Abstract
A telecare medicine information system (TMIS) for health-care delivery service requires information exchange among multiple IT systems, where different types of users with different access privileges are involved. In TMIS, users generally communicate via public channels. Hence, authentication is essential to provide access to the genuine users. However, access rights for the correct information and resources for different services to the genuine users can be provided with the help of efficient user access control mechanism. The existing user authentication protocols designed for THIS only provide authentication, but for this kind of application, it is required that the authorized users should also have unique access privilege to access specific data. This paper puts forwards a new fine grained access control with user authentication scheme for THIS. We present the formal security analysis using both the widely accepted real-or-random model and Burrows Abadi Needham logic. The proposed scheme supports user anonymity, forward secrecy, and efficient password change without contacting the remote server. In addition, the proposed scheme is comparable with respect to communication and computation costs as compared with other related schemes proposed in THIS. Moreover, better tradeoff among security and functionality features, and communication and computation costs makes the proposed scheme suitable and practical for telecare medicine environments as compared with other existing related schemes.