Anna Felkner

The semantics of role-based trust management languages

Role-based Trust management (RT) languages are used for representing policies and credentials in decentralized, distributed access control systems. RT languages combine trust management and role-based access control features. A credential provides information about the keys, rights and qualifications from one or more trusted authorities. The paper presents a set-theoretic semantics of Role-based Trust management languages, which maps a role to a set of sets of entity names. The semantics applies not only to the basic language of the family RT 0 , but also to a much more sophisticated RT T , which provides manifold roles and role-product operators to express threshold and separation-of-duty policies. A manifold role defines sets of entities whose cooperation satisfies the manifold role. It enables to express a such a condition, which need more than one member of a role to effectively fulfill the particular task.

Time Validity in Role-Based Trust Management Inference System

The topic of this paper is RT T , a language from the family of Role-based Trust management (RT) languages, which is used for representing security policies and credentials in distributed large scale access control systems. A credential provides information about the privileges of users and the security policies issued by one or more trusted authorities. RT languages combine trust management and Role Based Access Control features. RT T provides manifold roles to express threshold and separation of duties policies. A manifold role defines sets of entities whose cooperation satisfies the manifold role. The goal of this paper is introduction of time validity constraints to show how that can make RT T language more realistic. The core part of the paper describes a sound and complete inference system, in which credentials can be derived from an initial set of credentials using a set of inference rules.

Secure Workstation for Special Applications

The paper presents the recently started project which aims to develop a secure environment for processing of restricted information. The solution being developed by the consortium employs virtualization to allow data from different security domains to be processed on the same physical machine. The system can host Windows and Linux systems as secured guest operating systems. The proposed implementation offers advanced user authentication techniques and cryptographic protection. The project is expected to reach technology demonstrator phase in late 2012.

More practical application of Trust management credentials

Trust management is an approach to access control in distributed open systems, where access control decisions are based on policy statements made by multiple principals. The family of Role-based Trust management languages (RT) is an effective means for representing security policies and credentials in decentralized, distributed, large scale access control systems. It provides a set of role assignment credentials. A credential provides information about the privileges of users and the security policies issued by one or more trusted authorities. The main purpose of this paper is to show how extensions can make the RT family languages more useful in practice. It shows how security policies can be made more realistic by including timing information, maintaining the procedure or parameterizing the validity of credentials.

Modeling Trust Management and Security of Information

This paper is a survey of studies of modeling access control and trust management. Access control is an important requirement of information systems. Role Based Access Control (RBAC) is the most flexible type of access control policy. It is a model of access control in enterprise information systems. It uses a user role to control which users have access to given resources. Access rights are grouped by a role name, and access to resources is restricted to these users who are assigned to appropriate roles. Each user can be assigned to one or more roles, which itself can be associated with one or more privileges. Conventional access control models are suitable for regulating access to resources by recognized users. Unfortunately, these models have often been inadequate for decentralized and open systems where the identity of the users is not known and users are changing constantly. To overcome the shortcomings of conventional access control models, like RBAC, credential-based access control has been proposed. Credential-based systems implement a notion of binary trust. However, due to the monotonicity requirement, these models will be more appropriate for a theoretical analysis than for real use. Non monotonic Trust Management system for P2P applications is also described.

Practical Extensions of Trust Management Credentials

Trust management is a unified approach to access control in open distributed systems, where decisions connected with access control are based on policy statements made by many principals. The family of Role-based Trust management languages (RT) is an effective means for representing security policies, credentials and relationship in distributed, decentralized, large scale access control systems. It delivers a set of role assignment credentials and is used in systems where the identities of users are not the most important form of identification. A credential gives information about the privileges of users and the security policies issued by (usually more than one) trusted authorities. The main purpose of this article is to show how some credential extensions can make a trust management system more useful in practice. It shows how security systems can be made more realistic by maintaining the procedure or including timing information.

Simulation of Critical ICT Infrastructure for Municipal Crisis Management

Crisis management benefits tremendously from simulation, especially during the planning and testing. At the same time an often overlooked aspect of crisis management is the key role of telecommunication. This paper describes the work done at NASK with the goal of implementing a simulator of the consequences of threats to the ICT (Information and Communication Technology) infrastructure, as a part of a large simulation environment for crisis management in a large urban area (specifically the Warsaw agglomeration).