Many readers have asked for advice on how to protect their kids from accidentally or purposefully viewing Internet porn, so over the next week or so Security Fix will examine various free methods for helping users block adult Web sites on their home networks.
One ingenious approach comes from OpenDNS. It offers a service to help filter out porn without installing software. Because the service works on a network level, it can easily be deployed across any operating system or network.
OpenDNS filters out Web page requests at the domain name system level. DNS is responsible for translating human-friendly Web site names like "example.com" into numeric, machine-readable Internet addresses. Anytime you send an e-mail or browse a Web site, your machine is sending a DNS look-up request to your Internet service provider to help route the traffic.
Most Internet users use their ISP's DNS servers for this task, either explicitly because the information was entered when signing up for service, or by default because the user hasn't specified any external DNS servers. By creating a free account at OpenDNS.com, changing the DNS settings on your machine, and registering your Internet address with OpenDNS, the company will block most porn sites from loading via any browser. Reboot, log back in to your account, and you should be all set.
You can change the DNS settings on each computer in your home. But if your network is behind a wireless router, a speedier and more reliable solution is to change the DNS settings on the router (see this link for instructions broken down by router model). That should cover all of the systems that connect to that router.
I tested the service using Internet Explorer 7 on a Windows Vista machine, but it shouldn't matter which browser or operating system you are using as long as you've correctly changed the DNS settings on that machine or on your router.
Answered by
Ashish Yadav
at
7:46 PM on July 07, 2008