An XML-based language for access control specifications in an RBAC environment

Lately, Web-accessed resources have superceded the resources accessed by local or wide-area networks. Therefore, new mechanisms should be implemented for protecting resources from unknown clients. Attribute Certificates is a quite new technology offering such functionality. Those certificates are issued by Attribute Authorities validating the attributes of the owner of the certificate. Based on this technology an XML-based access control mechanism is introduced for protecting any kind of resources (from both known and unknown clients). The proposed model is ultimately role-based since both clients and protected resources are organized into roles. Moreover, an XML-based language is introduced to express roles, authorizations, delegation rules, hierarchies and certificates.