Efficient Multi-Party Private Set Intersection with Better Security

We introduce Zero-share-Xor Garbled Bloom Filter and an efficient PSI protocol using oblivious pseudorandom function (OPRF). Our approach enhances security based on Chase et al. (Crypto'20). By minimizing heavy cryptographic primitives and relying mainly on symmetric-key encryption with necessary base OTs, our protocols achieve superior performance. It is secure against semi-honest adversaries and support collusion among clients (with at least two honest clients). Our experiments evaluation, utilizing multithreading to simulate protocol steps, demonstrates optimal concurrency under star-like and path-like communication graphs. Comparisons with state-of-the-art symmetric protocols show our MPSI protocols outperforming others in scalability and performance across varying numbers of parties and set sizes.