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Re: Real world sflow vs netflow?


From: Joe Loiacono <jloiacon () csc com>
Date: Fri, 13 Jul 2012 21:30:37 -0400

Peter Phaal <peter.phaal () gmail com> wrote on 07/13/2012 04:20:45 PM:

2. sFlow: Packets are randomly sampled in hardware and the packet
headers are immediately exported as sFlow datagrams - there is no flow
cache on the switch/router. In addition to exporting the packet
header, the sFlow agent captures the FIB state associated with
forwarding the sampled packet, exporting information such as next hop
router, AS-path, communities etc

What about byte counts? Just those in the sampled packet (i.e., no running
totals per flow)?

In contrast, the sFlow standard specifies how sampling must be performed
and ensures that information is included that allows the sampled data
to be correctly scaled and produce unbiased measurements.

Does sflow software typically recreate the total byte count per flow (e.g.,
TCP session) by scaling?

Thanks,

Joe



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