# Tag Info

### Doing OTP two or more times with a biased TRNG: Will this have the same security as if was done with a non-biased TRNG?

Pretty much yes. Many TRNG designs are based entirely on digital circuitry, and do not involve any analogue components [see note]. It makes them simpler to incorporate on silicon. But unfortunately ...
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### Doing OTP two or more times with a biased TRNG: Will this have the same security as if was done with a non-biased TRNG?

The convergence of your suggested process towards unbiased bits is guided by the Piling Up Lemma. It will be slow. It is more efficient to use unbiasing procedures such as von Neumann unbiasing. See ...
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Accepted

### Doing OTP two or more times with a biased TRNG: Will this have the same security as if was done with a non-biased TRNG?

Better than using it once, but not as good as an unbiased TRNG. To see this, suppose our TRNG is very biased, producing a zero 10% of the time and an one 90% of the time. If we use the TRNG twice, for ...
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Given we have the sets $P$ and $C$, to find $k$, we need only find (one of) the pairs $(p,c)\in P \times C$ s.t. $p \oplus k = c$, as with this pair, $k$ is trivial to compute. First, we can note the ...