An Efficient Lightweight Authentication and Key Agreement Protocol for Patient Privacy

Tele-medical information system provides an efficient and convenient way to connect patients at home with medical personnel in clinical centers. In this system, service providers consider user authentication as a critical requirement. To address this crucial requirement, various types of validation and key agreement protocols have been employed. The main problem with the two-way authentication of patients and medical servers is not built with thorough and comprehensive analysis that makes the protocol design yet has flaws. This paper analyzes carefully all aspects of security requirements including the perfect forward secrecy in order to develop an efficient and robust lightweight authentication and key agreement protocol. The secureness of the proposed protocol undergoes an informal analysis, whose findings show that different security features are provided, including perfect forward secrecy and a resistance to DoS attacks. Furthermore, it is simulated and formally analyzed using Scyther tool. Simulation results indicate the protocol’s robustness, both in perfect forward security and against various attacks. In addition, the proposed protocol was compared with those of other related protocols in term of time complexity and communication cost. The time complexity of the proposed protocol only involves time of performing a hash function T_h, i.e.,: O(12T_h). Average time required for executing the authentication is 0.006 seconds; with number of bit exchange is 704, both values are the lowest among the other protocols. The results of the comparison point to a superior performance by the proposed protocol.