Abstract: Software reliability is usually estimated with reliability models, but most of theories on software reliability are evolved from the hardware, which may not reflect the feature of software appropriately. For this reason, a software reliability estimate method based on function-path is presented by the fault origin of software. The connection between software reliability and the amount of fault-path is built by the concept of function-path, and then the connection to input space is also built by the concept of operation. The paper analyses the relation between time and software reliability, and proposes the method of the model in practice. Finally, the result of the experiment indicates that the method possesses reasonableness and feasibility. The method can be used for reliability validation in the usage phase.

Key words: software reliability, function-path, operation, input space, running status

摘要： 软件可靠性一般是通过可靠性模型进行估计，而软件可靠性理论大都从硬件产品发展而来，不能恰当地反映出软件产品的固有特点。基于这样的考虑，从软件故障产生的根源出发，提出一种基于功能路径的软件可靠性评估方法。通过功能路径的概念，将软件可靠度归结到故障路径的数目上，再通过操作的概念与输入空间建立联系。分析了时间因素与软件可靠性的关系，并给出了该模型在实际测试中的估计方法。用实例分析验证了该方法的可行性。这种评估方法可用于软件使用阶段的可靠性验证。

关键词: 软件可靠性, 功能路径, 操作, 输入空间, 运行状态