中文摘要：

针对已有简化网格服务可靠性模型无法精确反映网格网状拓扑结构特性的问题，提出了一种把已有简化网格服务可靠性模型扩展为网状拓扑结构的网状结构网格服务可靠性模型。同时，基于网状结构服务可靠性模型，提出了一种适用于网状结构服务可靠性模型的服务可靠性评估算法，该算法通过形式化描述模型以及化简求解获得网格服务的可靠性分布。实验表明，网状结构服务可靠性模型以及可靠性评估算法不仅兼容已有简化网格服务可靠性模型，而且适用于复杂网状结构网格系统建模。

英文摘要：

To address the problem that the existing simplified reliability models for grid services can not reflect the characteristic of network-structured topology of grid services, a network-structured reliability model that extends the topologies of the existing simplified reliability models to the network-structured topology is proposed, and based on the network-structured reliability model, an algorithm for evaluating the grid service reliability distribution is presented. The algorithm obtains the reliability distribution of grid services based on formalized specification and simplified solving procedures. The experimental results show that the network-structured reliability model and the algorithm for evaluating the grid service reliability distribution can not only be compatible with the existing simplified service models, but also be adapted to the complex network-structured topology of grid.