[Cryptech Tech] Suggested changes to TRNG

[Basil Dolmatov]

How one can be sure that this is enough? 

Warmup delay is a possible solution to give system _some_ time to start, but should not be the only reason to consider entropy output as usable.

Tests should be performed to make sure that the output has good quality and can be used. 

dol@ с iPad

> 5 окт. 2015 г., в 16:40, Joachim Strömbergson <joachim at secworks.se> написал(а):
> 
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> Aloha!
> 
> Joachim Strömbergson wrote:
>> Russ Housley wrote:
>>> A pause seems prudent, but it is unclear to me how long it should 
>>> be.
> 
> Ok, I've implemented a warmup delay solution. Right now the entropy
> providers will not make any entropy available to the mixer before
> WARMUP_CYCLES. Currently this value is set to 1M cycles. With a 50 MHz
> clock we delay first mixing with 20 ms.
> 
> For the rosc based entropy providers this means that we will throw away
> close to 4000 bits that we otherwise would have collected and used.
> 
> - -- 
> Med vänlig hälsning, Yours
> 
> Joachim Strömbergson - Alltid i harmonisk svängning.
> ========================================================================
> Joachim Strömbergson          Secworks AB          joachim at secworks.se
> ========================================================================
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