A New Backup Topology Design Method for Congestion Avoidance in IP Fast Reroute
Simon Tembo, Ken-ichi Yukimatsu, Ryota Takahashi, Shoei Kamamura, Tatsuo Miyamura, Kohei Shiomoto · International Journal of Networks and Communications · 2012
We present a backup topology design method to avoid congestion in IP Fast Reroute. IP Fast Reroute techniques prepare backup topologies used to determine backup routes after a network failure. However, using more backup topologies consumes a lot of network resources. Reducing the number of backup topologies is a problem, as some links becomes overloaded. In this paper, we present a backup topology design method that splits the traffic on high load links to other links by considering network conditions, such as the traffic matrix or topology. The main idea of our method is the introduction of a concept called a Special Node, which is a node with a higher node degree, in the backup topology. We quantitatively illustrate the effectiveness of our method in terms of maximum link load reduction. The results show that, with the same number of backup topologies as the conventional method, our method can reduce congestion by 75%. It is effective for various topology models and not dependent to the network size. In this paper, we demonstrate that by selecting about 20% of the nodes as Special Nodes is very effective, particularly in large networks selecting Special Nodes whilst considering node position gives maximum effect. In this paper, we present that using our approach of selecting Special Nodes in the backup topology and then maximize the number of available links to the Special Nodes we can avoid congestion in IP Fast Reroute.