Applying time-constraint access control of personal health record in cloud computing

Due to the advances in medical technology, popularity of education, and increase of public self-consciousness. The World Health Organization (WHO) has promoted the use of e-health tools. The digitalization of patients' personal health records enables doctors to review parients' complete medical records and enhance medical efficiency. A personal health record system is established in the cloud to achieve these above goals.Therefore, the aim of this study is to construct an authority management mechanism by incorporating bilinear pairing and time-constraint. The proposed scheme will ensure that an authorized medical personnel can obtain an decryption key only in the legal time interval.