Network security can involve a variety of complex technologies and disciplines, often managed by separate teams and third parties. Client-server traffic can be impacted at many points along the path, and it’s not always obvious where to troubleshoot when there are problems. Taking shots in the dark or jumping to conclusions wastes time and resources. This talk presents a systematic approach to network security troubleshooting, working through the stack in a deliberate fashion, to narrow down root causes quickly and accurately.