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,...
In the bare public-key model (BPK in short), each verifier is assumed to have deposited a public key in a file that is accessible by all users at all times. In this model, intro...
Giovanni Di Crescenzo, Giuseppe Persiano, Ivan Vis...
The number of communication rounds is a classic complexity measure for protocols; reducing round complexity is a major goal in protocol design. However, when the communication time...
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...
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...