Alternative to NetFlow for Measuring Traffic flows

Richard A Steenbergen ras at
Tue Dec 17 03:07:10 UTC 2002

On Mon, Dec 16, 2002 at 05:46:10PM -0800, William B. Norton wrote:
> 1) You adjust routing to prefer one transit provider or the other for the AS
> 2) Shift traffic to the particular AS from one transit provider to the 
> other, noting the change in the loads on the transit providers.

Ouch. Among other problems, you really have no idea what is peak time for 
that peer, which may be very different from your overall peak time.

Is there some reason you don't have netflow available, or are you just 
trying to work around the known problems of it, such as not being able to 
get a true reading due to best path issues?

I am quite happy with my method, using netflow export projected against an 
external routing table. It gives pretty accurate results, *IF* you have 
the correct external routing table. For two potential peers this is easy 
to get, but for other use it is sometimes fairly difficult to get accurate 
and current table of someone's customer routes. Unfortunately it seems 
many people view this as "NDAable information", and won't make it 
accessable via a route-views type service.

Richard A Steenbergen <ras at>
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)

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