摘要
OCSVM适合无监督情况下的孤立点检测,与入侵检测问题有很大的相似性.文章研究了OCSVM在网络入侵检测中的应用,探讨了模型优化的两个主要方面.提出的二阶段模型参数选取方法,能够比GA算法更快地搜索到近似全局最优参数;采用GA算法提取出22个TCP/IP连接的重要特征,比较了采用特征子集和全部特征的OCSVM的检测精度、训练测试时间.实验表明,给出的OCSVM模型优化方法,能够获得优异检测性能,具有更优的训练和检测效率,意味着可以应用到实时网络入侵检测系统.
As an unsupervised learning algorithm, OCSVM is suitable for detecting outliers, which is similar with problems of intrusion detection in nature. This paper focuses on the application of it in network intrusion detection, makes detail researches on model optinlization of it. A method called "two-phase model selection" is proposed for searching approximately global optimal parameters, which is faster than classical GA methods. Further, 22 important features of TCP/IP are extracted through GA algorithm; detection accuracy and costs are compared between OCSVMs trained on feature subset and on all features, respectively. The results of experiments show that our method of model optimizing can be used in real-time network intrusion detection, having the advantages of excellent detection performance and reduced training/detection periods.
出处
《韩山师范学院学报》
2009年第3期49-53,共5页
Journal of Hanshan Normal University
关键词
入侵检测
OCSVM
参数选择
特征提取
intrusion detection
OCSVM
parameter selection
feature extraction