LEO卫星星座系统组播报文扩散算法

Link Load Based Multicast Packet Diffusion Algorithm in the LEO Satellite Constellation System

为了解决星际链路子网出现重负载时组播报文扩散问题,提出了LEO卫星星座系统组播报文扩散算法.依据每个卫星节点的流量分布,采用基于链路负载的广度优先树算法,生成到目标节点路径最短的广度优先树和扩散转发表.组播报文依此能够避开拥塞链路和节点,以最佳路径快速扩散到各个卫星节点,且不会出现环路.仿真结果表明,当网络重负载时,采用本算法,其组播报文扩散时间与网络轻负载时大致相同,且报文不会丢失,满足组播报文扩散时延最短且无环路的要求.

To solve the diffusion of multicast packets in the Inter-satellite Link（ISL） subnet with a heavy load,a multicast packet diffusion algorithm in the LEO satellite constellation system is presented.Based on the traffic distribution of each satellite node,the link load based breadth first tree algorithm is used to form the breadth first tree and the diffusion forwarding tables with the shortest paths to the target nodes.With these tables,the multicast packets can avoid the congested links and nodes,and can be diffused to each satellite node rapidly along the optimal loop-free route.The simulation results show that,with this algorithm,the diffusion time of multicast packets in the network under a heavy load is almost the same as that under a light load,and the packets are never lost.It can meet the shortest diffusion time of multicast packets and loop-free multicast routes requirements.