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| bio | website | conradoplg.cryptoland.net |
|---|---|---|
| location | ||
| age | ||
| visits | member for | 1 year, 7 months |
| seen | 9 hours ago | |
| stats | profile views | 14 |
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Jan 22 |
answered | Modulus for elliptic curve point multiplication |
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Oct 4 |
awarded | Yearling |
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Sep 27 |
comment |
why $e(g,g)^N=1$ in bilinear pairings holds? Yes, since $e(g^{a_1},g^{a_2})^N = e(g,g)^{N a_1 a_2} = (e(g,g)^N)^{a_1 a_2} = 1^{a_1 a_2} = 1$. |
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Sep 27 |
comment |
why $e(g,g)^N=1$ in bilinear pairings holds? No, if the order of $g$ is the composite $N$, then $g^q$ and $g^p$ will be different than $1$. The reason that $e(g,g)^N = 1$ holds is that $e(g,g)$ is the generator of $\mathbb{G}_T$ and has order $N$. |
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Sep 27 |
answered | why $e(g,g)^N=1$ in bilinear pairings holds? |
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Sep 4 |
awarded | Critic |
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May 4 |
comment |
Elliptic curves for ECDSA You can find $n$ by factoring the order of the curve, which you have found with e.g. Schoof's algorithm. Then $n$ will be the largest factor, and $h$ is the order divided by $n$. |
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May 3 |
answered | Elliptic curves for ECDSA |
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Apr 16 |
answered | Useful pairings for cryptography |
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Feb 17 |
answered | How does the MOV attack work? |
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Feb 10 |
comment |
Best choice of finite field for AES on a 4-bit microcontroller? @IlmariKaronen: I guess you're right. Thinking back, you can compute inverses in $GF(2^4)$ by simply trying all 15 possibilities. It seems that this issue warrants some research :) |
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Feb 9 |
comment |
Best choice of finite field for AES on a 4-bit microcontroller? Using composite field arithmetic allows you to compute an inverse by computing a single inverse in $GF(2^4)$. It seems to me that the code required to compute this would itself be greater than 256 bytes, killing any advantage over using a precomputed S-box. But it's hard to say without actually implementing it. |
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Feb 7 |
answered | Best choice of finite field for AES on a 4-bit microcontroller? |
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Feb 3 |
answered | Can one implement AES on 4-bit microcontroller? |
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Jan 26 |
accepted | Helper data authentication in PUFs |
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Jan 26 |
comment |
Helper data authentication in PUFs I guess my question wasn't clear enough, sorry for that! Suppose that the PUF is used by some device to derive a key that is used to encrypt and authenticate its hard drive, for example. There is no user interaction. If the device generates and stores a key to sign $P$, then an attacker can change both the key and $P$ (that is, assume that there is no secure storage) and the security would be compromised. If you assume there is a safe place to store the second key and $P$, then why use a PUF in the first place if you can generate a key and store it there? |
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Jan 24 |
comment |
Helper data authentication in PUFs Thanks for the clarification, but I still don't understand something: how can I protect it against modification? For that I would need a key, but I'm using the PUF to get a key in the first place. Is there any kind of guarantee that an attacker can't change $P$ in such a way to force the system to derive a key $R'$ of his choice? |
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Jan 24 |
comment |
Helper data authentication in PUFs I see, it makes sense if the PUF is used for authentication. But what if the PUF is used to generate a key for a device? |
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Jan 24 |
asked | Helper data authentication in PUFs |
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Jan 10 |
comment |
Would it be secure to use random numbers from random.org in a cryptographic solution? One application I can come up with is for validating randomness tests. But for the usual applications (e.g. generating keys), I don't see how random.org could be useful. |
