How to Compartment Secrets

Gaëlle Candel (1, 2) , Rémi Géraud-Stewart (2, 1) , David Naccache (2)

1 Ingenico Group S.A.
2 DI-ENS - Département d'informatique - ENS Paris

Secret sharing splits a secret s into $$\ell $$ shares in such a way that $$k\le \ell $$ shares suffice to reconstruct s. Let $$\rho _{i,j}$$ be the probability that shareholder i disclose their share to shareholder j, with $$0 \le i,j < n$$ .Given $$k \le \ell \le n$$ , to whom $$\ell $$ individuals should we hand shares, if we wish to minimize the probability that one of them reconstitutes s?

Domaines: Informatique [cs]

Gaëlle Candel, Rémi Géraud-Stewart, David Naccache. How to Compartment Secrets: Trust Everybody, but Cut the Cards. 13th IFIP International Conference on Information Security Theory and Practice (WISTP), Dec 2019, Paris, France. pp.3-11, ⟨10.1007/978-3-030-41702-4_1⟩. ⟨hal-03173906⟩