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A Multipurpose Key Agreement Scheme in Ubiquitous Computing Environments

Due to the rapid advancement of cryptographic techniques, the smart card has recently become a popular device because it is capable of storing and computing essential information with such properties as tamper resistance. However, many service providers must satisfy the user’s desire to be able to access services anytime and anywhere with the smart card computing devices. Therefore, multipurpose smart cards have become very popular identification tokens. In 2011, Wang et al. proposed an authentication and key agreement scheme for smart card use. Even so, two drawbacks still exist; that is, (1) the security requirement of mutual authentication has not been satisfied and (2) the authentication scheme cannot be used for multipurpose smart cards. In this paper, we propose an efficient and secure multipurpose, authenticated, key agreement scheme in which the user is required to register only once and can be authenticated without any registration center. Furthermore, the proposed scheme can be used in ubiquitous environments because of its low computation and communication overhead.