A Secure Data Self-Destructing Scheme in Cloud Computing

With the rapid development of versatile cloud services, it becomes increasingly susceptible to use cloud services to share data in a friend circle in the cloud computing environment. Since it is not feasible to implement full lifecycle privacy security, access control becomes a challenging task, especially when we share sensitive data on cloud servers. In order to tackle this problem, we propose a key-policy attribute-based encryption with time-specified attributes (KP-TSABE), a novel secure data self-destructing scheme in cloud computing. In the KP-TSABE scheme, every ciphertext is labeled with a time interval while private key is associated with a time instant. The ciphertext can only be decrypted if both the time instant is in the allowed time interval and the attributes associated with the ciphertext satisfy the key's access structure. The KP-TSABE is able to solve some important security problems by supporting user-defined authorization period and by providing fine-grained access control during the period. The sensitive data will be securely self-destructed after a user-specified expiration time. The KP-TSABE scheme is proved to be secure under the decision l-bilinear Diffie-Hellman inversion (l-Expanded BDHI) assumption. Comprehensive comparisons of the security properties indicate that the KP-TSABE scheme proposed by us satisfies the security requirements and is superior to other existing schemes.