QoS routing algorithm based on traffic classification in LEO satellite networks

Low Earth Orbit (LEO) satellite networks are expected to provide a variety of multimedia applications. In order to satisfy different QoS requirements and optimize utilization of network resources, a novel traffic classification routing algorithm (TCR) is proposed. The key technique of TCR is investigating the traffic classification link-cost metrics (TCM) for different traffic classes, which selects the next-hop based on real time link state information. Furthermore, in order to improve TCR's performance and balance the entire traffic load distribution, two novel mechanisms are developed: a blocking-probability filter mechanism and a server reservation priority queue (SRPQ) mechanism. The performance of TCR is evaluated in different traffic scenarios using a discrete-time traffic and topology (DT-TT) model. It is compared to both the single-service routing algorithm and the multiservice routing algorithm. The advantages of the proposed scheme, in terms of average path delay and blocking probability, are corroborated by ample simulations, where significant gains in performance are achieved.