Research On Key Technologies Of Information Transmission For Internet Of Things Control System

With the rapid development of control technology, network technology and computer application technology, the network control system has became the new control system, which have got the more concern from the control area. The concept and the technology continuous emergence for the Internet of Things (IOT), provide the new opportunities and challenges for the development of network control system. The control system based on the IOT, it is to say the Internet of Things control system (IOT-CS), will become one of the next generation of the control system.Compared with network control system, the greatest charm of the IOT-CS is the target of the secure mobile monitor and the secure mobile control. That is to say, any authorized person or equipment, at any place, any time, always can securely control and monitor the equipment, at the same time, the equipment can be controlled in order to achieve the control purposes, which is referred to as the target of "3-any" and "1-control". In order to achieve this target and apply the system in the actual production, there are three key technologies must be achieved.The first issue is the access security. The entire system should only allow authorized people or equipment, can access to the IOT-CS at anytime and anywhere, and reject illegal user or device access to it. That will ensure the security of the monitoring and control.The second issue is the transport security. The IOT-CS should make sure the information in the transmission with the confidentiality, the integrity, and the non-repudiation. That will ensure the information transmission security and the control system services security.The finally issue is delay stability control. The IOT-CS should eliminate the influence of the delay from information transmission and decision-making processing in the entire control system. That will ensure the stability and robustness of the whole control system.The Purpose of this paper is to achieve these three key technologies.Through researching and anglicizing the development process and the development trend of network control system, this paper draws the conclusion that the IOT-CS will be the new development direction of next generation control system. On basis of this, the initial definition, the work course, the basic structure, the use advantages and the several key issues of the IOT-CS are discussed in the paper.In order to solve the issue of the access security and some transport security, the paper analysis the IPSec VPN protocol, and pointes out the defects of the IPSec, which are the IPSec can not traverse NAT protocol and can not meet the3-any target in the IOT. In order to solve these defects, the paper presents an improvement of the IPSec, which is the IDSec. Through the discussion of the structure, the process and the application mode of the IDSec, the paper Demonstrate that the IDSec is entirely feasible for the access safety and the information transmission security in the IOT-CS. and through specific procedures and test results, this paper confirms this conclusion. At last, the concept of generalized IDSec is proposed in the paper, the generalized IDSec breaks the limitations that IPSec only supports the IP transport protocol. So, the generalized IDSec is the security protocol nothing to do with the network layer transport protocol. And it has a strong practical and adaptable.In order to solve the issue of information security transmission, this paper researches and analysis the attack methods of the modern block cipher algorithm, which are basis on the one-to-one relationship between plaintext and ciphertext. Then, through improving the use modern of block cipher algorithm, a time-varying cryptographic algorithm is proposed by this paper, which is based on the time variable.. This algorithm can effectively undermine one-to-one relationship between theplaintext and ciphertext, which will increase the difficulty to decipher the entire security system by illegal attacker. The three key aspects in the algorithm is discussed by this paper. And algorithm implementation process is described. Through the specific implementation and performance analysis, the usefulness and the adaptable of Time-varying cryptographic algorithms is confirmed in this paper.In order to solve the issue of the delay stability control, Smith predictor is analyzed and the concept of generalized Smith predictor is proposed. According to this concept, the theoretical model of the differential predicts Smith predictor is proposed. But, this theoretical model is not conducive to the practical application, so this paper simplies it and gets an eventually differential prediction Smith predictor. Then, the paper uses the gray prediction algorithm as predict aspects of the differential prediction Smith predictor in the experiments. It can be seen from the results of experiments, this model can effectively achieve the goal of the generalized Smith predictor, which will be able to effectively weaken the lag delay of the whole control system. At the same time, this model also solves the problems that the traditional Smith predictor requires the model precision.The IOT-CS has many advantages, such as simple assembly, interactive shortcut, easy expansion and diagnostic accuracy. The IOT-CS is the extension and expansion of the modern network control system. It can be predicted that in the manufacturing and the intelligent home, the IOT-CS and its technologies will have huge commercial value. And then, the IDsec protocol, the time-varying cryptographic algorithm and the delay control technology, will also have a positive effect in the other industries of the IOT, the development of the control link and the control method in the mechanical design.