[zapps-wg] Powers of Tau Attestation

[Sean Bowe]

There are potentially few useful entropy sources on an isolated system with
its peripherals removed that has just booted (for example), so a cat
walking across the keyboard can be used to strengthen the randomness at
little cost. It's mostly defense-in-depth.

Sean

On Mon, Jan 22, 2018 at 1:59 AM, Bastien Teinturier via zapps-wg <
zapps-wg at lists.z.cash.foundation> wrote:

> It's a good point, and I was wondering why this "manual input" entropy is
> needed.
> I don't understand what it adds to the entropy implicitly grabbed from the
> system by the executable.
> If we assume that an adversary is able to monitor the system and replicate
> the entropy of the random generator used in the code, that adversary is
> probably able to grab the input to the process as well right?
> I'm interested in learning more about why you felt it was necessary to ask
> the user to provide some random input.
>
> Cheers,
> Bastien
>
> On Sat, Jan 20, 2018 at 2:04 PM, Daira Hopwood via zapps-wg <
> zapps-wg at lists.z.cash.foundation> wrote:
>
>> On 18/01/18 13:46, Bastien Teinturier via zapps-wg wrote:
>> > Powers of Tau Attestation
>>
>> Notice that PowersOfTau_2.jpg leaks the additional entropy provided
>> to the computation. That's ok, it uses operating system entropy as
>> well; just noting that future participants might want to avoid that.
>>
>> --
>> Daira Hopwood  ⚧Ⓐ
>>
>>
>
>
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> Bastien Teinturier
>
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