Policy expression and checking in XACML, WS-Policies, and the jABC

Web-based access to sensitive and confidential data is realized today via different approaches, using a variety of methods to specify and combine access control policies. In an optic of change management and evolution, a structured and flexible model is needed to handle dynamicity, particularly when handling rights in systems with many users which hold different roles. Furthermore the validation of security constraints is an important key to warrant the reliability of control mechanisms. This paper compares the temporal logic-based approach for modeling access control used by the jABC framework with two popular XML-based description languages (XACML and WS-Policy), which are quasi-standards for policy expression in Web applications. Its usage is illustrated here on the example of the web-based Online Conference Service (OCS). The respective functionalities are described and examined in consideration of their ability to validate and enforce the needed policies.