Privacy-aware role based access control

Chapter 23 - Policies, Access Control, and Formal Methods

Dynamically monitoring the state changes of an underlying system, detecting and reacting to changes without delay are crucial for the success of any access control enforcement mechanism. With their inherent nature, active (Event- Condition-Action or ECA) rules are prospective candidates to carry out change detection and to provide access control. Current systems or models do not provide a flexible mechanism for enforcing Role-Based Access Control (RBAC) standard and its extensions in a seamless way, and do not adapt to policy or role structure changes in enterprises, which are indispensable to make RBAC usable in diverse domains. In this paper we will show how On-When-Then-Else authorization rules (or enhanced ECA rules) are used for enforcing RBAC standard and its extensions such as generalized temporal RBAC, control flow dependency constraints, privacy-aware RBAC, and so forth in a seamless way. Furthermore, these rules also provide active security. Large enterprises have hundreds of roles, which requires thousands of rules for providing access control, and generating these rules manually is error-prone and a cognitive-burden for non-computer specialists. Thus, in this paper, we will discuss briefly how these authorization rules can be automatically (or semi-automatically) generated from high level specifications of enterprise access control policies. We will also discuss the implementation using Sentinel+, an active object oriented system.

W3C Recommendations XML Encryption and XML-Digital Signature can be used to protect the confidentiality of and provide assurances about the integrity of XML documents transmitted over an insecure medium. The focus of this paper is how to control access to XML documents, once they have been received. This is particularly important for services where updates are sent to subscribers. We describe how certain access control policies for restricting access to XML documents can be enforced by encrypting specified regions of the document. These regions are specified using XPath filters and the policies are based on the hierarchical structure of XML documents. We also describe how techniques for assigning keys to a security lattice can be adapted to minimize the number of keys that are distributed to users and compare our approach with two other access control frameworks. Finally we consider how role-based access control can be used to enforce more complex access control policies.

The Pi-calculus has been developed to reason about behavioural equivalence. Different notions of equivalence are defined in terms of process interactions, as well as the context of processes. There are various extensions of the Pi-calculus, such as the SPI calculus, which has primitives to facilitate security protocol design.<br /> <br />Another area of computer security is access control research, which includes problems of access control models, policies and access control mechanism. The design of a unified framework for access control requires that all policies are supported and different access control models are instantiated correctly.<br /> <br />In this paper we will utilise the Pi calculus to reason about access control policies and mechanism. An equivalence of different policy implementations, as well as access control mechanism will be shown. Finally some experiences regarding the use of Pi-calculus are presented.

Access Control is becoming increasingly important for today ubiquitous systems. Sophisticated security requirements need to be ensured by authorization policies for increasingly complex and large applications. As a consequence, designers need to understand such policies and ensure that they meet the desired security constraints while administrators must also maintain them so as to comply with the evolving needs of systems and applications. These tasks are greatly complicated by the expressiveness and the dimensions of the authorization policies. It is thus necessary to provide policy designers and administrators with automated analysis techniques that are capable to foresee if, and under what conditions, security properties may be violated. In this paper, we consider this analysis problem in the context of the Role-Based Access Control (RBAC), one of the most widespread access control models. We describe how we design heuristics to enable an analysis tool, called asaspXL, to scale up to handle large and complex Administrative RBAC policies. We also discuss the capability of applying the techniques inside the tool to the analysis of location-based privacy policies. An extensive experimentation shows that the proposed heuristics play a key role in the success of the analysis tool over the state-of-the-art analysis tools.

As the amount of data being collected by service providers increases, privacy concerns increase for the data owners that must provide private data to get services. Legislative acts require enterprises protect the privacy of their customers and privacy policy frameworks such as P3P assist enterprises in demonstrating their privacy policies to customers (i.e. publishing privacy policy on websites). Unfortunately, defining these standards does not guarantee that the privacy policies are actually enforced since privacy is not central to conventional access control models. Furthermore, a privacy-preserving model should consider the privacy preferences of both data provider and data collector. This paper presents a Lattice-based Privacy Aware Access Control (LPAAC) Model. The key contribution is providing a privacy preserving model that enforces privacy policies and facilitates customization of privacy agreements and preferences of both data providers and organizations that collect data.

Traditional access control mechanisms prevent illegal access by controlling access right before executing an action; they belong to a class of a priori security solutions and, from this point of view, they have some limitations, like inflexibility in unanticipated circumstances. By contrast, a posteriori mechanisms enforce policies not by preventing unauthorized access, but rather by deterring it. Such access control needs evidence to prove violations. Evidence is derived from one or several log records, which trace each user's actions. Efficiency of violation detection mostly depends on the compliance of log records with the access control policy. In order to develop an efficient method for finding these violations, we propose restructuring log records according to a security policy model. We illustrate our methodology by applying it to the healthcare domain, taking care of the IHE (Integrating the healthcare enterprise) framework, particularly its basic security profile, ATNA (Audit Trail and Node Authentication). This profile defines log records established on the analysis of common health practice scenarios. We analyze and establish how ATNA log records can be refined in order to be integrated into an a posteriori access and usage control process, based on an expressive and contextual security policy like the OrBAC policy.

Access control and privacy policies change during the course of collaboration. Information is often shared with collaborators outside of the traditional “perimeterized” organizational computer network. At this point the information owner (in the legal data protection sense) loses persistent control over their information. They cannot modify the policy that controls who accesses it, and have that enforced on the information wherever it resides. However, if patient consent is withdrawn or if the collaboration comes to an end naturally, or prematurely, the owner may be required to withdraw further access to their information. This paper presents a system that enhances the way access control technology is currently deployed so that information owners retain control of their access control and privacy policies, even after information has been shared.

This paper proposes an extension of the conventional role-based access control (RBAC model) called enhanced role-based access control or ERBAC03 model. The model is developed for the role-based access control of information system resources in large organizations that have many branches. Each branch consists of many users with different roles. It is related to a specified static separation of duty constraint in order to prevent fraud of users. We analyze the result of RBAC and ERBAC03 models by a number of experiments based on users' locations. The result proves that the proposed ERBAC03 model eliminates the inaccuracy of access control administration that has incurred in the conventional RBAC model. Any conflicting role is not allowed to be added to the associated database tables.

Collaborative Working Environments (CWEs) are getting prominence these days. With the increase in the use of collaboration tools and technologies, a lot of sharing and privacy issues have also emerged. Due to its dynamic nature, a CWE needs to adapt the changes into accordingly. In this paper, we have implemented the Adaptive Dynamic Sharing and Privacy-aware Role Based Access Control (Adaptive DySP-RBAC) model which provides user’s information privacy to dynamically adapt the changes occurring in the system at any time. The proposed model has been implemented as a prototype and tested. Results have shown that our system efficiently and effectively adapts access rules according to the changes happening in a CWE along with preserving the user’s information privacy in the system.

Access control (AC) is a computer security requirement used to control, in a computing environment, what the user can access, when and how. Policy administration is an essential feature of an AC system. As the number of computers are in hundreds of millions, and due to the different organization requirements, applications and needs, various AC models are presented in literature, such as: Discretionary Access Control (DAC), Mandatory Access Control (MAC), Role Based Access Control (RBAC), etc. These models are used to implement organizational policies that prevent the unauthorized disclosure of sensitive data, protecting the data integrity, and enabling secure access and sharing of information. Each AC model has its own methods for making AC decisions and policy enforcement. However, due to the diversity of AC models and the various concerns and restrictions, its essential to find AC metamodels with higher level of abstraction. Access control metamodels serve as a unifying framework for specifying any AC policy and should ease the migration from an AC model to another. This study reviews existing works on metamodels descriptions and representations. But, are the presented metamodels sufficient to handle the needed target of controlling access especially in the presence of the current information technologies? Do they encompass all features of other AC models? In this paper we are presenting a survey on AC metamodels.

AI applications of data sharing in agriculture 4.0: A framework for role-based data access control

Access control (AC) is the core of every architectural solution for information security. Indeed, no effective protection scheme can abstract from the careful design of access control policies, and infrastructures underlying modern Industrial Networked Systems (INSs) are not exceptions from this point of view. This paper presents a comprehensive framework for INS access control. The proposed approach enables the description of both positive and negative AC policies, by applying the Role Based Access Control (RBAC) paradigm to typical INS implementations, while taking into account different levels of abstraction. Suitable techniques are adopted to check whether or not policies are correctly implemented in the system (verification). When conflicts are detected, possible (re)assignments of credentials to the system users are automatically computed, that can be adopted to correct anomalies (conflict resolution).

Cloud Computing are used to deliver services from share pool of computing resources. These resources are provided to the user using the internet. It has advantage over traditional computing services along with new challenge. These are data security, privacy, protection, access control, availability, authentication, scalability, lock-in and confidentiality. These are inherent security flaws of cloud technology due to openness, multi-tenancy, outsourcing of resources. Access control is a fundamental security mechanism but traditional access control like as mandatory, discretionary and role based access control are not suitable. These traditional existing access control model are not effective and feasible solutions for cloud. In this research work, novel access control framework is proposed that can address the security and privacy issues for cloud. The framework is based on dynamic trustworthiness of user and provides an effective and feasible access control solution for cloud. A multi layer security standard, policies and access control mechanism are provided with proposed framework. The access control is based on the trustworthiness of the user, which is demonstrated by static and dynamic trust evidence. The dynamic trustworthiness is used to reduce the possibility to perform unauthorized activities and ensures that only authorized user's access cloud resources. The prototype of the proposed framework is developed in NetLogo on Linux platform and demonstrated with test cases. The analysis of simulated results shows that proposed mechanism is highly efficient and robust under existing security threats.

We extend a particular access control framework, the Privilege Calculus, with a possibility to override denied access for increased flexibility in hard to define or unanticipated situations. We require the overrides to be audited and approved by appropriate managers. In order to automatically find the authorities who are able to approve an override, we present an algorithm for authority resolution. We are able to calculate from the access control policy who can approve an override without the need for any additional information.