Research Of Secure Multiparty Computation Protocals

The problem of Secure Multiparty Computation was firstly introduced by A.C.Yao in the Yao's millionaires'problem in 1982 and has drawn many researchers and institutes'interests. Secure Multiparty Computation allows a set of parties to compute an agreed function of their private inputs in a secure way guaranteeing the correctness of the output as well as the privacy of the partie, even if an adversary may corrupt some parties. The problem of Secure Multiparty Computation is fundamental in cryptography and widely used in many fields.We present our researches in three ways as follows:1.Researching the digital signature and analyze the strengths and shortcomings of current Group Signatures.Based on the difficulty of resolving Discrete Logarithm, we propose an improved Group Signature scheme and analyse the efficiency of the scheme.2.In this paper, we make a detaily research on Fair Exchange Protocal and construct a new optimized Fair Exchange Protocal. The proposed protocal is analyzed.Then we propose an optimized Fair Exchange Protocal without leaking information and analyze it.3.We use evaluation codes coming from arbitary order domains for construction of ramp schemes with strong multiplication that allows the secret to be chosen in an extension field, whereas the sheares lie in a base fields. Then we discuss the use of two ramp schemes among those in multi-party computation. From them protocols can be constructed for atomic secure multiplication.