With the rapid development of Internet technology, network security issues such as hacker attacks, ransomware, and DDoS attacks have gradually come into public view. This paper sorts out two core defense technologies—firewall tech-nology and Intrusion Prevention System (IPS)—from the perspectives of tech-nical principles, development trends, and application scenarios. Meanwhile, combined with current network security hotspots such as zero-day vulnerabili-ties and AI-driven attacks, it analyzes the challenges and development trends faced by the aforementioned defense technologies.