Archive for the ‘Content Filtering’ Category

Filtering Pornography Sites with Free Tools

June 8, 2008 Leave a comment

How to filtering pornography sites with no cost ?. Use these tools to implement your objective:

Check and learn those tools from their sites. I have been try in my networks and the result is satisfied me. Although the free database (from BigURLBlackList) just contain hundred thousand of urls/domains (comparing with the commercial database that have million of urls from Websense or ISS for example). But it is enough for our network…

You can use the Dansguard Linux Server as a gateway to your ISP like the diagram below:

Dansguardian Linux Server as a gateway to the ISP

Or you can use your default router as a gateway for all of yours workstation and use PBR (Policy Based Routing) or WCCP (Web Cache Communication Protocol) to forward every HTTP traffic to Dansguardian Server. For this purpose, you must enable the transparent proxy option in Squid, and use Redirect option in the IPTables. All of those application running in one server. You don’t need to set the proxy server address on every workstion browsers, just use the existing default gateway.


One of disadvantage for use these implementiation is your networks public IP Address is just one, that is your Dansguardian IP Address, because Squid and IPTables is NAT-ing your workstation IP Address. One solution to prevent NAT-ing process (so your workstation can still use it local IP) is use TProxy option in IPTables. But for this purpose, you must recompile your Linux Kernel and your IPTables application to support TProxy.

Use the links below to learn furthermore: