A network management system (NMS) is a software application that helps monitor, control, and manage computer networks. It provides tools for network administrators to oversee network performance, detect issues, and ensure that all devices, such as routers and switches, are functioning properly. By using an NMS, organizations can maintain efficient communication and data flow within their networks. NMS typically includes features like fault management, configuration management, performance management, and security management. These functions help in identifying problems, optimizing network resources, and protecting against unauthorized access. Overall, an NMS is essential for maintaining the health and reliability of a network infrastructure.