[90146] in North American Network Operators' Group
Re: Tier 2 - Lease?
daemon@ATHENA.MIT.EDU (Valdis.Kletnieks@vt.edu)
Wed May 3 02:16:29 2006
To: rob@robsherrard.com
Cc: nanog list <nanog@merit.edu>
In-Reply-To: Your message of "Tue, 02 May 2006 22:38:22 PDT."
<445841CE.8090701@robsherrard.com>
From: Valdis.Kletnieks@vt.edu
Date: Wed, 03 May 2006 02:16:00 -0400
Errors-To: owner-nanog@merit.edu
--==_Exmh_1146636960_2530P
Content-Type: text/plain; charset=us-ascii
On Tue, 02 May 2006 22:38:22 PDT, Robert Sherrard said:
> What make a provider a tier 2, versus a tier 1 provider...
Usually it's defined as "Tier 1's don't buy transit, Tier 2's do". Of course,
it gets a lot more complicated, because you can easily have a "Tier2" that's
peering for 95% of its prefixes, and buying transit for 5% of not-often-used
prefixes simply because it's expensive to get a peer for that 5%. But said
Tier2 may be bigger than some "tier 1s", and be better on any *rational*
comparison criteria (price, support, throughput, latency, jitter, downtime/SLA,
path diversity, etc....)
If a company is "almost a Tier1", but buys transit for several hundred prefixes
coming from Korea and Nigeria (say, 0.2% out of the 180K or whatever the
routing table is this week), why do you *care*, unless you have (or *seriously*
plan to have) lots of packets coming and going to those 2 countries?
In general, the people who *really* care about Tier 1/2 already know if they
are a 1 or a 2 themselves. Almost everybody else falls into 2 categories:
1) People who are using 1/2 as a shortcut for doing a *proper* analysis of the options.
2) People who feel a marketing need to say "we peer with X Tier-1s".
(OK, where's my asbestos long-johns? ;)
> Is it possible to determine who a tier 2 (i.e. Cogent) leases fiber from?
Try asking? :) (And the answer will probably depend on which exact leg of their
network you're asking about - it's almost certainly a patchwork....)
It probably doesn't matter unless you're trying to buy connectivity over
diverse paths - in which case you're going to have to ask *both* providers
what the exact fiber routing is. It's possible the tier2 and the tier1 are
both leasing previously-dark fiber in the same conduit - but leasing it from
2 different companies.
And of course, it's quite possible that *this* week, that tier 2 is routing
your packets over fiber they own, and next week, some traffic engineering puts
your packets on fiber leased from A - and last week, it was on fiber leased from B.
(Disclaimer: we're neither a Tier 1 or 2. And most of the routes we receive via
a regional provider that treats us *very* nicely - mostly because we have them
by the short-and-curlies. They piss us off too much, we turn off the phones in
their NOC. ;)
--==_Exmh_1146636960_2530P
Content-Type: application/pgp-signature
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.3 (GNU/Linux)
Comment: Exmh version 2.5 07/13/2001
iD8DBQFEWEqgcC3lWbTT17ARAtpzAKCuZdUrqoBAX0FNj/tZsmLlWKp5jACg5oIg
pKqmyNzpPN3ra0CHtQZtPPU=
=l7su
-----END PGP SIGNATURE-----
--==_Exmh_1146636960_2530P--
