Secure Data Access Control Scheme Using Type-Based Re-encryption in Cloud Environment

摘要

Cloud computing service provider cannot be totally trusted due to data security reasons, risk of data security and violation of privacy factors should be considered. Especially, guaranteeing data confidentiality is required. To solve these problems, S.C. Yu etc. proposed scheme which guarantees data confidentiality and fine-grained access control. However, data confidentiality can be violated by collusion attack of revoked user and cloud server. To solve this problem, we guaranteed data confidentiality by storing and dividing data file into header and body. In addition, the method of selective delegation regarding the whole or partial message according to delegator's reliability towards delegate using type-based re-encryption was specified.