Security and privacy protection in cloud computing: Discussions and challenges

A group key agreement protocol enables a group of communicating parties over an untrusted, open network to come up with a common secret key. It is designed to achieve secure group communication, which is an important research issue for mobile communication. In 2007, Tseng proposed a new group key agreement protocol to achieve secure group communication for a mobile environment. Its security is based on the decisional Diffie–Hellman assumption. It remedies the security weakness of the protocol of Nam et al. in which participants cannot confirm that their contributions were actually involved in the group key. Unfortunately, Tseng’s protocol is a nonauthenticated protocol that cannot ensure the validity of the transmitted messages. In this paper, the authors shall propose a new authenticated group key agreement to remedy it. It is based on bilinear pairings. We shall prove the security of the proposed protocol under the bilinear computational Diffie–Hellman assumption. It is also proven to a contributory group key agreement protocol.

A new authenticated group key agreement in a mobile environment

Analyzing the scientific evolution and impact of e-Participation research in JCR journals using science mapping

Certificate-based verifiably encrypted signatures from pairings

Multi-proxy signature is one of the useful primitives of the proxy signature. Till now, only a few schemes of identity-based multi-proxy signature IBMPS have been proposed using bilinear pairings, but most of the schemes are insecure or lack a formal security proof. Because of the important application of IBMPS scheme in distributed systems, grid computing, and so on, construction of an efficient and provable-secure IBMPS scheme is desired. In 2005, Li & Chen proposed an IBMPS scheme from bilinear pairings, but their paper lacks a formal model and proof of the security. Further, in 2009, Cao & Cao presented an IBMPS scheme with the first formal security model for it. Unfortunately, their scheme is not secure against the Xiong et al's attack. In this paper, first, we present an IBMPS scheme, then we formalize a security model for the IBMPS schemes and prove that the presented scheme is existential unforgeable against adaptive chosen message and identity attack in the random oracle model under the computational Diffie-Hellman assumption. Also, our scheme is not vulnerable for the Xiong et al's attack. The presented scheme is more efficient in the sense of computation and operation time than the existing IBMPS schemes. Copyright © 2013 John Wiley & Sons, Ltd.

Zuhua Shao

Papers

Improvement of identity-based proxy multi-signature scheme

Self-certified signature scheme from pairings

Cryptanalysis of Xia-You group signature scheme