Masa's Journal: Censorship at my workplace and how to bypass it (sort of)

The company I'm working for has an HTTP proxy with censoring. It's very annoying.

I have to give credit to that person who has come up with this idea of multiply checks (the proxy checks for single words, content and URLs). It's pain in the ass and ruins legitimate surfing efficiently.

There seems to be (at least) three stages of checks made to the pages:

First, the proxy checks if the URL is prohibited. If it is, then the banner telling that the page is "illegal" is loaded instead of the page. I cannot figure out any way to bypass this without outside help. When I have to reach this kind of a page, I have to create an SSH tunnel between the university and my work computer to get the page loaded.

Second, the proxy checks all contents of the requested page. If the page contains questionable words then the proxy will replace those words with "----" mark. If there seems to be too many of these words, the whole page is censored out and the banner telling about "prohibited words" is loaded.

Third, if the page seems to be clean but there is some special words at some place of the page then the rest of the page is censored out and the banner is placed there where the first occurrence of the "prohibited word" has been found.

The second and third cases are surprisingly easy to bypass. Just reload the page ten times and the proxy will allow the page to be loaded.

By the way, the proxy server in question is made by Symantec. And for my opinion, the server sucks. It can't handle moderate load efficiently, it just starts to generate "proxy errors". And under heavy load, the server crashes.