This paper considers the optimal regulation of access charges, and the effect such regulation has on incentives for non-price discrimination. I show that when a vertically integrated firm is able to discriminate against rivals by means of non-price measures, optimal access charges must be set higher than in the case when no discrimination is possible since the level of the access charge affects...

We analyse competition between two retailers of broadband access when they differ in their ability to offer value-added services. One retailer is vertically integrated and controls the input-market for local access. This firm invests to increase the input quality (upgrading to broadband) before an access price regulation is set. We first show that access price regulation may lower consumer surp...

Role-Based Access Control (RBAC) has been increasingly popular due to its efficiency, flexibility, and scalability. Traditionally, RBAC is concerned with Separation of Duty (SoD) among roles and role hierarchies. However, there have been demands for extensions of RBAC as environments of RBAC systems have changed. As part of response to the demands, privacy RBAC and temporal RBAC have been propo...

P rotection technologies in common use [8] are capable of preventing corruption by viruses (e.g. through mandatory access control), detecting known viruses (e.g. by starching for them), detecting specific types of corruption as they occur (e.g. trapping the modification of executable files in certain ways), and detecting corruption before it causes significant damage (e.g. through cryptographic...

Ambient assisted living is a new interdisciplinary field aiming at supporting senior citizens in their home by means of embedded technologies. This domain offer an interesting challenge for providing dependability and security in a privacy-respecting way: in order to provide services in an emergency we cannot monitor on a second-by-second base a senior citizen. Beside being immoral, it would be...

Pervasive computing applications use the knowledge of the environment to provide better services and functionality to the end user. Access control for such applications needs to use contextual information. Towards this end, we proposed an access control model based on RBAC that uses the environmental contexts time and location to determine whether a user can get access to some resource. The mod...

As more and more information becomes centralized, controlling and managing access to sensitive data becomes increasingly challenging. Attribute-based access control (ABAC), which represents the latest milestone in the evolution of logical access control methods, is designed to address these challenges. It provides an attribute-based approach to accommodate a wide breadth of access control polic...

Information federations promise an enhanced collaboration between individual stakeholders in the life cycle of commercial products, including software and hardware products from arbitrary business sectors. However, information sharing across corporate borders must be controlled by tailored mechanisms for enforcing individual business confidentiality and integrity requirements. One influential c...

The open and anonymous of grid make the task of controlling access to sharing information more difficult, which cannot be addressed by traditional access control methods. In this paper, we identify access control requirements in such environments and propose a trust based access control framework for grid resource sharing. The framework is an integrated solution involving aspects of trust and r...

Even though the final objective of an access control model is to provide a framework to decide if actions performed by subjects on objects are permitted or not, it is not convenient to directly specify an access control policy using concepts of subjects, objects and actions. This is why the Role Based Access Control (RBAC) model suggests using the concept of role as a more abstract concept than...