Intrusion detection system using Discrete Fourier Transform

Intrusion Detection System (IDS) detects attacks using pattern files which are known as “signature”. Effectiveness of detection depends on the kind of signature. In this paper, we propose a signature generation method using Discrete Fourier Transformed regards payload between client and server as discrete waveform. Regarding normal communication spectrum as noise, we can clarify the characteristics of attack sessions. From the viewpoint of spectrum analysis, our method detect unknown attack session. The proposed method simulated using Kyoto2006+ dataset which is currently used as intrusion detection evaluation. As the result, we have 5% of false positives for detecting attacks.