The evolution of cloud computing is driving the next generation of diagnostic imaging (DI) systems. Migrating DI systems to cloud platform is cost-effective and improves the quality of DI services. However, a major challenge is managing the identity of various participants (users, devices, applications) and ensuring that all service providers offer equivalent access control in cloud ecosystem. ...

We present a formal, tool-supported approach to the design and maintenance of access control policies expressed in the eXtensible Access Control Markup Language (XACML). Our aim is to help developers evaluate the consequences of policy decisions in complex situations where security requirements change and access decisions may depend on the external dynamic environment. The approach applies the ...

This paper presents an infrastructure that enables the use of administrative delegation in an effective way, reducing the complexity in the policy management for some specific scenarios. This infrastructure is in charge of managing the policies of the system during its lifecycle, for example when they are created by the users or when they are collected to take an authorization decision. The pro...

In dynamic collaboration, participants oftentimes need to share resources with each other under the same criteria. However, since each participant has its own authorization policies as a way of controlling resource access, their discrepancies make such collaboration difficult. It is desired to develop a practical and automatic way to generate the collaborative policies for coequal authorization...

Service-oriented architectures (SOAs) are increasingly gaining popularity due to their considerable flexibility and scalability in open IT-environments. Along with their rising acceptance comes the need for well suited security components. In this respect, access control and privacy emerged to crucial factors. Targeting the demands of a SOA, many promising authorization models have been develop...

The XACML is the access controller of the World Wide Web (WWW). The current reference implementation has a single policy decision point and a policy enforcement point. If XACML policies are used to control workflow among cooperating web services, such as those envisioned in more contemporary languages like (BPEL), it requires coordination to be policy compliant. We propose the necessary enhance...

Dramatic growth in the number of subscribers in Online Social Networks (OSNs), such as Facebook, MySpace, Orkut, etc. shows their increasing popularity among people from different ages and sectors. However, currently, the users need to put complete trust on OSN service providers, to protect their sensitive information because of centralized access control at the providers. Taking advantage of t...

Usage control model (UCON) is one of the emerging and comprehensive attribute based access control model that has the ability of monitoring the continuous updates in a system making it better than the other models of access control. UCON is suitable for the distributed environment of grid and cloud computing platforms however the proper formulation of this model does not exist in literature in ...

ion: details about other policy of other domains are not required Independent: definition of policies is done by the Authoritative Domain Adaptive: policies support dynamic references to other authoritative domains Bridging: translation of local attribute names and value space into those of referred ones Transparency: location of the referred domain with respect to end-points is not explicitly ...