Multidimensional Dynamic Trust Evaluation Scheme for Cloud Environment Abstract   In cloud computing environment, Cloud Customers (CCs) and Cloud Service Providers (CSPs) require to evaluate the trust levels of potential partner prior to appealing in communications. The accurateness of trust evaluation significantly influences the success velocity of the communication. Determining trustworthiness dynamically is a demanding problem in an open and dynamic environment (such as cloud computing) because of huge number of CSPs offering similar types of services. Also it is a challenging job for both CCs and CSPs to mutually recognize and distinguish between the trustworthy and untrustworthy CSPs and CCs. Presently, there are very less number of dynamic trust evaluation scheme that permits CCs to evaluate the trustworthiness of CSPs from multidimensional perspectives (i.e. perspectives from Cloud Auditors (CAs), Cloud Brokers (CBs), Service Level Agreement Agents (SLAAs) and Peers). Similarly, there is no scheme that permits CSPs to evaluate trustworthiness of CCs. This paper proposes a Multidimensional Dynamic Trust Evaluation Scheme (MDTES) that facilitates CCs to evaluate the trustworthiness of CSPs from various viewpoints. Similar approach can be employed by CSPs to evaluate the trustworthiness of CCs. The proposed MDTES helps CCs to choose trustworthy CSP which provides desired QoS and CSPs to choose desired and legal CCs. The experimental results illustrate that the MDTES is dynamic, efficient and steady in distinguishing trustworthy and untrustworthy CSPs and CCs compared to other trust models.

Trustworthiness Assessment of Web Applications: Approach and Experimental Study using Input Validation Coding Practices The popularity of web applications and their worldwide use to support business critical operations raised the interest of hackers on exploiting security vulnerabilities to perform malicious operations. Fostering trust calls for assessment techniques that provide indicators about the quality of a web application from a security perspective. This paper studies the problem of using coding practices to characterize the trustworthiness of web applications from a security perspective. The hypothesis is that applying feasible security practices results in applications having a reduced number of unknown vulnerabilities, and can therefore be considered more trustworthy. The proposed approach is instantiated for the concrete case of input validation practices, and includes a Quality Model to compute trustworthiness scores that can be used to compare different applications or different code elements in the same application. Experimental results show that the higher scores are obtained for more secure code, suggesting that it can be used in practice to characterize trustworthiness, also providing guidance to compare andor improve the security of web applications.