sFlow is a technology for monitoring traffic in data networks containing switches and routers.
The sFlow monitoring system consists of an sFlow Agent (embedded in a switch or router or in a standalone probe) and a central sFlow Collector.
The sFlow Agent uses sampling technology to capture traffic statistics from the device it is monitoring. sFlow Datagrams are used to immediately forward the sampled traffic statistics to an sFlow Collector for analysis.
An sFlow Collector receives sFlow Datagrams from one or more sFlow Agents.
The current version is 5. It has superceded RFC 3176 that describes v.4