ABSTRACT
Research on trusted software is one of the branches of trusted computing. Software system is playing an increasingly important role in the information society. An error operation of software may result in economic damage and in the extreme cases cause deaths. When lives and fortunes depend on software, assurance of its quality becomes an issue of critical concern. At present, trusted degree is one of the key metrics for measuring the quality of software system. However, how to integrate the software trustworthiness into software design[7] and how to get the trusted degree as accurate as possible is still a problem in the field of trusted computing.
