Linux Security Through Proxy Servers

The internet can be a scary place, even for the most conservative of web users. One of the most critical protective urges is to keep your IP address anonymous, whether because you're reporting on human rights from within China or because you're just another user who doesn't like the idea of their identity being known to everyone in the forum. With Linux systems, there are a variety of powerful tools that can be used to make your computer that much safer—including the use of proxy servers.

There are many types of proxy servers, not all of which are useful for security purposes. Content filtering web proxies, for instance, can be used by web administrators to deny access to certain web sites, and hostile proxies can even be used to eavesdrop on other people's web use. Some proxy servers may even be used to cache web info to accelerate web surfing. To keep your computer secure, typically you'll be using some type of anonymizing proxy.

Essentially, an anonymizing proxy server is a server that acts as an intermediary between your computer and another server—in effect preventing all the random servers you normally connect to while surfing the internet from seeing your computer. The more layers of proxy servers between you and the rest of the internet, the safer you'll be—a technique sometimes called “daisy chaining”.

It should be noted that the use of anonymizing proxy servers may not be perfectly secure. There are malicious proxy servers out there which actually record everything you send through them, including passwords and logins, to disastrous effect. Because of the anonymizing powers of proxy servers, many trollers and spammers use them which in turn leads to many forums banning the IP addresses of known proxy servers - more an inconvenience than anything.

The Tor Project is a free software for users of any operating system to take advantage of “onion routing”, a technique that essentially swathes your computer in layers of proxy servers to hide it from other servers. If you're a Firefox user, there's even a Tor add-on that you can install to streamline the process considerably.

Tor has some major disadvantages, however. Because Tor uses so many different proxies, even compared to other proxy server security methods surfing the internet can become a painfully slow process. While there are methods to speed up it up somewhat, they are very intensive to install and tend to be very trying on RAM. Tor is also vulnerable to very specific types of computer monitoring, such as looking at the timing of the requests between the different proxy servers.

For those looking for less user-intensive security, Firefox and its massive user database of add-ons has rendered a significant number related to quick and easy handling of proxy servers. In addition to the aforementioned Tor add-on, there are also many free, open-source add-ons. The most complete of these is FoxyProxy , which offers the most features that can help you anonymize your surfing with ease. Proxy Toolbar lets you manually set your http proxies, while Environment Proxy lets you quickly modify environment variables more specific to Linux machines.

Other web browsers offer similar, though not quite as vast, options. The KDE-based web browser Konqueror offers limited proxy management, for example.

Other web browsers offer similar, though not quite as vast, options. The KDE-based web browser Konqueror offers limited proxy management, for example. Google Chrome for Linux by itself is also limited with regards to its proxy management, although as with Firefox there are suitable addons such as Proxy Switchy! Google Chrome for Linux is rapidly growing, so keep an eye out for more changes with regards to proxy management.

Just as with any proxy server, using any of these will slow your internet surfing down considerably—in general, the more proxy servers, the more secure, but the slower the use. Find the balance is between the two that suits you best!

Just as with any proxy server, using any of these will slow your internet surfing down considerably—in general, the more proxy servers, the more secure, but the slower the use. Whether that's worth the cost of security or not is up to you.

Maybe you're a little more hardcore than that and want to set up your proxy servers manually. What you're probably going to want to do is set up a SOCKS proxy server. Creating and configuring it for yourself is a very intensive process, but it can be worth it to have set it up yourself and not depend on 3^rd person applications. Here is an excellent guide to manually setting up firewalls and proxy servers on Linux systems.