Zhaohui Cheng

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In recent years, a large number of identity- based key agreement protocols from pairings have been proposed. Some of them are elegant and practical. However, the security of this type of protocol has been surprisingly hard to prove, even in the random oracle model. The main issue is that a simulator is not able to deal with reveal queries, because it(More)
Identity-based encryption (IBE) is a special asymmetric encryption method where a public encryption key can be an arbitrary identifier and the corresponding private decryption key is created by binding the identifier with a system’s master secret. In 2003 Sakai and Kasahara proposed a new IBE scheme, which has the potential to improve performance. However,(More)
Sakai et. al in 2000 produced a method of construction identity based public/private key pairs using pairings on elliptic curves. In 2001, using the same key construction as Sakai et. al., Boneh and Franklin presented the first efficient and provably secure identity-based encryption scheme. In 2003 Sakai and Kasahara proposed another method of constructing(More)
Since Bellare and Rogaway’s work in 1994, the indistinguishability-based security models of authenticated key agreement protocols in simple cases have been evolving for more than ten years. In this paper, we review and organize the models under a unified framework with some new extensions. By providing a new ability (the Coin query) to adversaries and(More)
McCullagh and Barreto presented an identity-based authenticated key agreement protocol in CT-RSA 2005. Their protocol was found to be vulnerable to a key-compromise impersonation attack. In order to recover the weakness, McCullagh and Barreto, and Xie proposed two variants of the protocol respectively. In each of these works, a security proof of the(More)
In most of the existing identity-based key agreement schemes, it is usually assumed that either the communicated parties know each other’s identifier before the protocol starts or their identifiers are transferred along with the protocol messages. However, these schemes are not suitable for use in many real-world applications aimed to achieve unilateral(More)
Retrospective cohort study. To evaluate efficacy and relevant problems of in situ reconstruction of extensor muscle insertion on the C2 spinous process combined with titanium miniplates internal fixation in expansive open-door cervical laminoplasty in order to improve surgical treatment effect. Expansive open-door cervical laminoplasty has been widely(More)
Since Joux published the first pairing-based one-round tripartite key agreement protocol [12], many authenticated protocols have been proposed. However most of them were soon broken or proved not to achieve some desirable security attributes. In this paper we present two protocol variants based on Shim [19] and Zhang et al.’s work [23]. As the formalized(More)