Research Of Network Security Based On Trust Evaluation For Industrial Wireless Network

With the rapid development of wireless sensor network technology and increasingly sophisticated, in the early 1990s, the wireless technology get into the field of industrial control systems, and became to the hot research topic of the industrial control systems; Industrial wireless technology with low cost, low power consumption easy subordinates, low maintenance costs and many others advantages, it’s have a large-scale widely used and cheerful prospect. Countries and a number of companies have join in the research and development of industrial wireless network technology, and there were multiple protocol standards are recognized internationally, which WIA-PA standards as our own intellectual property industrial wireless networking standard, and it was approved. That shown China in the field of industrial wireless network technology is already in one of the technologically advanced countries.Industrial wireless network WIA-PA as an emerging technology, with high real-time, high reliability, low power and low cost, at the time of all aspects of research continued to mature, there are exist some traditional hard technology problems in traditional wireless network, such as network security issues. Industrial wireless network WIA-PA with wireless communications transmission technology, and uses the 2.4GHz band communication shared, so it may exist some the potential variety external network attack, in addition to industrial wireless networks used in industrial areas, safe for normal operation and production are particularly important, therefore, ensure that the WIA-PA network security has very important significance. October 2011, China’s Ministry of Industry and Information Technology clearly made on "the strengthening of industrial control systems for information security management", and it makes network security has become a research topic to be solved for industrial wireless networks. The physical layer and MAC layer of WIA-PA protocol stack hierarchy is compatible with IEEE802.15.4 protocol, its security services play a protective role in WIA-PA network, and the use of encryption algorithms and key management, can effectively resist some typical external attacks, and effectively prevent a network of confidential data being stolen lead to leaks. However, the encryption algorithm and key management can’t be effective enforce the attacks launched by malicious nodes within the network. Therefore, an effective solution to the attacks of malicious nodes within the network, it is very important for the whole network and it played the role of last a firewall to protect network security.For improve network security, and timely detection the internal malicious node of network to resist the malicious nodes mort attack damage the network. I’m in-depth study of various solutions, analyze the advantages and disadvantages, and the specific application environment for the WIA-PA network characteristics, used the CONFIDANT safety program to realize it. According to the CONFIDANT security model and framework, used Bayesian mathematical and statistical analysis of the behavior of nodes in the network analysis and evaluation, and combined with the WIA-PA network technology, the paper proposed the way of separated statistical the node’s behavior and calculation the node’s evaluation base on data frame format, thereby eliminating the impact of node safety assessment on the network real-time and reliability; using the sliding window mechanism to calculate the credibility of the node, so that lowed the node’s recent behavior weight of its security value, and also avoid the node’s history behavior on the influence of the credit value, and enhance the freshness of the nodes credit value;proposed the method of two security threshold for processing nodes credit value. When the credibility of the nodes below the acceptable safety threshold timely start the detection mechanism on node energy, channel quality, node hardware failure, this way can reduce the false positive rate of the node and improve the precision of the malicious nodes evaluation within the network based on trust evaluation mechanism, makes it more suitable for the WIA-PA network application environment. For the existing need routing protocols DSR, secure routing protocols SDSR is combine the CONFIDANT security program base on the DSR protocol. The key process steps of security routing protocol SDSR was implementation in the paper. The CONFIDANT security program applicable to but not limited to DSR protocol.Finally, the paper showed the simulation experiments on CDSR protocol, and analyzed it. Based on Bayesian assessment methods TEB of the CONFIDANT security program can quickly and timely discovery the malicious nodes within the network, and can effectively prevent the destruction of the malicious node’s attacks of in the network; Compare to the SRP algorithm using in the routing network, the security routing protocol CDSR cost small on the network, the false positive rate of the nodes in the network is under 0.4%, thus indicating that the program is beneficial to strengthen the security of the WIA-PA network. At the end of the article, the paper made a research summary and outlook.