Initial Study On Software Trusted Measure

Trusted Computing is one of the hottest topics in the information security field. Whether the computer system is trusted, is based on whether hardware, network, operating system, middleware, application software, users of information system and the complicated systems between them were trusted. The computer system will be not trusted if problem appeared in any of these links.Current research on trusted computing domestic and overseas is focus on hardware level. Research on trusted software is one of the branches of trusted computing. For application software which became more and more complicated, it's a problem that there were errors, failures, limitations inside the software and virus, malicious codes outside it. How to evaluate the system's reliability, especially on quantity, is an important problem which has not been researched much yet.Note that there are lots of differences between software trust and hardware trust, especially when there's a great deal of human interference in the development of software. So how to describe all kinds of human interference in quantity research of software trust is a difficult problem.Consider all the reasons above, this paper presented an initial quantity research on software trust based on the software engineering and information security.First, the gradations of the software were measured by grade measurement. To measure software trust, we should distinguish the difference among the essence characters which were essential to software, characters which can be judged by relevant standard and characters which can be judged by experts. The quantity methods of these three characters are different.Second, the software trust tree was proposed based on the judging tree. And the system structure of the tree was build and analyzed. Then the steps of evaluating software trust were presented.Third, the quantitative research of software trust was discussed based on half-quantitative measures of Delphi method. Then a system prototype was developed using software engineering techniques.Finally, a function test was presented based on the evaluating system of software trust. And the test results were analyzed vertically and transversely and conclusions from the tests were given.