LAUSR

Cloud computing is an essential technology for the future of the Information Technology (IT) industry. However, the cloud security level is identified as the biggest challenge facing cloud providers and a major concern for cloud adopters. Economic Denial of Sustainability (EDoS) attack is one of the major threats targeting the cloud. The EDoS attack exploits the cloud elasticity and auto scaling features to charge a cloud adopter bill an excessive amount of cost leading to large-scale service withdrawal or bankruptcy. A novel reactive approach referred to as the EDoS Attack Defense Shell (EDoS-ADS) is proposed to mitigate EDoS attacks while taking into account most of the existing mitigation techniques drawbacks. Specifically, the EDoS-ADS has the ability to identify the legitimacy of clients even if they belong to a Network Address Translation (NAT) based network. Thus, EDoS-ADS is the first known technique that effectively prevents an EDoS attack from blocking an entire NAT-based network from accessing the cloud. The EDoS-ADS effectiveness in terms of response time, CPU utilization, throughput, and cost is evaluated using a CloudSim simulator. The simulation results show that EDoS-ADS outperforms other mitigation techniques, and successfully differentiates between legitimate and attacker clients even when they belong to the same NAT-based network.