The use of packet inter-arrival times for investigating unsolicited Internet traffic

Monitoring the Internet reveals incessant activity, that has been referred to as background radiation. In this paper, we propose an original approach that makes use of packet inter-arrival times, or IATs, to analyse and identify such abnormal or unexpected network activity. Our study exploits a large set of data collected on a distributed network of honeypots during more than six months. Our main contribution in this paper is to demonstrate the usefulness of IAT analysis for network forensic purposes, and we illustrate this with examples in which we analyse particular IAT peak values. In addition, we pinpoint some network anomalies that we have been able to determine through such analysis.