We present a code-based public-key cryptosystem, in which we use Reed-Solomon codes over an extension field as secret and disguise it by considering its shortened expanded code the base field. Considering provides safeguard against distinguisher attacks based on Schur product. Moreover, without using cyclic or quasi-cyclic structure obtain key size reduction of near...

A mobile ad hoc network (MANET) is a wireless communication network, which does not rely on any centralized management or a pre-existing infrastructure. Various key management authorities distributed over the network, each with a periodically updated share of the secrete key, is usually adopted. Thus many efforts have been made to adapt key management authority’s tasks to the dynamic environmen...

Not surprisingly, the common use of any public key crypto system involves publishing the public key and keeping the private key secret. There are however a few applications where both the private and public key are kept secret, thereby effectively converting a public key crypto algorithm to a symmetric algorithm. We show that if the RSA cryptosystem is used in such a symmetric application, it i...

We present a chosen-ciphertext attack against the public key cryptosystem called NTRU. This cryptosystem is based on polynomial algebra. Its security comes from the interaction of the polynomial mixing system with the independence of reduction modulo two relatively prime integers p and q. In this paper, we examine the effect of feeding special polynomials built from the public key to the decryp...

We propose a new variant of the McEliece cryptosystem which ensures that the code used as the public key is not permutationequivalent to the secret code. This allows to increase the security of the public key, and to reconsider possible adoption of classical families of codes, like Reed-Solomon codes. A reduction in the key size or, equivalently, an increased level of security against informati...

In 1984, Shamir [1] introduced the concept of an identity-based cryptosystem. In this system, each user needs to visit a key authentication center (KAC) and identify him self before joining a communication network. Once a user is accepted, the KAC will provide him with a secret key. In this way, if a user wants to communicate with others, he only needs to know the “identity” of his communicatio...

ii I certify that I have read this dissertation and that in my opinion it is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. I certify that I have read this dissertation and that in my opinion it is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. I certify that I have read this dissertation and that ...

Abstract Chaos i s introduced to cryptology. As an example of the applications, a secret key cryptosystem by iterating a one dimensional chaotic map i s proposed. This system is based on the characteristics of chaos, which are sensitivity of parameters, sensitivity of initial points, and randomness of sequences obtained by iterating a chaotic map. A ciphertext is obtained by the iteration of a ...

A chaotic map has sensitivity to changes in the initial conditions and parameters, and a long-term forecast becomes impossible by iterating a chaotic map. These features look similar to the features of cryptology. For this reason, it is effective to use chaotic maps for cryptosystems. In this research, we investigate features of the modified cut map when the parameters αi are changed. We use th...

Chaotic systems are vital in designing contemporary cryptographic systems. This study proposes an innovative method for constructing effective substitution box using a 3-dimensional chaotic map. Moreover, bouyed by the efficiency of proposed chaos-based boxes’ effectiveness, we introduce new image cryptosystem that combines adeptness Gray codes, non-linear and sensitive hyper-chaotic system, S-...