Re: Java encryption implementation

From: megagurka (megagurka_at_yahoo.com)
Date: 11/29/05 

Date: 29 Nov 2005 04:02:25 -0800

TC wrote:
> There are several aspects of "random numbers" that are important in
> cryptography. One of these is randomness. (If the generator produces
> highly non-random results, this could help an attacker to crack it.)
> But another one is /unpredictability/ - a completely different thing.

Incorrect. Randomness and unpredictability are equivalent.

> Say you generate a huge number of sequential integers. That sequence of
> integers is:
> - randomly distributed (no integer appares more commonly than any other
> one);

Your sequence is not "randomly distributed".

> So my generator, which I offered as an instructive joke, was only meant
> to illustrate that randomness is /not enough/, and having a long period
> is also /not enough/. The numbers must also be /unpreictable/ - a
> completely different thing.

Of course randomness is enough for a RNG.

/JN

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