Multi-time server TRE method and system based on secret sharing and homomorphic encryption

The invention provides a multi-time server TRE method and system based on secret sharing and homomorphic encryption. The method comprises the steps that N time servers are set, each time server generates a Shamir secret sharing public and private key pair and a Paillier homomorphic encryption public and private key pair of the time server, generates a private key share group containing N private key shares, encrypts the private key share group and sends the private key share group to a time server management mechanism; the time server management mechanism calculates and publishes a system public key, calculates a private key share and sends the private key share to the time server; the receiver generates a private key of the receiver by using the attribute ID of the receiver; the sender specifies and publishes the decryption time T and the ciphertext C corresponding to the plaintext M, and sends the ciphertext C to the receiver; the time server calculates sub-time trap doors and periodically broadcasts the su