[139037] in North American Network Operators' Group
Re: Peering Traffic Volume
daemon@ATHENA.MIT.EDU (Bill Woodcock)
Fri Mar 25 13:45:07 2011
From: Bill Woodcock <woody@pch.net>
In-Reply-To: <AANLkTikOo5zWiuL2_JuSo3PFdt+4uYf83nPhCLY=HLbi@mail.gmail.com>
Date: Fri, 25 Mar 2011 10:44:10 -0700
To: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Mar 24, 2011, at 4:27 PM, Ravi Ramaswamy wrote:
> Hi All - I am new to this mailer. Hopefully my question is posed to =
the
> correct list.
Welcome.
> I am using 2.5 Tbps as the peak volume of peering traffic over all =
peering
> points for a Tier 1 ISP, for some modeling purposes. Is that a =
reasonable
> estimate?
That's actually a very difficult research question for the academic =
community, and one that they've been struggling with since they lost =
their overview of the NSFNET backbone in ~1992.
Ironically, it's quite easy for any one ISP to answer internally, but =
these numbers are closely held as trade-secrets.
One thing you can do is look at the total volume of publicly-reported =
traffic across IXP switch fabrics:
=
https://prefix.pch.net/applications/ixpdir/summary/growth-region/?sort1=3D=
bandwidth&sort2=3D_current&order=3Ddesc=20
=
https://prefix.pch.net/applications/ixpdir/?show_active_only=3D0&sort=3Dtr=
affic&order=3Ddesc
=85where you see about 8.3Tbps of overall reported traffic. Then you =
could do various analyses comparing IXPs where crossconnects are =
prevalent (Equinix Ashburn, say) to ones where they are not, and looking =
at which ISPs peer at each. You could also try to find out from ISPs =
which IXPs they use crossconnects at, and which they don't. That may be =
easier information for you to get than how much traffic they're doing =
individually.
It might also be interesting to look at some of the IXPs that publish =
per-participant traffic figures, to see if you can develop =
characteristic statistical distributions for =
amount-each-participant-contributes-to-the-IXP, though you should be =
cautioned that the curve might be much heavier-tailed for a large =
exchange than a small one.
Ultimately, if you're considering this as an academic research question, =
you may want to think about the utility of examining a "black box" =
question like this, when the answer is plainly known to other people, =
just not known to, or verifiable by, you. The chances of getting the =
answer "right" are low, and if you do get it "right" neither you nor =
your thesis advisor would ever find that out. There are many other =
classes of problem that are potentially much more rewarding, because =
they would contribute to our overall knowledge of how the network works: =
BGP route convergence and stability properties in chaotic (i.e. =
real-world) networks; documenting the performance and economic effects =
(and the tradeoff with stability) of denser peering meshes; study of the =
uptake of DNSSEC; study of the prevalence of different IPv4/IPv6 =
transition technologies...
-Bill
