Secure Secret Sharing Technology And Application

Secret Sharing is an important branch of Cryptography research,which has important applications in information storage,secure multi-party computation.It has become a basic tool of constructing secure protocols/schemes.This paper analyzes some basic secret sharing schemes.On the basis of those,we propose a more secure secret sharing scheme,also give some applications in the threshold cryptography.Firstly,we describe the problem of Publicly Verifiable Secret Sharing schemes,which are as follows:during the verifying process,only one party to be verified,the other is default to be honest.Based on it,we propose one Strong Publicly Verifiable Secret Sharing Scheme,which increases the verification process:Distribution-Check and Reconstruction-Check based on discrete logarithm problem.The conflict makers need to provide authentication information.The scheme can make it better to ensure the security of secret reconstruction.Secondly,we analysis the exiting common problems in secret sharing scheme:under some conditions it is not able to resist the attack from outsiders and insiders.To solve this problem,the paper firstly proposes a basic threshold secret sharing scheme based on Linear Code.When the number of participants is more than threshold value,according to the uncertainly principle of solving equations,the component information from participant is random,which can resist outsiders and effectively protect share.Meanwhile in case that outsiders achieve partial components information,the secret is impossible to recover.Second,on the basis of above scheme,we construct secure asynchronous secret sharing scheme based on linear combination and random parameters.The scheme can resist attack from insiders in asynchronous networks.Meanwhile,the share of participant can be reused.Finally,we propose the multi-level security threshold cryptosystem,compared to single-level security,which need more requirements in terms of security.It needs security policy to be achieved.This paper uses the combination of linear code threshold secret sharing scheme and Elgamal signature and decryption to design group signature and group decryption algorithms with multi-level security.Meanwhile,the schemes can resist attacks from outsides and insiders.