Tracking the activity of network users

Question

Computer networks

Good afternoon,

A regular school (80 regular users in the grid plus students in computer classes) is looking for software (preferably free) to track activity and use of the network. What we want:
- track the number of connected devices (of course in online mode)
- graph of the load on the grid (how much we download, within the network or from the Internet)
- the ability to see the current information for each of the clients.

What is?
Decent computers, gateway THOMSON TG789vn, access point LINKSYS WAP54G. There is a raised domain server, but not everyone is connected to it yet, and in theory it will continue to be so (there are computers outside the domain). The THOMSON TG789vn device keeps statistics but is not online.

The ability to knock out a client would be great, but it's not that important.

Be happy!
We will be extremely grateful for your help.

Answer 1

If without cutting down the subscriber, www.zabbix.com is suitable for you , the number of active devices, load, network map, everything is there.

Answer 2

If the task is as in the title, then a very handy netmap tool. At a glance, you can see the turn-on times for up to 40 computers in a few hours - up to a day. by clicking once - you can see for yesterday. Program limitation, like 42 or 46 computers.