine. Advanced features ensure that organizations adapt to emerging requirements like social-network regulation, remote filtering, and visibility into SSL-encrypted traffic.

Do you have more questions about Web Filtering? Contact us now.