Adaptive burst reordering for burst-cluster transmission to improve fairness in OBS networks

摘要

Hop-based burst-cluster transmission has been proposed to improve fairness in optical burst switching networks, and a burst-cluster is generated from multiple bursts. By arranging bursts from the smallest number of hops to the largest one, the burst loss probability for a small (large) number of hops increases (decreases), improving fairness. However, depending on the amount of traffic on each link, the burst loss probability for a small number of hops becomes larger than that for a large number of hops for some source nodes. Therefore, all source nodes can not always improve fairness. In this paper, an adaptive burst reordering algorithm for the hop-based burst-cluster transmission is proposed. Here, each source node calculates the burst loss probability for each number of hops from the number of received ACK and NACK messages. Next, the source node changes the order of bursts within a burst-cluster dynamically. The performance of the proposed method has been evaluated in tandem networks and mesh networks such as NSFNET and ARPA2 by simulation. Numerical examples show that the proposed method is effective for improving the local fairness for each source node regardless of the amount of traffic on each link.