Fog-Based Single Sign-On Authentication Protocol for Electronic Healthcare Applications

Increasing use of electronic healthcare (eHealth) services demands efficient and secure solutions. Such solutions need to ensure the prevention of unauthorized access to the patient data and provide faster response. Fog computing is a viable solution to provide faster responses in eHealth systems. Key distribution and authentication play a major role in providing security to patient data. Existing centralized architectures are susceptible to single-point-of-compromise, that is, the entire system is vulnerable when the centralized authority keys are unexpectedly revealed to an adversary. In this article, we present a fog-based semi-centralized architecture for key distribution and authentication, in which the key distribution service is delegated to individual fog servers. Thus, the fog servers become responsible for key distribution to the users without the involvement of the centralized authority, which forms a paradigm of multiple client–server architecture. Thus, achieving centralized trust by designing a single sign-on authentication in such environments is a challenging problem. We design a single sign-on authentication protocol for semi-centralized architectures to achieve centralized trust by ensuring that the user keys are independent of the centralized authority’s keys. A rigorous security analysis under the random oracle model is performed to prove that the proposed protocol is secure against single-point-of-compromise. We also conduct extensive experiments to show the practical perspectives of the proposed scheme. The results show that the protocol is suitable for eHealth applications, including emergency services.