sFlow vs netFlow/IPFIX

Saku Ytti saku at ytti.fi
Mon Feb 29 12:41:03 UTC 2016


On 29 February 2016 at 14:17,  <sthaug at nethelp.no> wrote:

> A relevant question might be if the Trio hardware can do 1:1 while
> handling multiple ports of line rate DDoS traffic consisting of small
> packets with different port numbers (i.e. high pps traffic resulting
> in basically 1 flow per packet). No, I don't know the answer (but I
> suspect it might be negative).

I cannot see why not, it's cheap. You're doing 1-2 LPM on the packet,
QoS lookup, ACL lookup, incrementing various counters, etc., adding
one hash lookup and two counters is not going to be relevant cost to
the lookup time.

Having many entries in the hash table is an issue, incrementing their
counters is not.

> Here we're using Trio hardware with 1:100 sampling, and are reasonably
> happy with the results.

-- 
  ++ytti



More information about the NANOG mailing list