Security Now 408 – The State Of Surveillance

And then [Mark Klein] says: “While doing my job, I learned fiber optic cables from the secret room were tapping into the WorldNet circuits by splitting off a portion of the light signal.” And that’s why the program is called PRISM, Leo. What does a prism do?

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You want to get all the traffic coming in and out of Google. You get as close to Google as you can. You get on the router that is feeding Google, and you clone all of the data. And that’s exactly – and that’s why it’s called PRISM is that now, at this bandwidth level, they’re using fiber optic cables, so it splits the light. The power drops by 50% down each of the splits because the power of the light has been split, but that’s – there’s still plenty. And so it’s going to be received easily by the other end. And then it goes off to this secret room controlled by the NSA.

An incredibly interesting and well-presented explanation of PRISM, as interpreted by Steven Gibson. A must read (or listen to the podcast).