A Trust Reputation Architecture for Virtual Organization Integration in Cloud Computing Environment

Virtual Organization (VO) represents a prominent collaboration initiative, where a set of entities share competencies and risks attending a common goal. Moreover, their interactions can be supported in an Internet basis, using Cloud Computing (CC) resources. The VO and CC integration brings several benefits, such as: reduction of costs and maintenance, interoperability, among others. However, there are issues related to privacy, trust and security that need to be addressed. One of the issues observed is how much trust VO members put in the cloud provider (CP), particularly, in a scenario where VO members use the resources provided by a CP to made available their services and in order to interact with other members. Thus, the proposed reputation architecture intends to assist the decision-making processes present in the VO's life-cycle reputing CP trust. The reputed trust is based on two sources: a) objective (Quality of Service (QoS) indicators) and b) subjective (feedback from users regarding those QoS indicators). The evaluation results show that the architecture is resilient to attacks on subjective trust during the reputation calculation. Also, it is possible to note that the proposed architecture presents an acceptable average time for each one operation, and a significant role during VO's creation and operation.