Authorization is an open problem in Ambient Intelligence environments. The difficulty of implementing authorization policies lies in the open and dynamic nature of such environments. The information is distributed among various heterogeneous devices that collect, process, change, and share it. Previous work presented a fully distributed approach for reasoning with conflicts in ambient intellige...

Access control is a significant issue in any secure database system. In this paper, we develop a logic programming based approach for temporal decentralized authorization administration in which users can be delegated, granted or forbidden some access rights for restricted periods of time. Three major aspects are taken into consideration for the semantics of the program, the temporal authorizat...

Trust management is a promising approach for the authorization in distributed environment. There are two key issues for a trust management system: how to design high-level policy language and how to solve the compliance-checking problem [3, 4]. We adopt this approach to deal with distributed authorization with delegation. In this paper, we propose an authorization language AL, a human-understan...

Several models of authorization have been proposed for object-oriented databases supporting diierent levels of granularity. However, these models do not support authorization based on database contents and context. A way of handling context and content-dependent authorization is by using views. In this paper, we present a model of authorization, based on a view model proposed by Bertino 4], tha...

The authorization mechanisms in existing Grids are relatively static, so we present a dynamic authorization mechanism. Through the negotiation between users and resources, the Grid security management entities match the requests of the user and resource according to corresponding stipulations in security policies, form security contracts, and make authorization decisions. In order to reflect wh...

The Web service specifications managing authentication and authorization are still a work in progress. A large-scale application built today is in need of a solid authentication and authorization infrastructure. A role-based authentication, authorization and accounting (AAA) concept is able to provide the services needed, while it is possible to gain additional flexibility to handle the co-oper...

Authorization is still an open problem in Ambient Intelligence environments. The difficulty of implementing authorization policies lies in the open and dynamic nature of such environments. The information is distributed among various heterogeneous devices that collect, process, change and share it. Previous work presented a fully distributed approach for reasoning with conflicts in ambient ...

One crucial aspect of information technology for e-Society is security, where authorization is one of the three important factors, besides availability and integrity. During the past years Role-Based Access Control (RBAC) has been proven a sound method of modeling the authorization within an organization. Recently we introduced a novel distributed concept RBAC which is based on distributed gene...

Grid infrastructures provide an environment for high performance computing by combining heterogeneous, widely distributed computational resources into a single cohesive computing infrastructure. One of the key goals of grid computing infrastructure is to provide an environment where users can share resources across heterogeneous domains. In such an infrastructure security is the major concern. ...

In most systems, authorization is speciied using some low-level system-speciic mechanisms, e.g. protection bits, capabilities and access control lists. We argue that authorization is an independent semantic concept that must be separated from implementation mechanisms and given a precise semantics. We propose a logical approach to representing and evaluating authorization. Speciically, we intro...