【作者】 卢洁；

【导师】 张浩平；

【作者基本信息】 南京林业大学 ， 测试计量技术及仪器， 2008， 硕士

【摘要】 随着网络的普及,人们在日常生活和工作环境中对计算机网络越来越依赖,网络的安全性也越来越引起人们的关注。当前网络安全防护技术大多是被动的防御技术。而作为主动且动态的网络安全防御技术——入侵检测技术,是网络安全技术发展的一个新方向,是被动防御技术的必要补充。本文阐述了一种入侵检测的新策略,通过分析现有的入侵检测技术和通用的入侵检测框架,发现基于人工神经网络的入侵检测是一种有效的入侵检测方法。因此在本文中,采用径向基函数(RBF)神经网络技术对入侵行为进行检测,他具有最佳逼近能力、网络结构简单、学习速度快的优点,但RBF神经网络的参数设置是基于参数空间局部信息的,不是全局最优值,这必将降低入侵检测效率。本文分析了具有全局寻优的功能PSO算法,该算法能够改进传统的RBF神经网络学习策略,可以弥补RBF神经网络参数设置的不足。在此基础之上,研究了基于PSO-RBF神经网络的入侵检测系统所需要解决的研究层面的问题,设计了一个原型系统。利用这个原型系统,从层次、模块两个维度分别对他的设计进行了介绍,同时对实现技术进行了讨论,并给出了部分模块的主要实现方法。目前本文已经实现了系统的封闭测试并探讨了如何对系统进行开放测试。实验结果表明,基于PSO-RBF神经网络的入侵检测系统有效的提高了入侵检测的效率。最后,通过对基于PSO-RBF神经网络的入侵检测系统研究、设计与实现的内容总结,本文指出了今后发展和改进的方向。更多还原

【Abstract】 With the widely spread of internet, the everyday life and the working environment of people are having increasing dependence on the computer network, and thus the security of network is gaining more attentions of people. The current security defense techniques are mainly passive defense techniques. As an initiative and dynamic network security defense technique, the intrusion detection technique is a new direction of the development of network security, and is a necessary complementary of conventional network security techniques.This paper introduces a new strategy of Intrusion detection. Through the analysis on the existing intrusion detection and common intrusion detection framework, I notice that, NN-based intrusion detection technique is an efficient method. So, I adopt the RBF-NN, which has the best approaching capability, simple network structure, and high leaning speed. But the parameters of RBF are based on the partial information in the whole parameter space, thus it may not be able to reach the global optimal value and reduces the detection rate. This paper analyzes the functions of PSO algorithm which has the capability to search the global optimal solution, the PSO algorithm can modify the study strategy of RBF-NN and it can fix the loophole of the parameters setting in RBF-NN. Based on this, I further study the research problems which need to be solved in the PSO-RBF NN based intrusion detection system, and design a prototype system. With this prototype system, I illustrate the implementation of the system from the perspective of hierarchy and modules. And I also present the design diagram and supporting techniques. For the major modules, I show the detailed implementation methodology. Now I have completed the close-test and discussed how to do the open-test. The experimental results show that, the intrusion detection system based on PSO-RBF NN can effectively enhance the efficiency of intrusion detection. Finally, through the conclusion on the research, design and implementation of PSO-RBF NN based intrusion detection system, I point out the possible future work.更多还原