Improving Scanner Data Collection in P4-based SDN

Port scanning is a well-known behavior when a botnet searches target devices. To detect port scanning accurately, data with high discriminatory power are indispensable. Most related works, however, focus on data analysis methods but neglect storage limitations of switches, which makes their methods impractical. Therefore, we propose a new data collection method for collecting network information of port scanning in P4-based SDN named 0-replacement. Through simulations, we compare the 0-replacement method with two classic data collection methods. Results show that the 0-replacement method improves the true positive ratio by at least 25 percentage points but only consumes 0.36% memory space.