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Browsing without being tracked via Fingerprinting

Your browser aggrigates a *lot* of data about your computer, and it won’t hesitate to provide all of this data to a nosy web site. In fact, if a website requests a large dataset of your computer’s configuration, concatinates it together, and passes it through a hash function, the resulting hash can be farily unique.

This procedure can be done (and is done) on seperate websites to track users and their activity across multiple websites. If the same procedure [get data, concatenate, hash()] produces the same hash value when done on 2 seperate websites, the website can be fairly certain that you’re the same user. This technique for tracking users is known as Browser Fingerprinting.

Just to get an idea of how effective this is, here’s an excerpt from the above-linked article:

[The EFF] found that, over their study of around 1 million visits to their study website, 83.6% of the browsers seen had a unique fingerprint; among those with Flash or Java enabled, 94.2%. This does not include cookies!

You can test the uniqueness of your browser’s “fingerprint” using this handy EFF tool.

There is a really great document descirbing techniques that could be used to prevent yourself from being tracked using your browser’s “fingerprint” on the mozilla wiki here. Such techniques involve rounding your browser’s reported resolution to some multiple of pixles, which would (hopefully) decrase the uniqueness of your configuration.

Unfortunately, I couldn’t find any implementations of this awesome recommendation. If you know of one, please post of it in the comments!

In the meantime, I’ll just rely on noscript to help reduce my browser’s trackability.

Also, if you made it this far, you might want to checkout Duck Duck Go, a search engine which (unlike Google) does not track you.

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