162 CHAPTER 10: U SING CONTENT F ILTERING Using a browser on a client machine whose IP address is not blockedby Web Client Blocking to access the Web Interface.All client machines that you specify in the Cache Bypass screen will not beprevented by the Webcache from accessing the Web. Cache Bypass takesprecedence over Web Client Blocking when the Webcache receives aclient machine request. For further information, see “Cache Bypass” onpage 186.Using Web ClientBlocking with DHCPServersDynamic Host Configuration Protocol (DHCP) servers can be used withWeb Client Blocking in two ways: You can configure your network into subnets and assign specific clientmachines IP addresses within these subnets. You can then allow ordeny specific subnet IP address ranges access to the Web through theWebcache using Web Client Blocking.ExampleYou configure your user group A to use a subnet defined as10.1.2.0-255, and user group B to use another subnet defined as10.1.3.0-255. If you want to prevent everyone except group B fromaccessing the Web, you would set the Web Client Blocking to Deny allexcept and add the subnet 10.1.3.0-255 to the Web Client Blockinglist. Group B would then be able to access the Web, while everyoneelse, including group A, would have no access to the Web. You can configure your DHCP server to return specific IP addressesbased on the requesting client machine’s MAC address. You canconfigure Web Client Blocking to block or allow specific clientmachine IP addresses, or ranges of IP addresses, as appropriate.Setting Up WebClient BlockingTo set up Web Client Blocking using the Web interface:1 Log in to the Web interface.2 Click Content Filter on the Toolbar.3 Select Webcache Filtering > Web Client Blocking > Setup Client Blockingin the Navigation Tree.4 Check Enable Web Client Blocking.5 Select either: Deny all except — to stop all clients accessing the Web except forthose you specifically allow.dua1611-5aaa04.book Page 162 Friday, November 29, 2002 8:56 PM
