Defending Against TCP SYN Flooding Attacks Under Different Types of IP Spoofing

TCP-based flooding attacks are a common form of Distributed Denial-of-Service (DDoS) attacks which abuse network resources and can bring about serious threats to the Internet. Incorporating IP spoofing makes it even more di..cult to defend against such attacks. Among di..erent IP spoofing techniques, which include random spoofing, subnet spoofing and fixed spoofing, subnet spoofing is the most di..cult type to fight against. In this paper, we propose a simple and e..cient method to detect and defend against TCP SYN flooding attacks under di..erent IP spoofing types, including subnet spoofing. The method makes use of a storage-e..cient data structure and a change-point detection method to distinguish complete three-way TCP handshakes from incomplete ones. Simulation experiments consistently show that our method is both efficient and e..ective in defending against TCP-based flooding attacks under di..erent IP spoofing types.