基于链路信息的卫星网络最优路径选择策略

分层卫星网络路由协议在通信时比单层卫星网络有更好的表现,但是同样有着一些缺点。快照的频繁切换导致计算开销大、链路拥塞和节点失效时处理能力较差。针对LEO/MEO卫星网络的特点,提出了一种新的路由协议。计算相邻卫星间的实际通信开销,和预估可选卫星到目的卫星间的通信开销,在保证一定链路利用率和低延时的情况下,选择一条最优路径。当链路切换或节点失效时,缩小路径搜索区域,无需重新计算源卫星节点到目的卫星节点路径,只更新部分失效节点,减少计算开销。通过仿真发现,该算法在路径建立以及链路拥塞等方面具有良好的性能。

An optimized path selecting strategy in satellite network based on satellite link information

Two-layered LEO/MEO satellite networks outperform single-layered satellite networks for their better communication service, however, frequent switching of snapshots leads to large computation cost, poor handling capacity of link congestion and node failure. According to the characteristics of LEO/MEO satellite networks, we propose a routing protocol, which can calculate the actual communication overhead between adjacent satellites, estimate the communication overhead between an optional satellite and the destination satellite, and select an optimal path to ensure certain link utilization and low delay. When the link switch or node failure happens, we narrow the searching area. It therefore becomes unnecessary to recalculate the path from the source node to the destination node, and we can just update part of the failed nodes. Simulation results show that the proposal has good performance in reducing establishing paths and reducing link congestion.