A Protocol for Checking Equality of Data Using Hash in Ideal Model of Secure Multiparty Computation

The ideal Secure Multiparty Computation (SMC) model deploys a Trusted Third Party (TTP) which assists in secure function evaluation. The participating joint parties give input to the TTP which provide the results to the participating parties. The equality check problem in multiple party cases can be solved by simple architecture and a simple algorithm. In our proposed protocol Equality Hash Checkin ideal model, we use a secure hash function. All the parties interested to check equality of their data supply hash of their data to the TTP which then compared all hash values for equality. It declares the result to the parties.

Classical cryptographic protocols in a quantum world

Cryptographic protocols, such as protocols for secure function evaluation (SFE), have played a crucial role in the development of modern cryptography. The extensive theory of these protocols, however, deals almost exclusively with classical attackers. If we accept that quantum information processing is the most realistic model of physically feasible computation, then we must ask: What classical protocols remain secure against quantum attackers? Our main contribution is showing the existence of classical two-party protocols for the secure evaluation of any polynomial-time function under reasonable computational assumptions (for example, it suffices that the learning with errors problem be hard for quantum polynomial time). Our result shows that the basic two-party feasibility picture from classical cryptography remains unchanged in a quantum world.