Network monitoring tools are used to monitor and identify network issues. They are also used to monitor the performance of the network. Network monitoring tools can be classified into two categories:

Passive Network Monitoring Tools:

These tools only monitor the network traffic. They do not interfere with the traffic in any way, they just analyse it and provide reports on what is happening in the network.

Active Network Monitoring Tools:

These tools actively interfere with traffic in order to find out what is happening with the network. They may make changes to how data is transmitted or even stop certain types of traffic altogether.