Detecting and protecting software
Put simply a Web filter is a product which filters or blocks access to objectionable material, and/or access to the Web. Objectionable material could include specific advertising, pornography, or known malicious websites. The filter can also be used to block access to specific, but not objectionable web content if required depending on the user’s requirements. As such Web filters are sometimes referred to as Content Filters.
The way in which network traffic is either blocked or filtered can be achieved by various methods. Ultimately there will be a hardware device or software program that includes a set policy of rules that have been compiled by the manufacturer, and/or the customer themselves. This list of rules will provide a yes/no answer to enabling access to any site or content listed in the policy list.
Any sites or content to be blocked are classified as being ‘Blacklisted’, whereas any specific sites or content that is accessible is classed as ‘Whitelisted’.
Web filtering is not infallible and whilst there have been massive leaps of advancement in this field, in some instances it can still be possible to access materials with the use of web-based proxy services on the web itself. As such it is usually recommended that web filtering is used in conjunction with other software products, such as in a UTM (Unified threat Management) firewall device.