构件化嵌入式软件可靠性预测模型

Reliability prediction model of component-based embedded software

由于传统的基于黑盒的可靠性建模方法不适合构件化软件开发,所以如何利用软构件的可靠性,预测分析嵌入式系统的可靠性成为一个亟待解决的问题.考虑到构件开发者与使用者相分离的特征以及构件化软件的组装方式,综合应用构件可靠度属性、用户使用剖面以及系统架构,建立了一个构件化软件可靠度分析预测模型.此模型的核心思想包括:软件的架构建模为离散马尔科夫状态机模型,将并行、冗余、调用等复杂结构通过视图映射转换为状态机模型;构件的开发者给出构件每个接口的可靠性,构件应用者按构件级、接口级两个层次给出构件的使用剖面,据此可计算出构件在不同应用场景的可靠度.

Traditional software reliability growth models based on the black-box approach are inappropriate to model the reliability of component-based software. How to analyze and predict software reliability from components＇ reliabilities is concerned. Considering that the component developer and user may be different and taking into accomlt the assembling methods of component-based software, a reliability prediction model of component-based embedded software is proposed. Using this model, the reliability of the system is a function of the stochastic properties of the component failure behavior, the architecture structure of the program and the utilization of these components by the user. The main ideas of this model are： firstly, the software architecture is modeled as a discrete time Markov chain, and complex structures such as parallel, redundant and subroutine calls are transformed from the architecture view to the state view, secondly, the developer of the component gives each interface＇s reliability of the component and the user provides the usage profile from the component level and interface level, on the basis of which we can calculate the eomponent＇s reliability in different use scenarios.