Recently, there has been an interest not only in the topological properties of the networks but also in the interaction between the topology and the traffic that the network carries. For certain regular and symmetric topologies it is possible to relate the onset of traffic congestion to the average shortest paths. In this talk we extend this result to power law topologies (as they describe the internet topolgy) by predicting the onset of traffic congestion using the betweenness centrality of the nodes. This is work in progress, all comments are welcome.