User's Manual

Security Services > Content Filter
704
SonicOS Enhanced 4.0 Administrator Guide
URL Cache
• Cache Size (KB) - Configure the size of the URL Cache in KB for the SonicWALL.
Tip Tip! A larger URL Cache size can provide noticeable improvements in Internet browsing
response times.
Configuring SonicWALL Blocking Features
Once you configure your settings in the N2H2 Properties window, you can configure
SonicWALL blocking features including Restrict Web Features, Trusted Domains, and
Message to Display when Blocking from the Security Services > Content Filtering page.
Restrict Web Features
Restrict Web Features enhances your network security by blocking potentially harmful Web
applications from entering your network. Select any of the following applications to block:
• ActiveX - ActiveX is a programming language that embeds scripts in Web pages. Malicious
programmers can use ActiveX to delete files or compromise security. Select the ActiveX
check box to block ActiveX controls.
• Java - Java is used to download and run small programs, called applets, on Web sites. It
is safer than ActiveX since it has built-in security mechanisms. Select the Java check box
to block Java applets from the network.
• Cookies - Cookies are used by Web servers to track Web usage and remember user
identity. Cookies can also compromise users' privacy by tracking Web activities. Select the
Cookies check box to disable Cookies.
• Web Proxy - When a proxy server is located on the WAN, LAN users can circumvent
content filtering by pointing their computer to the proxy server. Check this box to prevent
LAN users from accessing proxy servers on the WAN.
• Known Fraudulent Certificates - Digital certificates help verify that Web content and files
originated from an authorized party. Enabling this feature protects users on the LAN from
downloading malicious programs warranted by these fraudulent certificates. If digital
certificates are proven fraudulent, then the SonicWALL blocks the Web content and the
files that use these fraudulent certificates. Known fraudulent certificates blocked by
SonicWALL include two certificates issued on January 29 and 30, 2001 by VeriSign to an
impostor masquerading as a Microsoft employee.
Trusted Domains
Trusted Domains can be added in the Restrict Web Features section. If you trust content on
specific domains, you can select Don’t block Java/ActiveX/Cookies to Trusted Domains
and then add the Trusted Domains to the SonicWALL by clicking on Add. The Add Trusted
Domain Entry window appears for entering the trusted domain name.
Don’t Block Java/ActiveX/Cookies to Trusted Domains - Select this option if you have
trusted domains using Java, ActiveX, and Cookies. To add a trusted domain, enter the domain
name into the Add Trusted Domain field. Click OK to add the domain to the list of trusted
domains. To delete a domain, select it from the list, and then click Delete.