78 CHAPTER 7: CONTROLLING AND MONITORING WEB ACCESS
■ You can configure your network into subnets and assign specific client
machine MAC addresses to be provided IP addresses within specific
subnets by DHCP. You can then prevent specific subnet IP address
ranges from accessing the Web through the Webcache through Web
Client Blocking.
For example, you configure your user group A to use a subnet defined
as 10.1.2.0-255, and group B to use another subnet defined as
10.1.3.0-255. If you want to prevent group B from accessing the Web,
you would add the subnet 10.1.3.0-255 to the Web Client Blocking
configuration. Group B would then be unable to access the Web,
while group A would have access.
■ You can configure your DHCP server to return specific IP addresses
based on the requesting client machine’s MAC address. You can
configure Web Client Blocking to block either specific client machine
IP addresses, or ranges of IP addresses, as appropriate.
Configuring Web
Client Blocking
To configure Web Client Blocking using the Web interface:
1 Log in to the Web interface.
2 Click Device View on the Toolbar.
3 Select System -> Caching -> Client Machine Blocking in the
Navigation Tree.
4 Check Block Access From All Web Clients to enable Web Client Blocking.
5 In the Except these IP Addresses field, type the IP addresses or IP address
ranges of the client machines that you want to allow access and click
Add.
Example
You can enter
216.115.105.2-217.115.105.2 to allow access for that IP
address range, or enter
216.115.105.2 to allow access for that IP
address. Separate individual ranges or addresses with a comma.
CAUTION: If the browser on the client machine that you are using to
configure the Webcache is also using the Webcache as a proxy, and you
enable Web Client Blocking, you must ensure that you add the client
machine to the Except these IP Addresses field. If you do not do this,
access from the client machine to the Webcache will be blocked,
