How to monitor traffic on the local network?

Question

Computer networks

Good afternoon!
I have a small local area network in my company. (Photo below)
I came to the conclusion that I want to monitor traffic both on the local network, and see who climbs the network and why,
See who loads the network the most and limit users!
All the equipment that is now worth quite simple.
Please provide a budget solution for this!

Answer 1

Keywords - netflow , mirroring port , sniffer .
What your equipment can do - see for yourself. Sniffer is free (wireshark as an example).

Answer 2

You have a switched network, it makes no sense to catch / monitor traffic between computers, almost all switches are able to digest traffic from all ports at the same time.
In your case, it is enough to monitor traffic only on the side of the router. There is a bunch of software for this, starting with polling via snmp (cacti) and ending with collectd + iptables plugin (a service installed on a Linux router). I'm for the last option. Collectd also needs a renderer to work properly. I suggest influxdb + grafana - https://www.linkedin.com/pulse/monitoring-collectd...