routing around Sprint's depeering damage
George William Herbert
gherbert at retro.com
Mon Nov 3 16:26:28 CST 2008
>On Nov 3, 2008, at 9:41 AM, HRH Sven Olaf Prinz von CyberBunker-
>Kamphuis MP wrote:
>>> No, but the providers who provide those connections should be
>>> If they're not, I'd consider switching providers. Simple as that.
>> multihomed to whichever parties decide to generate split ups on
>> in the intarrwebbz.. meaning: all of them.. (you can never tell
>> which ones
>> will get the idea to depeer next, so you have to be multihomed to
>> all of
>> them or this can still happen)
>I am afraid you are confused. No, you do not have to attach to every
>network unless you think every network is going to disconnect from
>every other network simultaneously. (Would there even be an Internet
>If you are attached to two transit-free networks, you are guaranteed
>connectivity to the entire Internet unless there is more than one
>bifurcation simultaneously. And not just any two bifurcations.
>Specifically, both of your upstreams would have to depeer the same
>transit free network at the same time.
>Attach to three, and it would require all 3 to depeer someone
>simultaneously to affect you.
Look at this from the connectivity reliability point of view.
With a technical failure, people will start rushing around to
get it fixed, and NOCs will cooperate to provide ways around
things that are down. Even for major fiber cuts, we see rapid
restoration and low downtime. It seems to take major router or
management software glitches to have large segments of the net
down for all day.
MTTR of a depeering is days or weeks. And it's not the sort of thing
that people will cooperate to fix.
Even worse - eventually we're going to have a legit outage on top
of a depeering event, which will ruin a lot of people's days.
When this gaming was active (depeering) in the 90s, I walked a couple
of million dollars a year in connectivity away from one of the major
offenders because my customers had to be able to get to me. I didn't
really care what their business justification was - I was paying them
for people to be able to reach me, and they couldn't do that.
I have had a number of years of primarily being worried about
software failures and diverse fiber being groomed behind my back.
If depeering is again to be a major cause of outage time, in terms
of customer seeing site down time per year, then I need to recalculate
all my provider relationships again. Providers who are willing to
play depeering games will be assessed a higher estimated outage time
per year in my cost/benefits tradeoffs. They will either have to
adjust costs appropriately or I will start walking sites again.
Sprint isn't currently my direct provider anywhere, but they won't
get a chance to become it again anywhere unless either they agree
to stop playing peering games, or can lower prices to be competitive
with networks with equivalent outage risks. I will not pay a premium
cost for inferior ultimate reliability.
-george william herbert
gherbert at retro.com
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