Affiliations: [a] Department of Computer Science and Engineering, National Institute of Technology, Jalandhar, Punjab, India | [b] Department of Information Technology, Jaypee University of Information Technology, Solan, Himachal Pradesh, India | [c] Department of Computer Science and Engineering, Shaheed Bhagat Singh State Technical Campus, Ferozpur, Punjab, India
Abstract: Our dependence on the internet for simple and time critical applications make availability of services a top security concern. There are many attacks to threaten the availability of service, but Distributed Denial of Service (DDoS) attack constitute one of the major and the most growing threat to severely degrade the system performance. DDoS defense has been matured over time and many solutions have been proposed to solve this problem. However, most of the research is focused on detecting and blocking this attack, which results in significant disruption before regaining system control and are not suitable for critical infrastructures. So, researchers come up with an interesting alternative, overlay based defensive approaches, which try to survive the attack by providing sustainable performance to the legitimate clients in attack situations. This article provides a review of the overlay based defensive techniques by categorizing them into two classes based on their underlying strategy: Proactive and Reactive approaches. The techniques within each category are discussed along with their advantages and disadvantages, and are studied comparatively with respect to relevant performance criteria. This paper also discusses the vulnerabilities of these architectures to guide the development of more robust procedures to combat DDoS attacks.
