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Massimo Candela
Hello Ken, A static path is a path that doesn’t change the set and the order of the traversed ASes during the whole time interval. This means that it can appear and disappear (e.g. if an ISP has a fault) indefinitely as long as the route is the same. They are not necessarily red, they are divided in different colored trees in a way that for each path on each tree you will always know the exact route without ambiguities.