<![CDATA[Distributed Denial-of-Service (DDoS) attacks remain a critical threat to network service availability, with SYN Flood being one of the most commonly exploited techniques targeting the TCP three-way handshake mechanism. This study aims to experimentally simulate SYN Flood DDoS attacks in a controlled virtual network environment and to analyze their impact on server performance. The experiment was conducted using the Metasploit Framework on Kali Linux as the attack platform and Ubuntu Server as the target system, deployed within a virtualized laboratory setup. System performance was monitored using top for CPU and memory utilization, while network traffic behavior was analyzed using Wireshark. Experimental results indicate a significant increase in CPU usage (from approximately 2% under normal conditions to over 11% during the attack), a noticeable reduction in available memory, and the accumulation of half-open TCP connections caused by repetitive SYN packets without corresponding ACK responses. These effects resulted in temporary service unavailability on the targeted ports. The proposed experimental framework provides practical insights into the operational behavior of SYN Flood attacks and serves as a reproducible laboratory reference for cybersecurity education and preliminary mitigation studies. It should be noted that the experiments were conducted in a virtual environment with predefined parameters, and the results may not fully represent real-world production networks.]]>
