中文摘要：

介绍了软件风险评估的常用方法，并对比各自的优势和不足。针对现有方法不能适应网络化新形势的问题，提出一种基于网络的软件风险模型和评估方法。该方法利用有向网络描述软件风险因素及其相互作用，通过计算风险因素的自然发生概率和传播概率，从系统层面综合考虑多风险因素的共同影响，使风险评估结果更加全面、客观，为该领域研究提供了一种新思路。

英文摘要：

The common methods for software risk evaluation are introduced, and their advantages and shortcomings are also illustrated. To overcome their limitations on risk assessment of networking software, a novel method is pro- posed to estimate software risk. In this method, software risk factors and their interactions are represented as a di- rected graph （network）, in which nodes are risk factors and links denote relationships between these factors; The influences of each risk factor is measured with its natural probability and transport probabilities. So this method makes more comprehensive and objective assessment on software risk, and provides a new way of thinking in this research domain.