Enhancement of KaPoW Plugin to Defend Against DDoS Attacks

DDoS attack is one of the hardest attacks to detect and mitigate in the computer world. This paper introduces two quantitative models, which use the client puzzling to detect and thwart application DDoS attacks. We simulated the models to use the probabilistic metrics to penalize the malicious users and prevent them from launching a DDoS attack while offering a stable environment to the normal users and decreasing the number of false positives and false negatives