Plaintext-aware encryption

About: Plaintext-aware encryption is a research topic. Over the lifetime, 1980 publications have been published within this topic receiving 101775 citations. The topic is also known as: Plaintext awareness.

Spatial Encryption under Simpler Assumption

Abstract: Spatial encryption was first proposed by Boneh and Hamburg. They showed that many useful encryption systems can be derived from it. In this paper, we describe two variants of spatial encryption. First we present a scheme that can be proved to be secure under the decisional bilinear Diffie-Hellman assumption, which is much simpler than the BDHE assumption used by Boneh and Hamburg. However, as a compromise, our ciphertext size and private key size are larger. We also discuss some techniques to shrink the private key of this scheme in a real application. Finally, we provide a hybrid construction which allows an optimal tradeoff between efficiency and security.

A novel substitution box for encryption based on Lorenz equations

Abstract: Complexity of an encryption algorithm is highly dependent on nonlinear components that drive actual security. Only nonlinear component in all traditional encryption algorithms is mainly Substitution Box (S-Box). In block ciphers, the relationship between plaintext amd ciphertext is abstruse via confusion operation. Due to the high sensitivity of initial conditions, utilization of chaotic equations in S-Box designing can extensively improve the security and strength of confusion operation. This paper present a novel 8 χ 8 S-Box based on the chaotic properties of Lorenz equation. In order to overcome the transient effects, initial values obtained via Lorenz equation is discarded in the proposed solution. To check the appropriateness of the proposed S-Box in image encryption scenarios, resultant encrypted image pixels from a traditional scheme are further substituted via the proposed S-Box. Standard performances indexes such as correlation coefficient, homogeneity, energy and contrast analyses have been carried out. All experimental results prove that the proposed S-Box essentially improved the security of a traditional image encryption scheme.

NICE - New Ideal Coset Encryption

Abstract: Recently, a novel public-key cryptosystem constructed on number fields is presented. The prominent theoretical property of the public-key cryptosystem is a quadratic decryption bit complexity of the public key, which consists of only simple fast arithmetical operations. We call the cryptosystem NICE (New Ideal Coset Encryption). In this paper, we consider practical aspects of the NICE cryptosystem. Our implementation in software shows that the decryption time of NICE is comparably as fast as the encryption time of the RSA cryptosystem with e = 216+1. To show if existing smart cards can be used, we implemented the NICE cryptosystem using a smart card designed for the RSA cryptosystem. Our result shows that the decryption time of NICE is comparably as fast as the decryption time of RSA cryptosystem but not so fast as in software implementation. We discuss the reasons for this and indicate requirements for smartcard designers to achieve fast implementation on smartcards.

Fully secure doubly-spatial encryption under simple assumptions

Abstract: Recently, Hamburg improved the notion of spatial encryption by presenting a variant called doubly-spatial encryption As a generalization of the spatial encryption, the doubly-spatial encryption is more powerful and expressive More useful cryptography systems can be built from it, such as attribute-based encryption, etc However, the only presented doubly-spatial encryption scheme can only be proved to be selectively secure In this paper, we primarily focus on the full security of doubly-spatial encryption A doubly-spatial encryption scheme has been proposed We apply the dual system methodology proposed by Waters in the security proof Our scheme can be proved adaptively secure under standard assumptions, the decisional linear assumption and the decisional bilinear Diffe-Hellman assumption, over prime order groups in the standard model Our scheme is the first fully secure construction of doubly-spatial encryption As an independent interest, we also propose a fully secure spatial encryption with weak anonymity and constant ciphertext size in the composite order group settings

E-voting protocol based on public -key cryptography

Abstract: In this paper we propose a new secure E-Voting protocol based on public-key encryption cryptosystem. This protocol is summarized in three processes: firstly, access control process which involves the identification and authentication phases for the applied citizens. Secondly, the voting process which will be done by ciphering the voter information using public-key encryption cryptosystem (RSA), to be submitted over an insecure network to the specified government election server. Finally, the election server administrator will sort the final result by deciphering the received encrypted information using RSA private key. Actually, this E-Voting protocol is more efficient than others E-Voting protocols since the voter can vote from his/her own personal computer (PC) without any extra cost and effort. The RSA public-key encryption system ensures the security of the proposed protocol. However, to prevent a brute force attack, the choice of the key size becomes crucial.