A general threshold encryption scheme based on new secret sharing measure

A dynamic secret sharing scheme on general access structure is proposed based on bilinear maps. Combining it with the identity-based cryptography, a general threshold encryption scheme is proposed. The threshold encryption scheme can realize the secure transmission of secret in insecure channel, compared with other secret sharing schemes. This scheme is without secret exchange, so the decryption group changes according to the message importance level and this scheme can meet demand of the multi-task system. The security analysis shows that the proposed schemes have higher security.