We extend the separation kernel abstraction to represent the enforcement of the principle of least privilege. In addition to the inter-block flow control policy prescribed by the traditional separation kernel paradigm, we describe an orthogonal finer-grained flow control policy by extending the protection of elements to subjects and resources, as well as blocks, within a partitioned system. We ...

The genesis of immune privilege high in the evolutionary tree suggests that immune privilege is necessary, if not advantageous for the progressive development of the CNS. Upon reaching a certain degree of complexity, it seems as if the CNS was obliged to restrain the immune system from penetrating the blood-brain barrier. CNS autoimmunity against myelin proteins is known to be a contributory fa...

In this paper, we describe a general method for controlling the behavior of mobile agent-system entities through the allocation of privileges. Privileges refer to policy rules that govern the access and use of computational resources and services. The scheme is based on the capability of most mobile agent systems to extend the platform processing environment and the use of two forms of privileg...

We address the issue of updating privileges in a dynamic environment by introducing authority cerrtificates in a Privilege Management Infrastructure. These certificates can be used to create access-level permissions but also to delegate authority to other agents, thereby providing a mechanism for creating management structures and for changing these structures over time. We present a semantic f...

Most Windows users run all the time with Administrator privileges, equivalent to root privileges on a UNIX system. The possession of Administrator privileges by every user significantly increases the vulnerability of Windows systems. For example, simply compromising a user network service, such as an instant messaging client, provides an attacker complete control of the system. We address this ...

Alopecia areata is considered to be a cell-mediated autoimmune disease, in which autoreactive cytotoxic T cells recognize melanocyte-associated proteins such as tyrosinase. This review discusses recent advances in the understanding of the pathogenesis of alopecia areata, focusing on immunobiology and hormonal aspects of hair follicles (HFs). The HF is a unique "miniorgan" with its own immune an...

This paper describes a method for controlling the behavior of mobile agent-system entities through the allocation of privileges. Privileges refer to policy rules that govern the access and use of computational resources and services by mobile agents. Our method is based on extending the platform processing environment, using the capabilities present in most mobile agent systems, and applying tw...

Shubik’s (all-pay) dollar auction is a simple yet powerful auction model that aims to shed light on the motives and dynamics of conflict escalation. Common intuition and experimental results suggest that the dollar auction is a trap, inducing conflict by its very design. However, O’Neill [1986] proved the surprising fact that, contrary to the experimental results and the intuition, the dollar a...

In this paper we prove that the principles in the language with relation composition and dynamic implication, valid for all binary relations, are the same ones as the principles valid when we restrict ourselves to DPL-relations, i.e., relations generated from conditions (tests) and resettings.

The dollar auction is an auction model used to analyse the dynamics of conflict escalation. In this paper, we analyse the course of an auction when participating players are spiteful, i.e., they are motivated not only by their own profit, but also by the desire to hurt the opponent. We investigate this model for the complete information setting, both for the standard scenario and for the situat...