【摘要】 为改善基于LWE的全同态密码方案不能被投入实际应用的窘境,对其效率问题进行研究,提出一种高效实用且具有全同态属性的密码方案。采用层次型结构,其内层使用椭圆曲线离散对数问题(ECDLP)保证其安全性,外层使用无噪音GSW保证其密文的全同态属性。将该密码方案应用于不可信云计算平台中单用户隐私数据的加密及存储后可知,该密码方案可行,运行效率满足用户对全同态操作反应时间的要求。更多还原

【Abstract】 To change the current dilemma of LWE-based fully homomorphic encryption schemes that it can not be put into the practical applications,its efficiency issues were studied,and a cryptographic scheme with the fully homomorphic property was proposed.A hierarchical structure was adopted,elliptic curve discrete logarithm problem was used in inner-layer to ensure security,and noiseless fully homomorphic encryption scheme was used in outer-layer to ensure the fully homomorphic property of the ciphertext generated using the proposed cryptographic scheme.By applying the proposed cryptographic scheme to encrypt and store the privacy data of the single-user in the untrusted cloud computing platform,this scheme is feasible and its operating efficiency meets user’s requirement of the operation response time.更多还原