Design And Implementation Of A Bytecode-based Software Monitoring And Trusted Evolution Framework

With the continuous development of the Internet, and as the size and complexity of the software system rise, the fault and failure of software become more and more serious, which brings great impacts on our lives and even the national security. Consequently, how to construct dependable software for the purpose of ensuring it runs safely and reliably under the dynamic and open environment has drawn wide attentions. The essential characteristic of dependable software is the behaviors of the software are consistent with users'expectations. Getting software run-time status information through the effective monitoring over the software, and making real-time examination and analysis of the status information, then adjusting the software systems by dynamic evolution techniques, this method can effectively improve the dependability of the software system. However, the current monitoring and evolution technology is still in the early developing stage, and there are still many technical and practical limitations, such as the capability for describing monitoring requirements is not flexible, monitoring information check logic and business logic of the target system are entangled, it lacks of lightweight monitoring mechanism for non-source-code system and the universal and automation of platform and tools which support monitoring and evolution are not enough.With respect to these issues, this paper proposes a bytecode-based software monitoring and trusted evolution framework model (BSMEF). Based on the bytecode-based AOP techniques, the model automate infuses the monitoring requirements as crosscutting concerns into the business logic byte-code files of the target software system, it collects the monitoring information of software system, such as the runtime status and runtime environment information, and makes real-time examination and analysis. Matching the analyzed results with the evolution rules, when the rules are triggered, the model provides dynamic evolution capability through class loader and reflection mechanism, which can be used for real-time intervention to the software system.The content of this paper can be generalized as follows:1. Proposing a bytecode-based software monitoring and trusted evolution model, BSMEF. It consists of Business-logic and Monitor-requirement Description Module, Monitoring Capability Infusing Module and Online Evolution Module. The model is possessed with loose coupling, function independent, irrespective of specific applications, and certain universal and scalability, which is a platform-independent lightweight extensible framework.2. Designing and implementing a bytecode-based software monitoring and trusted evolution framework (BSMEF) based on the proposed model. BSMEF allows software developers using the monitoring programming language to express monitoring requirements independently. Based on byte-code oriented AOP techniques, this paper implements the automate infusing mechanism and the run-time evolution capability based on monitoring information.3. This paper points to the load balance of distributed file transfer system; it has implemented the monitoring capability infusing and the online evolution, in order to validate the BSMEF framework. Results show that the framework is availability and accuracy on the monitoring capability automation infusing and the capability of online evolution for non-source-code systems. Meanwhile, this paper has validated that the byte-code monitoring capability infusing method has improved the efficiency than the source-code based monitoring capability infusing method through quantitative analysis and comparison.