sFlow, abbreviated from "sampled flow" is an industry standard for packet export which is supported by wide range of network devices in market like Brocade, Dell, Alcatel, Allied Telesis, Cisco Nexus, D-Link, Fortigate, Huawei, HP and many more. NetFlow Analyzer covers your sFlow supported devices to provide real-time details on traffic usage and top talkers in the network. With NetFlow Analyzer you can enable sFlow on each of the interfaces to collect information on traffic usage by interfaces, applications, protocols, IP addresses and QoS.
NetFlow is a protocol for exporting aggregated that captures all traffic, while sFlow is a packet sampling technology where the switch captures every nth packet per interface and forwards it to the collector.
Because sFlow includes the full packet header, it gives you a broader picture of network traffic, providing full layer(L2, L3, L4, and up to L7) visibility into all types of traffic in your network including IP addresses and VLANs, from which you can extract any field. NetFlow essentially contains only a section of those fields.
While NetFlow might give you a lot more information than sFlow, it's resource usage is also a lot more than sFlow, placing a bigger load on your network devices, making sFlow a better choice for lower-end devices. However, which of these protocols suit your network better will depend on what your vendors/networking devices support and your requirements.
Try free edition of sFlow monitoring NetFlow Analyzer at no cost.
Help Guide: How to enable sFlow from a router.