Updating the Web Filter 73Updating the WebFilterSince content on the Internet is constantly changing, make sure youupdate the Web Site Filter used by the Firewall on a regular basis. Whenyou subscribe to the Web Site Filter, you can specify that it is updatedautomatically every week for one year.It is important to note that host names, and not IP addresses, are used forall Internet filtering functions two reasons: Many blocked sites operate server pools, where many machinesservice a single host name, making it impractical and difficult to addand maintain the numerical addresses of every server in the pool. Many sites included in the Web Site Filter regularly change the IPaddress of the server to try to bypass the Web Site Filters. This makesmaintaining a current list subscription critical for effective contentfiltering.Click Filter, and then select the Filter Update tab at the top of thewindow. A window similar to that in Figure 31 displays.Figure 31 Filter Update WindowChecking the WebFilter StatusThis section shows the status of the Web Site Filter and the date it waslast downloaded. If the Web Site Filter has not been downloaded theFirewall displays a warning message in red text.DUA1611-0AAA02.book Page 73 Thursday, August 2, 2001 4:01 PM
