Trawling traffic under attack overcoming ddos attacks by target-controlled traffic filtering

Shlomi Dolev, Yuval Elovici, Alex Kesselman, Polina Zilberman

International Journal of Foundations of Computer Science 22 (05), 1073-1098, 2011

As more and more services are provided by servers via the Internet, Denial-of-Service (DoS) attacks pose an increasing threat to the Internet community. A DoS attack overloads the target server with a large volume of adverse requests, thereby rendering the server unavailable to “well-behaved” users. In this paper, we propose two algorithms that allow attack targets to dynamically filter their incoming traffic based on a distributed policy. The proposed algorithms defend the target against DoS and distributed DoS (DDoS) attacks and simultaneously ensure that it continues to serve “well-behaved” users.In a nutshell, a target can define a filtering policy which consists of a set of traffic classification rules and the corresponding amounts of traffic for each rule. A filtering algorithm is enforced by the ISP’s routers when a target is being overloaded with traffic. The goal is to maximize the amount of filtered traffic forwarded …