卫星网络是一种特殊的时变网络,其QoS路由问题比地面网络QoS路由问题更为复杂.本文利用卫星拓扑的可预测性,通过引入业务的中断概率和费用模型来描述链路切换对业务QoS以及网络的影响,并给出时延受限最小费用路由(SDCMCR)算法来解决在卫星链路时延长的情况下寻找满足时延限制条件且受切换影响最小的路径的问题,该算法可兼顾网络业务中断率和业务阻塞率等性能,且计算复杂度低,可适应星上设备处理能力的要求.仿真表明算法在计算复杂性、业务请求被阻塞的概率等方面都优于同类算法.
Mobile satellite network is a special time - varying network, and its QoS Routing problem is more complicated than the QoS Routing problem of current terrestrial networks. By exploiting the predictive nature of the mobile satellite topology and introducing the interrupting probability and the cost model of service, the influence on the QoS and network performance caused by the handover is described. Besides, a novel satellite network delay constraint minimum cost routing (SDCMCR) algorithm, which can obtain a path to satisfy the delay constraint as well as the minimization of influence caused by the handover,is proposed. This algorithm gives attention to the network performance of service interrupting and blocking. And at the same time, it has a low computing complexity to adapt to the restricted computing capability of satellite equipment. Correlative simulation indicates that this novel algorithm is superior to other current algorithm in respect of computing complexity, service blocking probability etc.