Abstract
Cloud computing is currently one of the fastest growing segments of IT. To date, and according to a recent survey conducted by the International Data Corporation, security is the biggest challenge to cloud computing. A cloud introduces resource-rich computing platforms, where adopters are charged based on the usage of the cloud's resources, known as "pay-as-you-use" or utility computing. However, a conventional Distributed Denial-of-Service (DDoS) attack on server and network resources compromises cloud computing services by charging cloud adopters more cost due to the attack activities that consume cloud's resources. In such case, the main goal of such attack is to make the cloud computing unsustainable by targeting the cloud adopter's economic resources. Thus, it constitutes a new breed of DDoS attacks, namely Economic Denial of Sustainability (EDoS) attack. In this paper, we study the impact of EDoS attacks on the cloud computing services, considering only a single class of service. We developed an analytical model verified by a simulation model to study such impact of EDoS attacks on the cloud computing. The analytical model relies on the queuing model that captures the cloud services and considers a number of performance and cost metrics including end-to-end response time, utilization of computing resources, throughput, and the incurred cost resulting from the attack.