Mohammad Sabzinejad Farash

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In 2012, Piao et al. proposed a polynomial-based key management for secure intra-group and inter-group communication. In this notes, we point out that there are some security weaknesses of Piao et al.'s intra-group key distribution scheme. One main problem is that their scheme cannot prevent a group member to obtain other members' secret keys shared with(More)
Key agreement protocols are essential for secure communications in open and distributed environments. Recently identity-based key agreement protocols have been increasingly researched because of the simplicity of a public key management. The basic idea behind an identity-based cryptosystem is that a public key is the identity (an arbitrary string) of a(More)
—Certificateless cryptosystems were proposed by Al-Riyami and Paterson in 2003 [1] to solve problems of public key cryptosystems based on PKI and based on identity. Up to now, various types of certificateless cryptographic primitives as encryption functions, signature schemes, key agreement protocols and etc, have been designed. But to the best of our(More)
In 2012, Xie proposed an authentication scheme based on Elliptic Curve Cryptography (ECC) for Session Initiation Protocol (SIP). However, this paper demonstrates that the Xie's scheme is vulnerable to impersonation attack by which an active adversary can easily forge the server's identity. Based on this attack, we also show that the Xie's scheme is also(More)
Recently, Chou et al. (J Supercomput 66(2): 973–988, 2013) proposed two identity-based key exchange protocols using elliptic curves for mobile environments. The first one is an two-party authentication key exchange protocol to establish a session key between a client and a remote server. The second one is an extended version for three-party setting to(More)