A non-interactive and dynamic multi-party FHE scheme based on FHEW
摘要
The rapid advancement of Fully Homomorphic Encryption (FHE) has enabled secure computation over encrypted data, with LWE-based schemes serving as a foundational pillar in this domain. While several leveled and fast bootstrapping FHE schemes such as BFV, BGV, CKKS, GSW, FHEW, and TFHE have emerged, extending these constructions to the multi-party setting introduces significant challenges. Existing multi-party FHE schemes based on leveled constructions typically require costly key relinearization and interactive key generation, which limit scalability and efficiency. In this work, we present a novel multi-party FHE scheme based on a modification of the FHEW scheme. Our construction eliminates the need for relinearization, significantly reducing computational overhead. It supports a non-interactive key generation process similar to Multi-Key FHE, removing the dependency on a trusted third party or multi-round protocols. Furthermore, the scheme is dynamic, allowing new parties to join the computation without restarting the setup phase. Security is ensured under the semi-malicious adversarial model. This construction advances the practical applicability of multi-party FHE by offering a more efficient, flexible, and scalable approach to secure computation.