Be sure to perform a 'sanity check' of what PeakHour is reporting vs. what you expect to see. Some router manufacturers are a little lazy when it comes to ensuring they report throughput accurately, so it makes sense to double-check. If you suspect PeakHour is under or over-reporting usage, try the steps in this FAQ to determine if the data is accurate: PeakHour isn't seeing my UPnP router / isn't reporting bandwidth / appears to be reporting incorrectly. How can I check if it's working properly?
My Internet Router supports SNMP - what can I monitor?
These types of devices are relatively easy to monitor as they either support SNMP or can have SNMP enabled.
Check out our guide: I'd like to monitor my Mac/PC/Linux devices. How can I enable them for SNMP? for more information.
I want to monitor my iPhone/iPad/Android phone/PlayStation/Xbox etc.
"Appliance"-like devices that don't support running SNMP or UPnP can't generally be monitored as there is no way to query them.