Questions


Locate: Where does a path failure manifest itself?
With respect to end hosts? 
What types of links? (intra-AS, etc.)
How can we observe this from the edge?
(Traceroute is not good enough!)

Characterize: Do failures elicit specific qualities?
Does failure occurrence depend on location?
Does failure duration depend on location?

Correlate: Do failures correlate with routing instability?
If so, under what circumstances?