Consesus Score

"Consensus Score" allows individuals to hold a score that represents how much others trust them, which can help establish a new trust system. This score is kept using zero-knowledge proofs, meaning that the score itself cannot be revealed to anyone other than the score holder. Validators can input an account address to verify how highly someone is rated, but the actual score is not displayed. Instead, Consensus Score displays how many stars someone has based on their level of trust according to others, achieved through the use of zero-knowledge proofs. Our project utilizes zero-knowledge proofs to enable score holders to prove they are trustworthy while maintaining privacy, and validators can use the blockchain to know that the score cannot be tampered with, allowing them to determine whether someone is trustworthy or not based on their score.

In our project, we mainly use Homomorphic Encryption and zkSNARK. In the Consensus Score, when sender A inputs a score M, it is encrypted with the public key of receiver B. The encrypted score E(m, pkB) is then processed with Homomorphic Encryption. The encrypted score is added to the original score E(n, pkB). E(m, pkB) + E(n, pkB) = E(x, pk) is the result of this calculation. Once the calculation is completed, we check whether the sender is registered in the whitelist. If they are registered, we record the calculation result on the blockchain. When the score owner visits their MyPage or a verifier verifies the score, proof generation and verification begin on Circom. Encrypted total score and encrypted number of evaluators are input to public input on Circom. Average score calculation is performed on Circom, and the output is the average score and the rate. Circom proves the correctness of the input by inputting the total score still encrypted, and also proves the correctness of the average score calculation and the execution.