星座网络关键链路代价增量路由算法

摘要

The problem of low resource utilization of satellite networks is getting worse, due to huge and uneven distributed global communication traffic. To solve this problem, a critical links routing algorithm (CLRA) for satellite constellation networks was proposed. Based on the statistical distribution model, the candidate paths were chosen by propagation delay and current link load status. The concept of critical link was introduced and a prediction model of their incremental cost established. Finally, the optimum routings were selected based on minimum incremental costs. A congestion control strategy was adopted to discover and reduce the traffic of the overloaded links, and then reassign the parts of the routings. Experimental results clearly demonstrate that CLRA greatly improves the average route blocking probability, throughput rate, path delay and load balance. While satisfying the premise of the delay requirement, CLRA can also allocate networksresource efficiently and improve resource utilization, which is very suitable for satellite networks.%全球通信业务量大且分布不均衡的客观因素,使得卫星网络资源利用率较低的问题日趋严重.为了解决这个问题,提出了一种面向星座网络的关键链路路由算法.该算法在业务统计模型下,以传播时延和当前链路负载状态为链路代价选出候选路径.在此基础上引入关键链路的概念并建立关键链路代价增量预测模型,最终从候选路径中选择代价增量最小的为最优路由.算法还采用拥塞控制策略发现拥塞,减轻拥塞链路的负载,选择重新设计部分业务的路由.实验结果表明,算法在平均路径阻塞概率、吞吐率、路径时延以及负载均衡方面均有较好的提升；在满足时延要求的前提下,能够有效地分配网络资源,提高网络利用率,是一种较好的卫星网络路由算法.