Research On Digital Signature Scheme Based On Block Chain

An increasing number of contract signing work to be carried out through the network in light of the rapid development of information technology,and the signatories can exchange each other's digital signatures in the network to complete the electronic contract signing.Digital signature technology can guarantee the nonrepudiation of information.the technology,which plays the essential role in working of information security,can guarantee the non-repudiation of information.However,the existence of trusted center in the process of signing electronic contract has high security risk.How to design a more secure and fair digital signature scheme based on block chain and apply it to multi-party contract signing scenario becomes an urgent problem.Therefore,this paper uses the decentralization of block chain to design three digital signature schemes suitable for multi-party contract signing scenarios.The main contents of this paper are as follows:(1)In the case that the block chain can be applied to multi-party contract signing scenarios,a threshold group signature scheme is proposed.A trusted third party is composed of a decentralized block chain.The mutual cooperation between nodes will generate some node private keys,and the information for other nodes to verify will be recorded on the block chain in time and can not be changed.The scheme introduces the mechanism of node joining and exiting,and adopts the means of updating the private key of each block chain node regularly to ensure the forward security of the scheme.At the same time,the scheme satisfies both non-forgery and non-repudiation.(2)A verifiable aggregate signature scheme based on block chain is proposed.Each signatory generates its signature key pair and temporary key pair,and promises the temporary public key.The common signature of each signatory is encrypted by using the shared public key,and the verifiable signature of each signatory is constructed.The scheme is flexible and variable to cope with changes in members.At the same time,it ensures the correctness,security and efficiency of the scheme.(3)A block chain based aggregation signature scheme for multi-party contract signing scenarios is proposed.The scheme consists of two stages,the off-chain and on-chain stages of the block chain.The signing and verification of the contract is completed in the off-chain stage of the block chain,if and only if the aggregate signature passes the verification to enter the chain stage;in the chain stage,the signatories use the fair exchange protocol to calculate the shared private key.In addition,through a series of performance analysis,to ensure the privacy,security and fairness of the contract signatories.