卫星网络需要采用一些安全机制来保证其数据传输的可靠性，而现有的信任评估模型难以满足卫星网络的一些内在特征需求．有鉴于此，文中结合Dempster-Shafer( D-S) 证据理论，提出一个基于卫星节点的节点信任评估模型，通过该模型可以得到卫星节点间的直接信任和间接信任的信任值．文中还提出了一个可信的按需卫星路由( T-ODSR) 协议，该协议能够根据卫星节点的信任值选择可信的路由进行数据传输．实验结果表明，相比传统的双层按需卫星路由( ODSR) 协议，T-ODSR 协议能够有效地抵御攻击，提高网络的可靠性、健壮性以及安全性，特别是当卫星网络中存在较多恶意节点时优势更为明显．

In satellite networks,security mechanisms are required to ensure the reliability of data transmission. However,the existing trusted evaluation models can not meet the requirements of inherent characteristics of satellite networks. In order to solve this problem,a trusted evaluation model based on satellite nodes is proposed with the help of the D-S evidence theory,through which the trustworthiness of direct trust and indirect trust of satellite nodes can be easily obtained. Moreover,a trusted on-demand satellite routing ( T-ODSR) protocol is proposed,which can select trusted routes to transmit data according to the trustworthiness of satellite nodes. Experimental results indicate that,as compared with the classical double-layer on-demand satellite routing ( ODSR) protocol,T-ODSR protocol is more effective in resisting network attacks and improving network reliability,robustness and security,especially in the presence of a large number of hostile nodes.