Research on key-based trust model

In the distributed environments, Anonymous Access and Delegation are not satisfied in the traditional Access Control. However, they can be guaranteed in the Key-based Trust Models, because a key represents the identification of one user, both authorization and key are associated with each other. In the Key-based Trust Models, the most representative ones are PolicyMaker, SPKI/SDSI and QCM. In this paper, we extract the mechanisms of authorization from these models, discuss the advantages and disadvantages, so as to develop new studies and applications.