We design cryptographic protocols that recognize best case (optimistic) situations and exploit them. As a case study, we present a new concurrent zeroknowledge protocol that is exp...
A zero-knowledge protocol allows a prover to convince a verifier of the correctness of a statement without disclosing any other information to the verifier. It is a basic tool a...
Abstract. We present a lower bound on the number of rounds required by Concurrent Zero-Knowledge proofs for languages in NP. It is shown that in the context of Concurrent Zero-Know...
Halpern, Moses and Tuttle presented a definition of interactive proofs using a notion they called practical knowledge, but left open the question of finding an epistemic formula...
We show that every language in NP has a (black-box) concurrent zero-knowledge proof system using ˜O(log n) rounds of interaction. The number of rounds in our protocol is optimal,...