Developed by Cisco, NetFlow (along with its open-source cousins sFlow, IPFIX, and J-Flow) allows routers and switches to export metadata about traffic flows. But many admins assume that "NetFlow" means "Expensive SolarWinds license."
Before diving into the tools, let’s quickly define the technology. Originally developed by Cisco, is a feature that collects IP traffic information as it enters or exits an interface. netflow monitoring free