URL Filtering in IWSVA is a feature to filter Internet access that is based on the
               categories of URLs, such as "Adult", "Gambling," and "Financial Services." When a
               user requests a URL, IWSVA first looks up the category for that URL and then allows
               or denies access to the URL, displays warning, overrides password, or sets time quota
               based on the policies administrator has set up.
            For a specific URL category, there are six actions in IWSVA: "allow" to permit the
               access; "block" to stop the access; "block with override" to enter password to override
               the blocking, "monitor" to allow the access but log the action silently; "time limit"
               to set a time quota for selected URL categories, and "warn" alerts the user that there
               is a problem with the URL they are accessing. Block with Override mode might be used
               instead of just blocking or monitoring because:
            
               - 
                  
                  Some websites contain harmful code or the contents violate company policy. IT admins
                     must block access to these websites. But sometimes, useful information can be found
                     at these websites. Block with password override provides a mechanism that allows someone
                     to visit the blocked websites under the control of IT admin. This could improve company
                     efficiency. 
- 
                  
                  The "block with override" feature is used to temporarily allow an authorized person
                     to override the blocking rule for URL filtering. This feature is desired in many schools,
                     libraries, and commonly shared computer labs. For these types of environments, having
                     the ability to override a URL block by an approved user such as a teacher, librarian,
                     or supervisor is critical.