To get down to the level of what device is doing what on the network you would need to use something such as NetFlow or devices with SNMP reporting. If each device is connected to individual switch ports. Then go with a SNMP reporting process. If the devices are on a shared medium such as WiFi then you would want to use NetFlow. The difficulty is that NetFlow and SNMP are usually only found on higher end gear. So you need to have invested in networking gear that supports these features. NetFlow would be best when running on the router or firewall and SNMP on the Ethernet switch. On option for a SNMP tool would be the Cacti.net product. You could add a NetFlow option to Cacti but I haven’t tried that yet. There are other NetFlow freeware graphing options out there.