Research And Application Of Secure Multiparty Computation Protocols

This paper summarized the current research status of multiparty computation protocols, introduced the four types of multiparty computation protocols and analyzed them. The four types of multiparty computation protocols are: multiparty computation protocol based on OT (Oblivious Transfer), multiparty computation protocol based on VSS (Verifiable Secret Sharing), multiparty computation protocol based on threshold homomorphic encryption and multiparty computation protocol based on Mix-Match. On basis of the analysis of the strengths and shortcomings of the protocols, the paper improved on the four types of multiparty computation protocols. The improvements are as follows: (1) Multiparty computation protocol based on OT: Introduced access structure to this type of multiparty computation protocol, thus avoid the previous protocol's connatural disadvantages: The protocol can only realize the special ( n, n )-threshold access structure. With this access structure, even one malicious participant can stop the protocol. The improved protocol can realize any access structure. (2) Multiparty computation protocol based on VSS: 1) Introduced access structure to this type of multiparty computation protocol, which makes the improved protocol realize any access structure and avoid the previous protocol's connatural disadvantages: can only realize the special (t , n )-threshold access structure where n ≥2t ? 1. 2) Provided a new protocol of binary multiplication operation AtomMul . With the help of AtomMul , this type of protocol can overcome the tie of the original protocol's: n ≥2t ? 1. AtomMul provides the possibility of realizing any access structure. 3) Provided a protocol of unitary reversion operation, and thus the multiparty computation protocol can calculate any function defined on the fields of the protocol. (3) Multiparty computation protocol based on threshold homomorphic encryption: 1) Introduced access structure to this type of multiparty computation protocol, which makes the improved protocol realize any access structure and avoid the previous protocol's connatural disadvantages: can only realize the special (t , n )-threshold access structure where n ≥2t ? 1. 2) Provided a protocol of unitary reversion operation, and thus the multiparty computation protocol can calculate any function defined on the fields of the protocol. (4) Multiparty computation protocol based on Mix-Match: 1) Introduced access structure to this type of multiparty computation protocol, which makes the improved protocol realize any access structure and avoid the previous protocol's connatural disadvantages: can only realize the special (t , n )-threshold access structure. 2) Provided a protocol to validate the correctness of building a blind table, and so ensure the correctness of blind tables that are cores of this type of multiparty computation protocol. In the end, based on the analysis of the character of the existed protocols, this paper provided a new multiparty computation protocol. This outstanding character of this protocol is: It's easy to compute the multiplication and reversion operation while it's complex to calculate addition operation. Another strength of this protocol is that it has no limit on the number of inputs to an operation, it can realize d entities multiplication operation and addition operation.