The cloud computing is a hot research area, because of its good features such as low investment, easy maintenance, flexibility, fast deployment and reliable service. At the same time, cloud computing can also reduce operating costs. The issue of trust is one of the biggest obstacles for usage of cloud computing. Today, one of the most important factors for the success of cloud computing is to build trust and security. Trust in cloud computing has a lot of issues like control, prevention, ownership and security. In this paper we have addressed the issue of trust in cloud computing. In cloud computing, users directly use and operate the software and operating system, and even basic programming environment and network infrastructure. So the impact and destruction for the software and hardware cloud resources in cloud computing are worse than the current internet users. Therefore, it is necessary to evaluate user's trustworthiness. So for evaluating the user level trustworthiness,we have defined policy based user level trust is evaluated. The User is categorized into different categories based on the user level trust value, number of policies violated and number of warnings received. This trust evaluation helps us to monitor the abnormal behavior of the user. Depending upon the user behavior, cloud service provider can restrict the user from accessing the cloud resources and also the user can be blacklisted.

Cloud Computing Trust User level Trust