Cipher

About: Cipher is a research topic. Over the lifetime, 9409 publications have been published within this topic receiving 110309 citations. The topic is also known as: cypher & cryptographic algorithm.

Comments on “Theory and applications of cellular automata in cryptography”

Abstract: The cipher systems based on Cellular Automata proposed by Nandi et al are a ne and are insecure Index Terms Cryptography block ciphers stream ciphers cellular automata

System for enciphering and deciphering data

Abstract: A system and method for transmitting enciphered data between first and second terminals over a data transmission channel. The system comprises a transmitter located at the first terminal, a receiver located at the second terminal and cipher computers located at each of the first and second terminals. At least one of the cipher computers is programmable and has a program memory. Storage means are provided for storing a program code or algorithm and a secret cipher key, and means are further provided for transmitting the algorithm to the programmable computer for storage in its program memory. The data transmitted between the first and second terminals is enciphered in accordance with the algorithm stored in the program memory of the programmable computer and determined by the secret cipher key.

An image encryption algorithm based on compound homogeneous hyper-chaotic system

Abstract: Compound hyper-chaotic system is a chaotic system that combines two or more hyper-chaotic systems. In this paper, we propose a 2-dimensional compound homogeneous hyper-chaotic system (CHHCS) and local binary pattern (LBP)-based image encryption algorithm, which includes the CHHCS-based permutation operation and the LBP-based diffusion operation. Firstly, we employ a new CHHCS and prove the good hyper-chaotic behaviors, and we use CHHCS to permutate the plain image twice to obtain good permutation effect. Then, every permutated pixel is diffused with dynamic LBP operation, which means even the same permutated pixel will be encrypted to different cipher value. Finally, we provide some theoretical analyses and simulations to confirm the security and the validity of the proposed algorithm.

Communication network for encrypting/deciphering communication text while updating encryption key, a communication terminal thereof, and a communication method thereof

Abstract: In a cryptosystem which performs encryption/deciphering of communication text using k bits of cryptographically secure pseudo-random numbers as the block cipher key thereof, the block cipher key is updated each time j=k/m bits of new pseudo-random numbers are generated, with the j·m=k bits of pseudo-random numbers created by combining the j·(m−1) bits within the k bits of the present key and the newly generated j bits, serving as a new key, thereby shortening the updating cycle and improving the safety. Also, by sending the number of times of generation of pseudo-random numbers along with the encrypted communication text from the sending side, and by the receiving side using from the sequentially generated pseudo-random numbers, pseudo-random numbers generated after the received number of times of generation as the new key, deciphering can be performed regardless of the order to reception, in the event that a plurality of cipher texts are sequentially sent while updating the encryption key.

On the Construction of Variable-Input-Length Ciphers

Abstract: Whereas a block cipher enciphers messages of some one particular length (the blocklength), a variable-input-length cipher takes messages of varying (and preferably arbitrary) lengths. Still, the length of the ciphertext must equal the length of the plaintext. This paper introduces the problem of constructing such objects, and provides a practical solution. Our VIL mode of operation makes a variable-input-length cipher from any block cipher. The method is demonstrably secure in the provable-security sense of modern cryptography: we give a quantitative security analysis relating the difficulty of breaking the constructed (variable-input-length) cipher to the difficulty of breaking the underlying block cipher.