A Cost Effective Economic Denial of Sustainability (EDoS) Attack Mitigation Framework for E-Commerce Applications in Cloud Environments

Abstract

The promise of pay-as-you-go and scalable model of Cloud Computing has at- tracted a large number of medium and small enterprises to adopt E-Commerce model of conducting on-line businesses. While E-Commerce applications on the Cloud expand businesses by making them more widely accessible, they also makes these applications susceptible to economic denial of service at- tacks - a form of application layer attacks that drive up the cost of Cloud computing by using up application resources. This paper focuses on de- tection and mitigation of EDoS for E-Commerce based applications. EDoS is di erent from traditional DDoS in that, the intention of the latter is to consume all the resources (like memory, bandwidth, CPU etc) of the Web Server thus making it unavailable to its legitimate users. EDoS on the other hand is caused by malicious users who are not interested in following the regular work ow of an E-commerce application by purchasing items but by employing it for their own purposes of entertainment, price-checks and idle sur ng. We have a twofold solution, (i) admission control and (ii) congestion control. In the rst, we limit number of clients that can simultaneously send requests, thus allowing only enough clients that can be served easily within available resources on the Web server. In the second, we change the priority of allowed clients based on the type of resources they visit and type of ac- tivities they perform, thus making the maximum resources available to good clients. Our contribution is two-fold: (1) We model the work ow of a typical E-Commerce application and identify key parameters that identify good and bad users and (2) we present the design of a learning-based classi er that distinguishes good and bad users depending on the values of the parameters they select while web browsing. We have integrated and evaluated this so- lution in a Web Application Firewall and found it quite e ective in term of resources distribution among good and bad clients.