College of Computer and Software Nanjing University of Information Science&Technology Nanjing 210044 China;
College of Electronic and Information Nanjing University of Information Science&Technology Nanjing 210044 China;
College of Electronic and Information Nanjing University of Information Science&Technology Nanjing 210044 China;
School of Geography Geology and the Environment Keele University Keele UK;
K-means clustering; self-organizing feature map neural network; network security; intrusion detection; NSL-KDD data set;