Launching a denial of service (DoS) attack is trivial, but detection and response is a painfully slow and often a manual process. Automatic classification of attacks as single- or multi-source can help focus response, but current packet-header-based approaches are susceptible to spoofing. This paper introduces a framework for classifying DoS attacks based on header content, ramp-up behavior, and novel techniques based on spectral analysis. Although headers are easily forged, we show that characteristics of ramp-up and the attack spectrum are much more difficult to spoof. To evaluate our framework we monitored access links of a regional ISP over a period of five months, detecting 80 live attacks. Header analysis identified the number of attackers in 67 attacks, while the remaining 13 attacks were classified based on ramp-up and spectral analysis. We validate our results through monitoring at a second site, controlled experiments over the Internet, and simulation. We use experimen...
Alefiya Hussain, John S. Heidemann, Christos Papad