Security Enhanced Attribute Based Signcryption for Private Data Sharing in Cloud

摘要

The combination of signature and encryption techniques ensures data integrity and confidentiality in cloud. Researchers suggest the signcryption method to improve the efficiency during data signing, encrypting, verifying and decrypting procedures by integrating signature and encryption into a single function. However, the obscure use of keys and excessive cryptographical simplification reduce the system security levels. This paper proposes the identity and attribute based signcryption algorithm to enhance the security of storage and sharing of remote data. The proxy re-encryption and multi-attribute authority based signcryption techniques are used to achieve fault-tolerant attributes management and collusion-resistant system. In the Healthcare system, the attribute-based signature, encryption and signcryption methods are separately applied to scenarios of different data security levels in order to keep data access efficiency. Accordingly, the security properties and the access efficiencies of proposed algorithm are compared with known methods.