HOWTO: Use DD-WRT To Bypass Filters – Part 1: The story

This is part 1 of 3 in a series. This series is actually for an English class assignment, but I decided to put it on my main blog instead of my second blog (http://antani02.blogspot.com/).
Use these methods at your own risk. If your workplace has an Acceptable Use Policy that forbids employees from bypassing the filter, then think before making the decision to do so.

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The first time I bypassed an internet filter, I used WEP key cracking. I used this because there were 2 wireless networks, a non-filtered network, and a filtered network. It took me a few months to get it working properly, and at the end of it I had a fully functional method of cracking a 28-digit WEP key in 3 minutes with my laptop. I am now in a place where that will not work, so I had to exploit something else in the system to bypass the internet filter.

In case you don’t know what I am talking about, an internet filter is a filter that blocks certain websites (games, etc.)
The internet filter only filters port 80, and all other outbound ports are open (Yes, this is a very large security hole!) I started out by using SSH port forwarding from the filtered area to my home PC, effectively bypassing the connection (see diagram below).



I used that for a while, but decided to use something else that wouldn’t cost $9.00 a month in electricity. I then installed DD-WRT on my Linksys WRT160N router, and used the ssh server on the router.

This worked well too, but when I tried to play Second Life from the filtered area, it didn’t work. I then researched alternatives, and found that DD-WRT also has a VPN server. I decided to use the VPN server instead to see if that worked. It worked great, and although I don’t play Second Life anymore, it still has the added advantage of being able to access computers and printers on my home network.

In my next post, I will explain how to use VPN to bypass the filter.