Improvement Of Aes Encryption Algorithm And Linux Program Design In Embedded Monitoring System

With the development of social and advancement of science and technology,the progress technology of Internet of things changed with each passing day and made the monitoring system widely popularized.On the basis of previous technique,this paper designs an intelligent monitoring system to control and manage of system temperature and humidity and hardware facilities based on Exynos4412 target board and ZigBee wireless communication technology,and in order to protect the security of data in database,the AES algorithm is applied to the database encryption.In this paper,main works are as follows:(1)The paper has studied on the SQLite database of monitoring system.Firstly,the optimization of AES algorithm is proposed,the multiply operations are replaced by shift and XOR operations in the MixColumn.Moreover,the test program and complexity analysis show that the improved algorithm is more efficient than the algorithm before the improvement.Secondly,the safe strategy of counteracting the Square attack is given to enhance the security and prevent the algorithm from being attacked by Square.Finally,the experiments are presented to verify the effectiveness of the algorithm.(2)Based on Exynos4412 target board,the hardware platform of monitoring system is built and the porting of embedded Linux operating system and drivers are completed.Firstly,the working principle of Bootloader is applied to design and write the startup program,and the porting steps about Bootloader is given according to Exynos4412 target board,and the kernel is tailored and recompiled according to the requirements of actual project,and make the root file system by Busybox.Secondly,the steps of construction about BOA server,video server and SQLite database are provided according to the functional requirements of system.Thirdly,use the fastboot tool to complete the system transplant.(3)The application layer of monitoring system is designed by using modular programming ideas and multi-thread technology.Firstly,design and write the CGI program and BOA server program to realize the remote monitoring,and the program of ZigBee wireless sensor network is given to realize the data collection and transmission.Secondly,according to the type of message in the message queue to call different threads,the data receiving thread,the data analyzing thread and the data updating thread cooperate with each other to complete the work of data processing,the database thread mainly completes the store of data,and the device driver thread completes the work of device drivers.Finally,the system debugging is completed based on the Internet of Things platform in the laboratory.