Abstract: In order to analyze the influence of applying design patterns to software safety in software design, this paper carries out a case study on bridge pattern with Software Fault Tree Analysis(SFTA). The result shows that the application of bridge pattern makes the safety reduce by 50%, but the software modules can be decoupled and redundancy design can be added. Introducing double redundancy can improve software safety by two orders of magnitude. The conclusion is valuable for object-oriented design of safety-critical software.

Key words: Software Fault Tree Analysis(SFTA), design pattern, software safety

摘要：

采用软件故障树分析法，通过一个应用桥接模式的实例研究在软件设计中引入设计模式对软件安全性的影响。结果表明，单纯引入桥接模式，软件的安全性约降低50%，但引入设计模式使得软件模块之间解耦合，通过加入双余量设计，可以使软件安全性提高2个数量级。该结论对安全关键软件面向对象的设计具有指导作用。

关键词: 软件故障树分析, 设计模式, 软件安全性

CLC Number: 

• N945