Research On Security Protection Strategy Of Data Transmission Based On Internet Of Things

Internet of things is to collect information in real time through sensor technology and all kinds of network access,and realize information sharing through communication between nodes.Different from the traditional Internet,the Internet of things is closely connected with things and people.However,due to the openness of the Internet of things and the way of wireless communication between nodes,data in the transmission process is vulnerable to information tampering attacks,replay attacks,denial of service attacks and man in the middle attacks,resulting in the reduction of information integrity,confidentiality and availability,seriously affecting the life and property security of Internet of things users,even threatening the national security.Therefore,all industries pay more and more attention to communication security.Data encryption is an important research direction in the field of security.It is of great significance to protect the security of data after being attacked.The main work of this paper is as follows:First of all,this paper analyzes the threats to the data transmission of the Internet of things under the current network situation,and summarizes the means of information security protection in practical application.Due to the changeable virus,the external attack can not be completely prevented,there is no protocol that can not be broken completely,data encryption is almost the only way to ensure the confidentiality of information.In the process of transmitting confidential information,even if the data is leaked,because the plain text is encrypted into disordered cipher text,the real data can not be transmitted outside,so as to ensure the integrity and confidentiality of the data.On this basis,this paper takes AES(Advanced Encryption Standard)as the starting point,analyzes its encryption steps and shortcomings,and analyzes the improved research direction according to the development status and chaos theory.Next,the paper analyzes the core component of AES——S-box.Because S-box is responsible for byte substitution of AES,its cryptography performance directly affects the security strength of the whole encryption algorithm.The S-box generated by traditional way has high time complexity,which severely affects the security of thealgorithm.In this paper,after analyzing several common intelligent algorithms,we choose PSO for this part because of its unavoidable convergence.After analyze the optimization,we find that genetic algorithm could help to solve problems from PSO.The genetic algorithm's selection cross mutation mechanism is added to the optimization to improve the cryptographic performance of the optimization results.MATLAB simulation experiments are carried out to analyze the nonlinearity and difference uniformity of S-box.In addition,we put some other algorithms for comparison,which definitely prove that our idea could construct strong S-box with great cryptography performance.Finally,aiming at the security defect of the strong correlation between rounds of keys in AES encryption algorithm,the sequence obtained by logistic and tent iteration of one-dimensional chaotic mapping is designed to replace the original round of key expansion,and the irreversibility of AES key expansion is enhanced.The average pixel of the image to be encrypted is used as a parameter to substitute the initial value into the expression of chaotic sequence,so that the encryption process is related to the plain text image.Taking the chaotic sequence generated by Logistic chaotic map as the initial key,the security of the algorithm is improved.Through MATLAB simulation programming,the encrypted cipher text is compared and evaluated.Experimental results show that the algorithm has good encryption performance and large key space,and can literally resist the common attacks and analysis in the Internet of things.