Path Consolidation for Dynamic Right-Sizing of Data Center Networks

Data center topologies typically consist of multirooted trees with many equal-cost paths between a given pair of hosts. Existing power optimization techniques do not utilize this property of data center networks for power proportionality. In this paper, we exploit this opportunity and show that significant energy savings can be achieved via path consolidation in the network. We present an offline formulation for the flow assignment in a data center network and develop an online algorithm by path consolidation for dynamic right-sizing of the network to save energy. To validate our algorithm, we build a flow level simulator for a data center network. Our simulation on flow traces generated from MapReduce workload shows 80% reduction in network energy consumption in data center networks and ~25% more energy savings compared to the existing techniques for saving energy in data center networks.