Policy analysis for self-administrated role-based access control

Current techniques for security analysis of administrative role-based access control (ARBAC) policies restrict themselves to the separate administration assumption that essentially separates administrative roles from regular ones. The naive algorithm of tracking all users is all that is known for the security analysis of ARBAC policies without separate administration, and the state space explosion that this results in precludes building effective tools. In contrast, the separate administration assumption greatly simplifies the analysis since it makes it sufficient to track only one user at a time. However, separation limits the expressiveness of the models and restricts modeling distributed administrative control. In this paper, we undertake a fundamental study of analysis of ARBAC policies without the separate administration restriction, and show that analysis algorithms can be built that track only a bounded number of users, where the bound depends only on the number of administrative roles in the system. Using this fundamental insight paves the way for us to design an involved heuristic to further tame the state space explosion in practical systems. Our results are also very effective when applied on policies designed under the separate administration restriction. We implement our techniques and report on experiments conducted on several realistic case studies

Оцінка механізмів мережевої безпеки на основі політики RBAC

Об’єкт дослідження: процес управління доступом до ресурсів інформаційної системи. Мета роботи:оцінка механізмів мережевої безпеки та впровадження моделі RBAC для вирішення питання розподілу рольового доступу при великій кількості користувачів. Методи дослідження: методи індукції, аналізу і синтезу (при розкритті теоретичних положень); метод обробки інформації (при розрахунках параметрів). У спеціальній частині дана характеристика моделі RBAC, поняття про мережеву безпеку та описуються проблеми які виникають при контролі доступу серед користувачів. В економічному розділі визначені витрати на дослідження та розробку моделі GB-RBACта у порівнянні доведено доцільність цих витрат зі зменшенням збитку. Практичне значення роботи полягає у застосуванні моделі GB-RBAC та її переваги перед іншими. Проведено аналіз доцільності моделі для вирішення поставлених задач. Наукова новизна дослідження полягає у покращенні захисту мережевої безпеки та зменшення навантаження на мережу та на системного адміністратора, тому підвищується якість та цілісність мережі

Author's personal copy Roles in information security e A survey and classification of the research area

Motivation The growing diffusion of information technologies within all areas of human society has increased their importance as a critical success factor in the modern world. However, information processing systems are vulnerable to many different kinds of threats that can lead to various types of damage resulting in significant economic losses. Consequently, the importance of Information Security has grown and evolved in a similar manner. In its most basic definition, Information Security means protecting information and information systems from unauthorized access, use, disclosure, disruption, modification, or destruction. The aim of Information Security is to minimize risks related to the three main security goals confidentiality, integrity, and availability e usually referred to as "CIA" c o m p u t e r s & s e c u r i t y 3 0 ( 2 0 1 1 ) 7 4 8 e7 6 9 0167-4048/$ e see front matter

Analyzing and developing role-based access control models

Role-based access control (RBAC) has become today's dominant access control model, and many of its theoretical and practical aspects are well understood. However, certain aspects of more advanced RBAC models, such as the relationship between permission usage and role activation and the interaction between inheritance and constraints, remain poorly understood. Moreover, the computational complexity of some important problems in RBAC remains unknown. In this thesis we consider these issues, develop new RBAC models and answer a number of these questions. We develop an extended RBAC model that proposes an alternative way to distinguish between activation and usage hierarchies. Our extended RBAC model has well-defined semantics, derived from a graph-based interpretation of RBAC state. Pervasive computing environments have created a requirement for access control systems in which authorization is dependent on spatio-temporal constraints. We develop a family of simple, expressive and flexible spatio-temporal RBAC models, and extend these models to include activation and usage hierarchies. Unlike existing work, our models address the interaction between spatio-temporal constraints and inheritance in RBAC, and are consistent and compatible with the ANSI RBAC standard. A number of interesting problems have been defined and studied in the context of RBAC recently. We explore some variations on the set cover problem and use these variations to establish the computational complexity of these problems. Most importantly, we prove that the minimal cover problem -- a generalization of the set cover problem -- is NP-hard. The minimal cover problem is then used to determine the complexity of the inter-domain role mapping problem and the user authorization query problem in RBAC. We also design a number of efficient heuristic algorithms to answer the minimal cover problem, and conduct experiments to evaluate the quality of these algorithms.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Understanding and developing role-based administrative models

Access control data structures generally need to evolve over time in order to reflect changes to security policy and personnel. An administrative model defines the rules that control the state changes to an access control model and the data structures that model defines. We present a powerful framework for describing role-based administrative models. It is based on the concept of administrative domains and criteria that control state changes in order to preserve certain features of those domains. We define a number of different sets of criteria, each of which control the effect of state changes on the set of administrative domains and thereby lead to different role-based administrative models. Using this framework we are able to identify some unexpected connections between the ARBAC97 and RHA administrative models and to compare their respective properties. In doing so we are able to suggest some improvements to both models