Based on the difficulty in computing discrete logarilhm and square 1001 onsome special conditions, we propose a basic threshold seeret sharing scheme for multiple secretswith multiple policies, which allows a group of...Based on the difficulty in computing discrete logarilhm and square 1001 onsome special conditions, we propose a basic threshold seeret sharing scheme for multiple secretswith multiple policies, which allows a group of users to share multiple secrttkeys and only onesecret shadow to be ktpt by each user. An efficient threshold decryption scheme with multiplepolicies is designed on the basis of the basic threshold scheme. This decryption scheme allowsmultiple secret keys to he shared among a groupof users, and each user to ketp only one secretshadow. Different public keys can be used to encrypt documents. If and only if the number ofcooperated users who koop the secret shadows is greater than or c-qual to the threshold value of thecorresponding secret key, they can cooperate to decrypt the documents. It is proved that theproposed scheme has very strong security, unless the attackers can solve the discrete logarithmproblem and the square root problem.展开更多
文摘Based on the difficulty in computing discrete logarilhm and square 1001 onsome special conditions, we propose a basic threshold seeret sharing scheme for multiple secretswith multiple policies, which allows a group of users to share multiple secrttkeys and only onesecret shadow to be ktpt by each user. An efficient threshold decryption scheme with multiplepolicies is designed on the basis of the basic threshold scheme. This decryption scheme allowsmultiple secret keys to he shared among a groupof users, and each user to ketp only one secretshadow. Different public keys can be used to encrypt documents. If and only if the number ofcooperated users who koop the secret shadows is greater than or c-qual to the threshold value of thecorresponding secret key, they can cooperate to decrypt the documents. It is proved that theproposed scheme has very strong security, unless the attackers can solve the discrete logarithmproblem and the square root problem.