Network monitoring tools are essential for capacity planning, as they provide real-time and historical data on the network's status, performance, and usage. They can help network engineers identify bottlenecks, anomalies, trends, and patterns that affect the network's capacity and quality of service. These tools feature traffic analysis, which enables engineers to measure the volume and type of traffic that flows through the network and how it is distributed among different devices, protocols, and applications. This helps them determine bandwidth requirements, optimize routing, and prioritize traffic based on its importance and sensitivity. Additionally, device health monitoring allows engineers to track availability, uptime, and performance of the network devices like routers, switches, firewalls, servers, and load balancers. It can help them detect and troubleshoot any issues that may affect the network's functionality. Lastly, resource utilization tracking allows engineers to monitor consumption of resources like CPU, memory, disk space, and power. This helps optimize resource allocation; plan for upgrades; and prevent overloading or underutilization of the network devices.