Inferring Internet denial-of-service activity

TLDR

The study aims to quantify the prevalence of Internet denial‑of‑service attacks to understand current threats and support long‑term trend analysis. The authors introduce backscatter analysis, applying it to 22 multi‑week traces from 2001‑2004 to estimate worldwide DDoS activity and characterize attack characteristics. They estimate over 68,000 attacks against more than 34,000 distinct IPs, including major e‑commerce sites and small ISPs, marking the first comprehensive quantitative assessment of global DDoS activity.

Abstract

In this article, we seek to address a simple question: “How prevalent are denial-of-service attacks in the Internet?” Our motivation is to quantitatively understand the nature of the current threat as well as to enable longer-term analyses of trends and recurring patterns of attacks. We present a new technique, called “backscatter analysis,” that provides a conservative estimate of worldwide denial-of-service activity. We use this approach on 22 traces (each covering a week or more) gathered over three years from 2001 through 2004. Across this corpus we quantitatively assess the number, duration, and focus of attacks, and qualitatively characterize their behavior. In total, we observed over 68,000 attacks directed at over 34,000 distinct victim IP addresses---ranging from well-known e-commerce companies such as Amazon and Hotmail to small foreign ISPs and dial-up connections. We believe our technique is the first to provide quantitative estimates of Internet-wide denial-of-service activity and that this article describes the most comprehensive public measurements of such activity to date.