Learn More
We put forward a new algebraic framework to generalize and analyze Diffie–Hellman like decisional assumptions which allows us to argue about security and applications by considering only algebraic properties. Our $$\mathcal {D}_{\ell ,k}\text{- }\textsf {MDDH}$$ D ℓ , k - MDDH Assumption states that it is hard to decide whether a vector in $$\mathbb(More)
An attribute-based signature with respect to a signing policy, chosen ad-hoc by the signer, convinces the verifier that the signer holds a subset of attributes satisfying that signing policy. Ideally, the verifier must obtain no other information about the identity of the signer or the attributes he holds. This primitive has many applications in real(More)
Groth-Sahai proofs are efficient non-interactive zero-knowledge proofs that have found widespread use in pairingbased cryptography. We propose efficiency improvements of Groth-Sahai proofs in the SXDH setting, which is the one that yields the most efficient non-interactive zero-knowledge proofs. – We replace some of the commitments with ElGamal encryptions,(More)
Lossy trapdoor functions, introduced by Peikert and Waters (STOC’08), have received a lot of attention in the last years, because of their wide range of applications in theoretical cryptography. The notion has been recently extended to the identity-based scenario by Bellare et al. (Eurocrypt’12). We provide one more step in this direction, by considering(More)
Quick Response (QR) codes, used to store machine readable information, have become very commonnowa days and have found many applications in different scenarios. One of such applications is electronic voting systems. Indeed, some electronic voting systems are starting to take advantage of these codes, e.g. to hold the ballots used to vote, or even as a proof(More)
  • 1