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Researchers Calculate Capacity of a Steganographic Channel

KentuckyFC writes "Steganography is the art of hiding a message in such a way that only the sender and receiver realize it is there. (By contrast, cryptography disguises the content of a message but makes no attempt to hide it.) The central problem for steganographers is how much data can be hidden without being detected. But the complexity of this problem has meant it has been largely ignored. Now two computer scientists (one working for Google) have made a major theoretical breakthrough by tackling the problem in the same way that the electrical engineer Claude Shannon calculated the capacity of an ordinary communications channel in the 1940s. In Shannon's theory, a transmission is considered successful if the decoder properly determines which message the encoder has sent. In the stego-channel, a transmission is successful if the decoder properly determines the sent message without anybody else detecting its presence (abstract). Studying a stego-channel in this way leads to some counter-intuitive results: for example, in certain circumstances, doubling the number of algorithms looking for hidden data can increase the capacity of the steganographic channel"

1 of 114 comments (clear)

  1. Re:Stenography FTW by zindorsky · · Score: 4, Informative

    I've always had a warm spot for stenography

    ...

    But how did we communicate our plans and schemes to actually be present at "hotspots" when the shit really went down? Stenography.

    ...

    Of course it's possible to break that kind of thing, but the point of stenography

    So you hid your messages with stenography? The action of process of writing in shorthand or taking dictation? This word you keep using ... I do not think it means what you think it means.

    --
    If the geiger counter does not click, the coffee, she is not thick.