Design And Implentation Of Lightweight Block Cipher System Based On Combined Chaos

The rapid development of the Internet of Things makes how to use cryptography technology to conduct secure and efficient information transmission on resourceconstrained devices,which has become a research hotspot.Resource-constrained devices refer to a type of hardware with small size,weak storage and processing capabilities.Block ciphers have become the significant method of encryption due to the excellent scalability of plain-text.S-boxes have a key impact on the security of block ciphers.However,the performance of S-boxes constructed by traditional algorithms is not excellent,and traditional block ciphers have high computational complexity that resource-constrained devices cannot afford it.How to design a secure and lightweight block cipher algorithm with low computational complexity has great research significance and value.The main research contents of this paper are as follows:(1)Aiming at the problem that traditional chaotic systems are not suitable for the design of lightweight block cipher algorithms,a new combined chaotic system is proposed,which overcomes the shortcomings of simple structure of low-dimensional chaotic systems and high iterative computational complexity of high-dimensional chaotic systems,Taking into account the design principles of password efficiency and security,the designed composite chaotic system has been proved by experiments to have excellent chaotic performance and can be applied to the design of lightweight block ciphers.(2)Aiming at the problem of low encryption security caused by poor S-box performance in cryptographic algorithms,this paper proposes an S-box construction and optimization algorithm based on an improved genetic algorithm with a combined chaotic system.The construction algorithm introduces misplacement minus random number generation and Standard mapping to solve the problem of reduced security in the construction of chaotic sequence S-boxes.In order to solve the problem of single optimization goal of traditional genetic algorithms,the optimization algorithm improves the traditional genetic algorithm including S-box encoding method,selection rate,crossover rate,and mutation rate.Experiments show that the optimized S-box performance has been greatly improved,and it can be applied to the design of lightweight block cipher algorithms.(3)Aiming at the encryption problem of traditional block cipher algorithms that are not suitable for resource-constrained devices due to their high complexity,based on the compound chaotic system,a lightweight encryption and decryption structure,round function,diffusion layer,and key expansion are proposed.Through the confusion and diffusion analysis of the block cipher algorithm,key space analysis,key sensitivity analysis,anti-differential attack analysis,anti-linear attack analysis,anti-algebraic attack and statistical analysis of ciphertext,the grouping proposed in this paper is proved The cryptographic algorithm is secure;Through analyzing the software and hardware implementation of the block cipher algorithm,calculating the number of gates consumed,the proportion of runtime memory,and the encryption speed,which proves that the cryptographic algorithm proposed in this paper is efficient and suitable for resource-constrained applications.The encryption of equipment has practical value.(4)A lightweight block cipher system was designed and implemented,and a wireless sensor simulation platform was built based on a single-chip microcomputer.The proposed cipher algorithm was simulated on the platform,and the results proved that the cipher algorithm can be used on resource-constrained devices with excellent application prospects.