RC2PAS: Revocable Certificateless Conditional Privacy-Preserving Authentication Scheme in WBANs

Wireless body area networks (WBANs) are an essential part of health-care system. It collects the patient’s biomedical data through sensors and sends the data to the remote doctor. Based on these data, remote doctors can provide the patient with a detailed diagnosis and suitable treatment. However, in wireless communication environment, WBANs may be affected by various attacks, which leads to privacy leakage. Before WBANs come into application, data confidentiality and patient privacy are the main challenges for us. Therefore, we proposed a revocable certificateless authentication scheme that effectively overcomes these problems. In this scheme, to realize large-scale applications, we divided WBANs into several independent areas, and each area is responsible for the patients in its own area. Once a malicious user appears, revocation center can change the key of its own area to achieve efficient revocation. This approach disperses the management burden of the network manager and realizes conditional privacy-preserving. Besides, bilinear pairing is not used in this scheme, which greatly reduces the computational cost. It is especially important for clients with limited capabilities in WBANs. It is proved that the security of this scheme is equivalent to the assumption of elliptic curve discrete logarithm in a random oracle.