Improving fairness of OBS routing protocols in multimode fiber networks

Multimode fiber networks are emerging as one of the most promising technologies to meet the ever-increasing bandwidth demands of network users. In this paper, we propose and evaluate two new schemes for alleviating the fairness problem in optical burst switching networks that use mode-division multiplexing as well as wavelength-division multiplexing. To our knowledge, this is the first research work on solving the fairness problem in multimode fiber networks. The two schemes use formulas that adjust the size of the search space for a free mode or a free wavelength based on the distance of the current hop of the burst from the source node. Additionally the second scheme uses a formula to adjust the size of the search based on the size of the burst, thereby attaining higher throughput without sacrificing hop count fairness. Extensive performance tests are presented to evaluate the two schemes and analyze their effectiveness in improving fairness either without negatively impacting network throughput or with an improved throughput for the second scheme.