Re: generating keys by using only part of longer random number

On Jun 10, 11:59 am, David Eather <eat...@xxxxxxxxxx> wrote:
Kristian Gjøsteen wrote:
Kim Schulz  <kimu...@xxxxxxxxx> wrote:
If I have a random number generator that e.g. generates 512bit long
keys but I only need 160bits of them. Would the quality of the
randomness then be compromised if I always just uses the first 160bits
of the key?

If the generator samples 512 bit strings from the uniform distribution
(or something that looks like the uniform distribution), then it is
ok. Otherwise, it depends on the exact distribution.

The OP might want to look for BBS stream generatorhttp://en.wikipedia.org/wiki/Blum_Blum_Shub
Which may be useful for the job

Thanks for the input guys! appreciate it. The BBS seems to be
something I can actually use for another project I have so thanks for
that input too.
.

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