We've known for years that color laser printers can embed a series of tiny yellow dots on pages they print. The dots — almost invisible under normal circumstances — can be used to determine which particular printer produced the image. Essentially, each printer outputs its own serial number. This is great for busting counterfeiters but raises all sorts of privacy concerns. Now, MIT students are getting involved in the campaign against the dots with the new Seeing Yellow project.
Imagine that every time you printed a document, it automatically included a secret code that could be used to identify the printer — and potentially, the person who used it. Sounds like something from an episode of "Alias," right?
Unfortunately, the scenario isn't fictional. In a purported effort to identify counterfeiters, the US government has succeeded in persuading some color laser printer manufacturers to encode each page with identifying information. That means that without your knowledge or consent, an act you assume is private could become public. A communication tool you're using in everyday life could become a tool for government surveillance. And what's worse, there are no laws to prevent abuse.
More at: http://www.shadowmonkey.net/articles/privacy/seei
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