Internet provides many critical services so it has become very important to monitor the network traffic so that the resources of the network can be prevented from being depleted from malicious hackers. In this paper, the authors have presented a mechanism to detect and defense a web-server against a Distributed Denial of Service (DDoS) attack. They have presented simulation of specific kind of DDoS attack i.e. identity spoofing and SYN flood attack on an application similar to shopping portal and its results to demonstrate the effectiveness of the mechanism. Then, the attack is monitored in resource monitor of the server side monitor showing CPU utilization.