SIGNCRYPTION ANALYZE

The aim of this paper is to provide an overview for the research that has been done so far in signcryption area. The paper also presents the extensions for the signcryption scheme and discusses the security in signcryption. The main contribution to this paper represents the implementation of the signcryption algorithm with the examples provided.ElGamal, elliptic curves, encryption, identity-based, proxy-signcryption, public key, ring-signcryption, RSA, signcryption

The Insecurity of Two Proxy Signcryption Schemes: Proxy Credential Forgery Attack and How to Prevent It

Securing different online e-business activities usually requires applying different cryptographic algorithms. The proxy signcryption algorithms are designed for applications such as online proxy auction or online proxy signatures on business contracts, which require a proxy agent to sign on confidential messages. This paper proposes a proxy credential forgery attack to two recent proxy signcryption schemes in the literature. Using the attack, a malicious proxy signer can create a fake proxy credential from his original credential to extend his signing power. Simple modifications to these two schemes are also provided in this paper to prevent the attack without adding too much computational complexity. In addition to the contribution of introducing a new type of attacks to signcryption schemes, the paper also points out that, while designing a secure proxy signcryption scheme, not only the unforgeability of proxy signatures is important, but also that of proxy credentials as well

ID-based Ring Signature and Proxy Ring Signature Schemes from Bilinear Pairings

In 2001, Rivest et al. firstly introduced the concept of ring signatures. A ring signature is a simplified group signature without any manager. It protects the anonymity of a signer. The first scheme proposed by Rivest et al. was based on RSA cryptosystem and certificate based public key setting. The first ring signature scheme based on DLP was proposed by Abe, Ohkubo, and Suzuki. Their scheme is also based on the general certificate-based public key setting too. In 2002, Zhang and Kim proposed a new ID-based ring signature scheme using pairings. Later Lin and Wu proposed a more efficient ID-based ring signature scheme. Both these schemes have some inconsistency in computational aspect. In this paper we propose a new ID-based ring signature scheme and a proxy ring signature scheme. Both the schemes are more efficient than existing one. These schemes also take care of the inconsistencies in above two schemes.Comment: Published with ePrint Archiv

A Unlinkable Delegation-based Authentication Protocol with Users’ Non-repudiation for Portable Communication Systems

[[abstract]]For portable communication systems, the delegation-based authentication protocol provides efficient subsequent login authentication, data confidentiality, user privacy protection, and non-repudiation. However, in all proposed protocols, the non-repudiation of mobile users is based on an unreasonable assumption that home location registers are always trusted. To weaken this assumption and enhance the nonrepudiation of mobile users, a new delegation-based authentication protocol is proposed. The new protocol also removes the exhaustive search problem of the subsequent login authentication to improve the subsequent login authentication performance. Moreover, the user unlinkability in the subsequent login authentication is also provided to enhance the user identity privacy protection.[[incitationindex]]EI[[incitationindex]]CEPS[[booktype]]紙

An efficient FIS and RSA based Signcryption Security Scheme

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