Evaluating differentiated quality of service parameters in optical packet switching

Optical packet switching (OPS) is a promising technology for future generation networks solutions. One of the great challenges to be addressed is differentiated quality of service (QoS) and a major concern in providing QoS is packet loss. In case of differentiated services, packet losses should be significantly less likely for high priority classes than for low priority classes. However, as packet losses are very unlikely they become rare events which poses serious challenges to conventional analysis methodologies. We present an importance sampling scheme for fast simulation of packet loss rates in this setting. The change of measure adapts according to ant colony optimization, a metaheuristic inspired by the foraging behavior of ants. Thereby, our simulation does not require intimate a priori knowledge of the system and overcomes a general drawback of importance sampling. Within very moderate simulation time, accurate results are provided for an OPS model with varying parameter settings.