>>This is not my question. My question is there a way to detect problem after the fact or not.
>
>You may try to get in touch with major providers in US and Canada and try to obtain info from them, as well as sharing points on backbones and things like that. But, even when I tried, this is so confidential that I can't barely get some info. When things like that happen, to what I am assuming, this is very high level with top engineered departments and those people are not reachable from the public, usually.

I think we're not understanding each other. My question was completely different. My question was are you able to determine after the fact based on the log analysis if UT was not accessible or not in a particular time frame. I was not asking if you can fix the problem or not.