PSCPA: Patient Self-controllable Privacy-preserving Cooperative Authentication in Distributed m-Healthcare Systems

Distributed m-healthcare systems significantly facilitate efficient patient treatment of high quality, while bringing about the challenge of keeping both the confidentiality of the personal health information and the patients’ identity privacy simultaneously. It makes many existing data access control and anonymous authentication schemes inefficient in distributed mhealthcare systems. To solve the problem, in this paper, a novel authorized accessible privacy model (AAPM) is established. Patients can authorize physicians by setting an access tree supporting flexible threshold predicates. Then, based on it, a patient self-controllable privacy-preserving cooperative authentication scheme (PSCPA) realizing three levels of security and privacy requirement in distributed m-healthcare system is proposed. The directly authorized physicians can both decipher the personal health information and authenticate patients’ identities by satisfying the access tree with their attribute sets. Due to the indistinguishability of the transcript simulation from the patients and physicians for the indirectly authorized physicians, they can only decipher the personal health information rather than authenticate patients’ identities. The unauthorized persons can obtain neither. Moreover, PSCPA is extended in emergent cases and to resist Denial of Service (Dos) attacks. Finally, the formal security proof and simulation results show our scheme far outperforms the previous ones in terms of computational, communication and storage overhead. Keywords-Authentication; access control; privacy-preserving; security; distributed m-healthcare system