Checking if the implementations conform to the requirement models is challenging. Most existing techniques for consistency checking either focus on requirement models(e.g., requirements consistency checking), or on the implementations(e.g., code-based testing) only. In this paper we propose an approach to checking behavioral consistency of implementations against requirement models directly to overcome these limitations. Our approach extracts two behavioral models represented by Labelled Transition Systems(LTS) from requirement models and implementations respectively, and checks the behavioral consistency between these two models based on behavioral simulation relation of LTS. The checking results of our approach provide evidence for behavioral inconsistency as well as inconsistent localization. A research prototype called BCCH and a case study are presented to give initial validation of this approach.
To check whether a program behaves in expectation, program monitoring systems are used for intrusion detection. This article presents a program monitoring system using automaton simulation based on the state graphs extracted from C programs through static analysis. For complete state graph construction, a pointer alias analysis method is proposed to solve the function pointers for obtaining actual control flows. After compiling, programs are instrumented with probes to report the internal states when they are running. A program monitor is built in the kernel of Linux system, which monitors the states of programs from probes and checks the paths of execution. This monitoring system could respond to the abnormal behaviors immediately to protect the systems and programs from further damages.
