Ring signcryption enables a user to send a message confidentially and authentically to a specific receiver in an anonymous way.One of the main reasons for the slow adoption of identity-based cryptography is the inhere...Ring signcryption enables a user to send a message confidentially and authentically to a specific receiver in an anonymous way.One of the main reasons for the slow adoption of identity-based cryptography is the inherent key escrow problem.In this paper a new certificateless ring signcryption scheme from pairings is presented.It is escrow free in that no KGC is able to decrypt ciphertexts itself.We then formally prove the security of the new scheme in the random oracle model IND-CCA2 and EUF-CMA.展开更多
We show that the Zhang-Yang-Zhu-Zhang identity-based authenticatable ring signcryption scheme is not secure against chosen plaintext attacks.Furthermore, we propose an improved scheme that remedies the weakness of the...We show that the Zhang-Yang-Zhu-Zhang identity-based authenticatable ring signcryption scheme is not secure against chosen plaintext attacks.Furthermore, we propose an improved scheme that remedies the weakness of the Zhang-Yang-Zhu-Zhang scheme.The improved scheme has shorter ciphertext size than the Zhang-Yang-Zhu-Zhang scheme.We then prove that the improved scheme satisfies confidentiality, unforgeability, anonymity and authenticatability.展开更多
基金supported by National Key Basic Research Program of China(973 program) under Grant No. 2011CB302903National Natural Science Foundation of China under Grant No.60873231,No.61073188+1 种基金China Postdoctoral Science Foundation under Grant No.20100471355Natural Science Foundation of Jiangsu Province under Grant No. BK2009426
文摘Ring signcryption enables a user to send a message confidentially and authentically to a specific receiver in an anonymous way.One of the main reasons for the slow adoption of identity-based cryptography is the inherent key escrow problem.In this paper a new certificateless ring signcryption scheme from pairings is presented.It is escrow free in that no KGC is able to decrypt ciphertexts itself.We then formally prove the security of the new scheme in the random oracle model IND-CCA2 and EUF-CMA.
基金the National Natural Science Foundation of China (No. 60673075)the National High Technology Research and Development Program (863) of China (No. 2006AA01Z428)the State Key Laboratoryof Information Security,and the Youth Science and Technology Foundation of UESTC
文摘We show that the Zhang-Yang-Zhu-Zhang identity-based authenticatable ring signcryption scheme is not secure against chosen plaintext attacks.Furthermore, we propose an improved scheme that remedies the weakness of the Zhang-Yang-Zhu-Zhang scheme.The improved scheme has shorter ciphertext size than the Zhang-Yang-Zhu-Zhang scheme.We then prove that the improved scheme satisfies confidentiality, unforgeability, anonymity and authenticatability.