A new RSA public key encryption scheme with chaotic maps

Public key cryptography has received great attention in the field of information exchange through insecure channels. In this paper, we combine the Dependent-RSA (DRSA) and chaotic maps (CM) to get a new secure cryptosystem, which depends on both integer factorization and chaotic maps discrete logarithm (CMDL). Using this new system, the scammer has to go through two levels of reverse engineering, concurrently, so as to perform the recovery of original text from the cipher-text has been received. Thus, this new system is supposed to be more sophisticated and more secure than other systems. We prove that our new cryptosystem does not increase the overhead in performing the encryption process or the decryption process considering that it requires minimum operations in both. We show that this new cryptosystem is more efficient in terms of performance compared with other encryption systems, which makes it more suitable for nodes with limited computational ability

A Public Key Cryptosystem Based on Singular Cubic Curve

An efficient and semantically secure public key cryptosystem based on singular cubic curve is proposed in this paper. It is about two times faster than the cryptosystem of David at the same security label and more efficient than the Koyama scheme at high security level. Further, the partially known plaintext attack and the linearly related plaintext attacks are analyzed and concluded that those are not possible in the proposed scheme

An Efficient Variant of RSA Cryptosystem

An efficient variant of RSA cryptosystem was proposed by Cesar [2]. He called it Rprime RSA. The Rprime RSA is a combination of Mprime RSA [3] and Rebalanced RSA [9, 1]. Although the decryption speed of Rprime RSA is 27 times faster than the standard RSA and 8 times faster than the QC RSA [6] in theoretically, yet due to the large encryption exponent, the encryption process becomes slower than the standard RSA. In this paper we tried to improve the efficiency of encryption process with less compromising with the decryption speed

SEQUENTIAL ENCRYPTION FOR MULTIPLE CHUNKS OF DATA IN CLOUD ENVIRONMENT

Cloud computing is a next generation computer paradigm for IT firm. The vital service of cloud computing is cloud storage, that permits owner to move data from their native computing systems to the cloud. Storing our confidential data to a public cloud is a challenging issue in cloud computing because of unauthorized access to the data. The proposed algorithm splits data and encrypts it using two different algorithms to improve the security level of the confidential data than the various techniques of existing encryption algorithms. The data is first partitioned into multiple chunks and then efficient encryption algorithms such as RSA algorithm and Blowfish algorithm is used for data encryption. It further proposes an efficient data access using indexing technique to retrieve the confidential data from cloud. Finally, it needs to decrypt multiple chunks to get actual data from public cloud. The objectives of the proposed techniques are to store confidential data in public cloud and ensure more security than the existing techniques

New Public Key Authentication Frameworks with Lite Certification Authority

Two variants of CA-based public key authentication framework are proposed in this paper. The one is termed as public key cryptosystem without certificate management center (PKCwCMC) and the other is termed as proxy signature based authentication framework (PS-based AF). Moreover, we give an implementation of the former based on quadratic residue theory and an implementation of the latter from RSA. Both of the two variants can be looked as lite-CA based authentication frameworks since the workload and deployment of CAs in these systems are much lighter and easier than those of in the traditional CA-based PKC

Survey on Security Issues in Cloud Computing Environment

ABSTRACT: Cloud has introduced a new concept of provision of on-demand resource to services on internet. Cloud provides an attractive model while allowing the service providers to save cost. It allows users to free themselves of tasks of resource management i.e. most efficient use of resources. It also allows centralization of information and resources so that the users can access them from anywhere using the internet. Generally the resources used to provide services belong to a third party. As the users don't have to invest capital in such resources it decreases costs. Even though cloud model is lucrative, users have been hesitant in adopting it, the major reason being security concern regarding their private data. In this paper we discuss about various security concerns in cloud environment

Adversary-dependent Lossy Trapdoor Function from Hardness of Factoring Semi-smooth RSA Subgroup Moduli

Lossy trapdoor functions (LTDFs), proposed by Peikert and Waters (STOC\u2708), are known to have a number of applications in cryptography. They have been constructed based on various assumptions, which include the quadratic residuosity (QR) and decisional composite residuosity (DCR) assumptions, which are factoring-based {\it decision} assumptions. However, there is no known construction of an LTDF based on the factoring assumption or other factoring-related search assumptions. In this paper, we first define a notion of {\it adversary-dependent lossy trapdoor functions} (ad-LTDFs) that is a weaker variant of LTDFs. Then we construct an ad-LTDF based on the hardness of factorizing RSA moduli of a special form called semi-smooth RSA subgroup (SS) moduli proposed by Groth (TCC\u2705). Moreover, we show that ad-LTDFs can replace LTDFs in many applications. Especially, we obtain the first factoring-based deterministic encryption scheme that satisfies the security notion defined by Boldyreva et al. (CRYPTO\u2708) without relying on a decision assumption. Besides direct applications of ad-LTDFs, by a similar technique, we construct a chosen ciphertext secure public key encryption scheme whose ciphertext overhead is the shortest among existing schemes based on the factoring assumption w.r.t. SS moduli

素因数分解に基づく暗号における新たな手法

学位の種別: 課程博士審査委員会委員 : （主査）東京大学准教授 國廣 昇, 東京大学教授 山本 博資, 東京大学教授 津田 宏治, 東京大学講師 佐藤 一誠, 東京工業大学教授 田中 圭介University of Tokyo(東京大学

Chosen-Ciphertext Secure RSA-type Cryptosystems

This paper explains how to design fully secure RSA-type cryptosystems from schemes only secure against passive attacks, in the standard model. We rely on instance-independence assumptions, which, roughly speaking, conjecture that for certain problems, an interactive access to a solver for another problem does not help the challenger. Previously, instance-independence assumptions were used in a negative way, to prove that certain schemes proven in the random oracle model were not provable in the standard model. Our paradigm applies virtually to all (weakly secure) RSA-type encryption schemes for which public-key RSA exponent can be arbitrarily chosen. As an illustration, we present a chosen-ciphertext secure variant of the Naccache-Stern encryption scheme