Have you tried to visualize your traffic flows? Did you have the problem that your graphs got really cluttered? Did you find a way around that problem? Did you filter data? Did you aggregate multiple nodes into one?
I am sure you have seen graphs that were just horrible to look at. Even worse, it was almost impossible to determine what the graph was trying to communicate. One of the first things you should learn - before you even go ahead and generate a graph - are some simple visualization principles.