Tier Zero (was Re: Tier 2 - Lease?)

Michael.Dillon at btradianz.com Michael.Dillon at btradianz.com
Fri May 5 13:22:14 UTC 2006

> > On 5/4/06, bmanning at vacation.karoshi.com <bmanning at vacation.
> karoshi.com> wrote:
> > >
> > >         why would anyone do that?

> Hopefully this comes out clearly, as writing can be more confusing
> than speaking...

> My point is it is hard to do anything beyond the first AS# for any SLA
> that you would be paying, since after that the packet switches to no
> money packets on a paid connection, pushing out the issue for things
> sent down that pipe...

Are you saying that there *IS* a good reason why
anyone would buy paid transit from all SFP providers?
And that the reason is so that you have a contractual
SLA with all of those providers?

If so then two questions come to mind. Couldn't you
achieve the same thing by having paid peering with
the SFP providers? Assuming that you do have contractual
service with all of the SFP providers and that there
is an SLA in all of those contracts, how do you deal
with the fact that there is no SLA (to you) on packets
which leave the set of SFP networks? Packets could leave
by going to a transit customer of an SFP network or
by going to a non-SFP peer of an SFP network.

Quite frankly, while terminology like "transit",
"settlement free peering" and "paid peering" are useful
to analyze and talk about network topography, I don't think
they are useful by themselves when making purchase decisions.
They need to be backed up with some hard technical data
about the network in question as well as the contractual
terms (transit or peering) in place.

It is not possible to say that a given network architecture
is BETTER if you only know the transit/peering arrangements
between that network and some subset of the other network
operators. SFP operators will always be a subset of the entire
public Internet. Membership in that set changes from time to
time for various reasons. And the importance of non-members
also varies from time to time, especially content-provider

--Michael Dillon

P.S. I purposely did not use the term "tier" because I
do not believe that current usage of this term refers to
network architecture. It has more to do with market dominance
than anything else and even there it is relative because
there is no longer a single Internet access market.

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