PRTG Traffic Grapher - User Manual
How Packet Sniffing works
If you need to know what applications or IP-addresses are causing the traffic in your network you can use a Packet Sniffer which looks at every single data packet traveling in your network for accounting purposes.
PRTG can analyze the packets passing the network card of a PC or it can be connected to a so-called monitoring port of a switch.
In order to calculate bandwidth usage PRTG inspects all network data packets either passing the PC's network card (shown on the left side) or the data packets sent by a monitoring port of a switch (right side) with its built-in Packet Sniffer.
From the three bandwidth monitoring technologies this one creates the most CPU and network load and thus should only be used in small to medium networks or for individual computers.
What is PRTG Traffic Grapher?
PRTG Traffic Grapher is an easy to use Windows software for monitoring and classifying bandwidth usage. It provides system administrators with live readings and long-term usage trends for their network devices. The most common usage is bandwidth usage monitoring, but you can also monitor many other aspects of your network like memory and CPU utilizations.