why we call it entropy - Openssl

This is a discussion on why we call it entropy - Openssl ; Von Neumann counseled Shannon to call it entropy because "no one really knows what entropy is". ;-) I wanted to say that it's inherently problematic to use things like the "randomness" in the interarrival time of events like interrupts, etc. ...

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Thread: why we call it entropy

  1. why we call it entropy


    Von Neumann counseled Shannon to call it entropy because "no one
    really knows what entropy is". ;-)

    I wanted to say that it's inherently problematic to use things like the
    "randomness" in the interarrival time of events like interrupts, etc.
    to "gather" "entropy" -- Ted has touched on this with his comment on
    solid state disk drives, etc.

    A bit stream may have 1 bit of entropy per bit of message (i.e. an
    entropy of 1), and therefore be incompressible -- perhaps what Schwartz
    thinks he means when he says "truly random" -- and be entirely predictable.

    We want nicely-distributed "random" numbers without apparent bias,
    with an apparent entropy of one, so that 10 bits of key material
    is really 10 bits of key; what makes such numbers cryptographically
    useful is that no amount of collected material enables us to
    predict bits anywhere else in the stream (past or future, if viewed
    temporally).

    I have given Herr Schwartz enough of my grossmutterlich Freundlichkeit
    for one day. Ppppt.

    - M





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  2. Re: why we call it entropy

    Michael Sierchio wrote:

    > A bit stream may have 1 bit of entropy per bit of message (i.e. an
    > entropy of 1), and therefore be incompressible -- perhaps what Schwartz
    > thinks he means when he says "truly random" -- and be entirely predictable.


    In case this isn't obvious, apply Von Neumann's corrector to the fractional
    component of the binary representation of a transcendental number.

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