Cisco gives you the sensor (NetFlow) for free inside every router you already own. Pair that sensor with a free analyzer, and you stop being the network admin who says, "The network looks fine from here," and become the hero who says, "The marketing department’s automated Dropbox sync is saturating the link. I’ll throttle it in five minutes."

In this article, we'll review some of the best free NetFlow analyzers for Cisco that can help you optimize your network performance and security.

SolarWinds NetFlow Traffic Analyzer is a free tool that allows you to monitor and analyze NetFlow data from your Cisco devices. The tool provides detailed traffic analysis, including top talkers, protocol breakdown, and packet size distribution. It also supports multiple NetFlow versions, including NetFlow v5, v7, v9, and IPFIX.