See the 1990 ATT long-distance collapse for a worked example.
I won't believe a company like Level3 would not deploy backplane
protection/policing on routers. Also, 1Tb/s aggregated DDoS towards OVH
network didn't pause or rebooted routers. And i guess both companies have
had their share of (D)DoS in the past, so they had the time to get up to
the challenge. Now... there where times where one malformed IP packet would
cause a memory leak leading to a router reboot... :)
... but back then they didn't have ITIL and the likes (at least not that i
knew... but then again, i was just starting with networking back then),
where a ChM process must produce risk, impact, etc, reports, and at least
one peer review meeting for approval 
Just so. We are just speculating, but in light of recent GRE attack developments, the ddos possibility is worth considering.
-mel beckman
Well, Level3 has by no means said that this was the result of a DDoS, that's just speculation on behalf of folks who do not work at Level3 so far.
I won't believe a company like Level3 would not deploy backplane
protection/policing on routers. Also, 1Tb/s aggregated DDoS towards OVH
network didn't pause or rebooted routers. And i guess both companies have
had their share of (D)DoS in the past, so they had the time to get up to
the challenge. Now... there where times where one malformed IP packet would
cause a memory leak leading to a router reboot... :)?
Yeap, i know, it was what i understood, as it is my opinion that a zero day
would fit better... in the pure speculation world
At the end of the day... maybe some undocumented fault int some obscure
functionality that was activated/deployed a long time ago, and just
revealed it self now... There are so many things that can go wrong on
complex networks even with all the controls imposed on changes...
Possibly somebody YANGed when they should have yinged
-mel beckman
Yeap, i know, it was what i understood, as it is my opinion that a zero day would fit better... in the pure speculation world
At the end of the day... maybe some undocumented fault int some obscure functionality that was activated/deployed a long time ago, and just revealed it self now... There are so many things that can go wrong on complex networks even with all the controls imposed on changes...
Well, Level3 has by no means said that this was the result of a DDoS, that's just speculation on behalf of folks who do not work at Level3 so far.
I won't believe a company like Level3 would not deploy backplane
protection/policing on routers. Also, 1Tb/s aggregated DDoS towards OVH
network didn't pause or rebooted routers. And i guess both companies have
had their share of (D)DoS in the past, so they had the time to get up to
the challenge. Now... there where times where one malformed IP packet would
cause a memory leak leading to a router reboot... :)?
Looks like a fat finger event...
From Level 3:
"On October 4, our voice network experienced a service disruption affecting some of our customers in North America due to a configuration error. We know how important these services are to our customers. As an organization, we're putting processes in place to prevent issues like this from recurring in the future. We were able to restore all services by 9:31am Mountain time."
It’s good to see them acknowledging this.
-mel
Can anyone who was affected by last week's outage confirm that 911
services were impacted (I assume they were)?
Anyone know if the current outage is in any way related to this one from
last week?
http://downdetector.com/status/level3/map/