tailieunhanh - Management of confidentiality of cryptosystems using linear codes a bird’s eye view

In this paper, we investigate the management of confidentiality in terms of security notions of McEliece cryptosystem, the first encryption scheme using linear codes, proposed on the basis of the hard problems in coding theory and its variants in the provably secure approach. The original McEliece is only a one way function. Therefore to obtain the higher notions of security, modifications on the original scheme are proposed. | International Journal of Computer Networks and Communications Security C , , JANUARY 2014, 7–14 Available online at: ISSN 2308-9830 N C S Management of Confidentiality of Cryptosystems Using Linear Codes- a Bird’s Eye View Preetha Mathew K1 and Dr Mathew Cherian2 1, 2 Associate Professor, Department of Computer Science and Engineering and Principal, Cochin University College of Engineering Kuttanad, Pulincunnu, Alappuzha, Kerala, India ABSTRACT In this paper, we investigate the management of confidentiality in terms of security notions of McEliece cryptosystem, the first encryption scheme using linear codes, proposed on the basis of the hard problems in coding theory and its variants in the provably secure approach. The original McEliece is only a one way function. Therefore to obtain the higher notions of security, modifications on the original scheme are proposed. Li et al. in IEEE transactions on information theory (1994), proved that the security of McEliece cryptosystem and Niederreiter cryptosystem, the dual of McEliece cryptosystem are equivalent. In this paper we show that it is not true. Dolev et al. in their paper published in STOC (1991), coined the notion of non malleability which formalizes an adversary’s ability to create a different cipher text yı for a plain text xı from the cipher text y which is an encryption of x. It is seen that the McEliece system is malleable and Niederreiter system is non malleable in view of the security notions existing in the provably secure scenario. Keywords: CCA-2 Security, CPA Security, McEliece Cryptosystem, Syndrome Decoding, Code Indistinguishability. 1 INTRODUCTION Confidentiality and authentication are major goals of cryptography. Confidentiality can be obtained using encryption and authentication is obtained by digital signature. One of the basis of the security of encryption is provable security. The security notions widely used in the provably secure approach for the encryption