Model analysis of dynamic priority segmented burstification and deflection routing

摘要

Heterogeneous data traffic is increasingly becoming a complex mix of both delay tolerant and intolerant IP traffic. Optical Burst Switched (OBS) networks have since become a backbone network solution to handle the resultant zetabyte volumes of such traffic concurrently using the burst assembly and transmission approach. The strict minimum burst size constraint requirements as well as varying maximum delay bounds for most traffic types makes it difficult to render an acceptable and consistent quality of service (QoS) for the aggregated traffic in such networks Hence in this paper we propose a dual priority with jump priority segmented burst assembling coupled with a most efficient route (MER) selection when deflection contending bursts in the network interior. At the egress nodes, newly arriving low priority (LP) data segments may under certain conditions, jump to the high priority (HP) queue. In that way the delays are minimized and this leading to improvement in overall renderable QoS. We provide a queuing model analysis of this model as well as the QoS metrics. In the core network, taking into cognizance that deflection routing based contention control can exasperate/accelerate congestion, we propose that the most efficient route (MER) be chosen for deflecting the contending burst, as this will reduce congestion on loaded routes. Analytical as well as simulation results show that dual priority burst segmentation with jump priority approach, coupled with MER deflection routing can improve on QoS metrics while at the same time utilizing the available network resources rationally and efficiently under moderate to high network traffic conditions.