In web service technology the hazard of security is growing, such as the problem of access control. Recently, trust management is considered as an effective approach for enhancing web sen/ices security. In this paper, we focus on a two-level trust evaluation based access control system for web service environment. The model considers direct trust and recommended trust comprehensively between domains. This system is dynamic and can realize access control across domains by evaluating the comprehensive trust correctly and effectively. This trust model has a good performance even though under the condition of malicious recommendations by malicious domains that the percentage of secure access is high.

Keywords:Trust, Webservice, Access control I