Research On Fault Injection Of COTS-based Safety-Critical Software System

Nowadays, the software system based on COTS component has been used widely, and the reliability of the COTS became more and more important. The high-dependability is essential especially in the fields of safety-critical systems such as aviation, spaceflight and military communication. Once the failure appears in these systems, it may cause the fatal loss of economic, or even military and political affairs. So, for these safety-critical systems, the reliability is a very important parameter. To solve the problems mentioned above, one of the key technologies is the technology of software fault injection, through which we can repeat the software fault quickly, and then provide a basis for fault diagnosis, isolation and recovery. However, this technology is still at the exploratory stage, there are many theoretical and practical problems need to be further studied and resolved.This article focuses on the runtime fault model of the COTS and runtime software implemented fault injection. On the ground of software implemented fault injection technology, we proposed a new model of runtime software implemented fault injection based on fault injection script, and we built the library of runtime fault models of the COTS and designed the script of runtime fault injection of the COTS, giving a new method of encapsulation of the COTS within fault injector. The thesis emphasizes on the fault injection technique of the COTS-based software system, and the injector designed in this thesis can inject faults into the COTS successfully.The result of the experiments proved that this fault injector can inject faults into the target system and show the faults repeatedly. Compare with other kinds of fault injector, this new method of fault injection is more appropriate to the COTS, because this method has the advantage of real-time fault injection, online monitoring and analysis, independent of the source of target system and based-on modifiable fault injection script.