A model for CPS software system trustworthiness evaluation based on attributes classifying

Cyber-Physical System is a kind of new systems by combining physical world with computation processes. There are many kinds of software in Cyber-Physical System, and the software system is composed of them. It´s difficult for the software system to examine the attributes such as correctness, safety, reliability by using software testing or formal method. So we propose a model for CPS software system trustworthiness evaluation based on trustworthiness attributes. Firstly, present a method to calculate the satisfaction of trustworthiness attributes by considering the aging of trustworthiness evidences; secondly, based on the weight distribution, a software trustworthiness calculating method is brought forward. Then based on the trustworthiness of software and the logical structures of the software system, we present a method to evaluate the trustworthiness level of CPS software system. At Last, we use an example to explain the effectiveness of the model.