Homomorphic Symmetric Key Generation via Intermediary Mediation

The patent introduces a trusted third party (TTP) as an intermediary to generate and distribute symmetric keys to participating parties. This mediator approach allows the system to leverage homomorphic encryption's security benefits while avoiding the need for each party to independently manage complex homomorphic key pairs, thus reducing individual device complexity while maintaining overall system security.

The patent segments the key generation process into distinct phases: (1) TTP generates initial symmetric keys, (2) TTP distributes these keys to parties using homomorphic encryption, and (3) parties independently derive their own symmetric keys using the distributed encrypted data and local secrets. This segmentation allows distributed security to be achieved while reducing key generation complexity for individual parties, as they only need to perform local secret management rather than full homomorphic key generation.

The patent combines multiple secrets (party secrets and TTP secrets) into a single symmetric key through the homomorphic encryption process. The TTP encrypts the symmetric key using homomorphic encryption, allowing parties to contribute their secrets to the key derivation process while receiving only the final encrypted symmetric key. This merging approach achieves multi-factor protection without requiring separate communication channels for each secret, thus reducing communication overhead.