Questions tagged [threshold-cryptography]

Threshold cryptography is the art of chopping a secret into little bits, so that the secret can only be learned by possessing more than a threshold number of those bits.

Threshold cryptography is the art of chopping a secret into little bits, so that the secret can only be learned by possessing more than a threshold number of those bits.

This is useful, for example, if you want to share a secret with a group of people (who each will receive/carry a part of the secret) and you want to make sure that no single individual can learn the secret unless two or more people combine their secret parts (depending on how many the threshold defines) to learn the secret. Practically, this can be found in military (and other) realms, where launch codes tend to be protected by threshold cryptography – so that no individual can initiate a launch, but when a launch-controller and his superior both enter their secret keys, that creates a combined and valid authorization code.

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Is there any threshold-crypto library that is production-ready?

I am wondering if there is any available threshold crypto library that is well-audited and ready to be used in production. Any pointer is appreciated.
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Which groups are secure for DL-Problem?

I was wondering why some groups provide more security to cryptosystems relying on DL-Problem.
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Finding a key given partial keys

I'm working through an exam paper for a cryptography exam and I've come across a question I'm unsure on. Six users have been given the partial keys below $P(x) = (k + \sum_{i=1}^2 c_ix^i)\bmod{503}$ User X Y 1 10 25 2 20 405 3 30 272 4 40…
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Question about Threshold signature scheme "GG18"

I recently read the article on the threshold signature scheme “Fast Multiparty Threshold ECDSA with Fast Trustless Setup” and I have a question. In the key generation section, each player $P_i$ selects $u_i$ and then performs a $(t, n)$ Feldman-VSS…
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Does threshold crypto (m-of-n) guarantee that m peers discover the plain text?

In a threshold cryptosystem, is there any guarantee that all $m$ peers participating in retrieving a plain-text will all retrieve it? If not, is it possible to provide such a guarantee? For instance if the $m$ peers are hostile to each other, is…
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order of Lagrange interpolation in reconstruction of secret key

Does the order of Lagrange interpolation have any role in reconstructing the secret key in Shamir's secret share?