security analysis and improvement of an access control scheme for wireless body area networks

Wireless body area networks (wbans) have attracted a lot of attention in recent researches as they play a vital role in diagnosing, controlling and treating diseases. these networks can improve the quality of medical services by following the health status of people and providing online medical advice forthem, momentarily. despite the numerous advantages of these networks, they may cause irrecoverable problems for patients, if security considerations are not properly met. so, it is very important to find solutions for satisfying security requirements in these networks. a signcryption scheme can be consideredas one of the most important cryptographic tools for providing the security requirements in wbans. recently, kasyoka et al. proposed a signcryption scheme based on which they designed an access control protocol for wbans.they proved the security of their proposals in the random oracle model (rom).in this paper, we concentrate on kasyoka et al.’s proposals and show that their proposed signcryption scheme and consequently their proposed access control protocol for wbans are vulnerable against various attacks, in contrast to their claims. afterward, we fix the scheme to be secure against our proposed attacks.