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Re: why compression doesn't perfectly even out entropy
Perry writes:
> Furthermore, I suggest you look up the Venona intercept work
> and tell me again about how far an advesary will go with a
> tiny toehold.
The Venona breaks came because the NSA had a lot of encrypted traffic and
some pads were used more than once, which is hardly a tiny toehold. After
years of dragging intercepted messages through each other, something finally
popped out. Messages encrypted with pads that were only used once are still
unbroken, AFAIK, even though the pads were simply generated by clerks banging
on keyboards.
Still, a tiny toehold is all a good analyist needs to break a non-OTP
cryptosystem, which attempts to protect a lot of information with only a
little bit entropy.
andrew