Green Multi-Stage Upgrade for Bundled-Link SDNs with Budget and Delay Constraints
IEEE Transactions on Green Communications and Networking
Upgrading a legacy network to a Software Defined Network in stages, and minimizing the energy consumption of a network are now of great interest to operators. To this end, this paper addresses a novel problem: minimize the energy consumption of a network by upgrading switches over multiple stages subject to the available monetary budget at each stage. Our problem considers (i) bundled links that can be powered-off individually, (ii) decreasing upgrade cost and increasing traffic demands over multiple stages, and (iii) rerouting demands to an alternative path with a delay that is within a predefined limit. Additionally, the link load on the path is no larger than a given maximum utilization. We formulate the problem as an Integer Linear Program and propose a greedy heuristic called Green Multi-Stage Switch Upgrade (GMSU). Experiment results on five actual network topologies show that: (i) our approaches reduce the energy consumption by up to 73.98%, (ii) rerouting traffic demand via longer paths improves the energy saving by up to 9.6%, (iii) GMSU produces results that are at most 4.83% from the optimal result, and (iv) increasing the budget and the number of stages affect the total energy saved and the number of upgraded switches.
Open Access Status
This publication is not available as open access