Secure Data Collaborative Computing Scheme Based on Blockchain
Table 1
Specific steps of the calculation protocol.
MPC protocol
Input: for , there is an -dimensional matrix and a corresponding -dimensional vector , where
Initialization: randomly select a pair of public and private keys , decompose the private key to obtain subkey , distribute the subkey to each participant , and randomly select a reversible matrix with the same dimension for participant
Step:
1 Use public key to encrypt the matrix and corresponding vector owned by participant to obtain and ; then send and to
2 uses the public key to encrypt the matrix and the vector to obtain and ; calculate the encryption matrix and the phase encryption vectors at the same time
3 Use the invertible matrix to calculate and ; then send them to the corresponding participant
4 When the number of participants possessing subkey reaches the threshold, the master key is reconstructed by Lagrange interpolation formula, and the encryption matrix and vectors are computed by
5 Participant collaboratively calculates the linear equation to obtain
