P3ASC: Privacy-Preserving Pseudonym and Attribute-Based Signcryption Scheme for Cloud-Based Mobile Healthcare System

With the development of wireless body sensor network and mobile cloud computing, cloud-based mobile healthcare, which extends the operation of healthcare provider into a pervasive environment for better health delivery and monitoring, has attracted considerable interest recently. However, how to keep data security and privacy in cloud-based mobile healthcare system is an important and challenging issue since personal health information is quite sensitive. In this paper, we introduce a new cryptographic primitive named privacy-preserving pseudonym and attribute-based signcryption (P3ASC) scheme, which can fulfill the functionality of pseudonym-based signature and key-policy attribute-based encryption in a logical step. We propose a provable secure P3ASC scheme from bilinear pairings and present a novel secure and efficient cloud-based mobile healthcare system by exploiting our proposed P3ASC scheme. The proposed system can ensure data confidentiality, integrity, source authentication and non-repudiation, but also can provide fine-grained access control and user anonymity.