We’ve blogged about the differences between NetFlow and sFlow before but this debate continues to come up often enough and has been going on long enough that it needs to be put to rest once and for all. So let’s cut right to the chase:
JFlow is a IP traffic flow sampler technology used by Juniper manufactured routers and switches. JFlow is considered a flow sampler technology much like Sflow, and when enabled on an interface; it allows packets in the input stream to be sampled. As the packets flow through an input stream the router/switch will look at each one, but only records new packets and discards any packets it has already seen.
JFlow is just one of three flow technologies available; among the 3 include Cisco’s Netflow and HP’s Sflow technologies. Each having their own strengths; Netflow records all packets while SFlow will only sample incoming traffic based on the packet ratio defined in the router configuration.