An Access Control Model for NoSQL Databases

Current development platforms are web scale, unlike recent platforms which were just network scale. There has been a rapid evolution in computing paradigm that has created the need for data storage as agile and scalable as the applications they support. Relational databases with their joins and locks influence performance in web scale systems negatively. Thus, various types of non-relational databases have emerged in recent years, commonly referred to as NoSQL databases. To fulfill the gaps created by their relational counter-part, they trade consistency and security for performance and scalability. With NoSQL databases being adopted by an increasing number of organizations, the provision of security for them has become a growing concern. This research presents a context based abstract model by extending traditional role based access control for access control in NoSQL databases. The said model evaluates and executes security policies which contain versatile access conditions against the dynamic nature of data. The goal is to devise a mechanism for a forward looking, assertive yet flexible security feature to regulate access to data in the database system that is devoid of rigid structures and consistency, namely a document based database such as MongoDB

Toward Effective Access Control Using Attributes and Pseudoroles

Sharing of information is fundamental to modern computing environments across many application domains. Such information sharing, however, raises security and privacy concerns that require effective access control to prevent unauthorized access and ensure compliance with various laws and regulations. Current approaches such as Role-Based Access Control (RBAC), and Attribute-Based Access Control (ABAC) and their variants are inadequate. Although it provides simple administration of access control and user revocation and permission review, RBAC demands complex initial role engineering and makes access control static. ABAC, on the other hand, simplifies initial security setup and enables flexible access control, but increases the complexity of managing privileges, user revocation and user permissions review. These limitations of RBAC and ABAC have thus motivated research into the development of newer models that use attributes and policies while preserving RBAC\u27s advantages. This dissertation explores the role of attributes---characteristics of entities in the system---in achieving effective access control. The first contribution of this dissertation is the design and development of a secure access system using Ciphertext-Policy Attribute-Based Encryption (CP-ABE). The second contribution is the design and validation of a two-step access control approach, the BiLayer Access Control (BLAC) model. The first layer in BLAC checks whether subjects making access requests have the right BLAC pseudoroles---a pseudorole is a predefined subset of a subject\u27s static attributes. If requesting subjects hold the right pseudoroles, the second layer checks rule(s) within associated BLAC policies for further constraints on access. BLAC thus makes use of attributes effectively while preserving RBAC\u27s advantages. The dissertation\u27s third contribution is the design and definition of an evaluation framework for time complexity analysis, and uses this framework to compare BLAC model with RBAC and ABAC. The fourth contribution is the design and construction of a generic access control threat model, and applying it to assess the effectiveness of BLAC, RBAC and ABAC in mitigating insider threats

An Access Control Model to Facilitate Healthcare Information Access in Context of Team Collaboration

The delivery of healthcare relies on the sharing of patients information among a group of healthcare professionals (so-called multidisciplinary teams (MDTs)). At present, electronic health records (EHRs) are widely utilized system to create, manage and share patient healthcare information among MDTs. While it is necessary to provide healthcare professionals with privileges to access patient health information, providing too many privileges may backfire when healthcare professionals accidentally or intentionally abuse their privileges. Hence, finding a middle ground, where the necessary privileges are provided and malicious usage are avoided, is necessary. This thesis highlights the access control matters in collaborative healthcare domain. Focus is mainly on the collaborative activities that are best accomplished by organized MDTs within or among healthcare organizations with an objective of accomplishing a specific task (patient treatment). Initially, we investigate the importance and challenges of effective MDTs treatment, the sharing of patient healthcare records in healthcare delivery, patient data confidentiality and the need for flexible access of the MDTs corresponding to the requirements to fulfill their duties. Also, we discuss access control requirements in the collaborative environment with respect to EHRs and usage scenario of MDTs collaboration. Additionally, we provide summary of existing access control models along with their pros and cons pertaining to collaborative health systems. Second, we present a detailed description of the proposed access control model. In this model, the MDTs is classified based on Belbin’s team role theory to ensure that privileges are provided to the actual needs of healthcare professionals and to guarantee confidentiality as well as protect the privacy of sensitive patient information. Finally, evaluation indicates that our access control model has a number of advantages including flexibility in terms of permission management, since roles and team roles can be updated without updating privilege for every user. Moreover, the level of fine-grained control of access to patient EHRs that can be authorized to healthcare providers is managed and controlled based on the job required to meet the minimum necessary standard and need-to-know principle. Additionally, the model does not add significant administrative and performance overhead.publishedVersio

Managing Access to Electronic Health Records in a Cloud Computing Environment

Access control methods are relevant in securing EHR from unauthorised users and access. It is therefore important that proper access control mechanisms are put in place in order to safeguard the privacy and confidentiality of health records. This paper provides a review of the benefits and limitations of individual access control mechanisms. It also indicate the challenges and advantages associated with the use of the individual access control methods vis-a-vis combined access control methods for accessing electronic health records (EHR) in a cloud computing environment. This review concludes that the use of one access control is not sufficient to fully secure EHR in a cloud computing environment. A combined access control methods has the potential to offer strong security to EHR in the cloud setting. Maximising the benefits of the various access controls is essential for enhancing the security of EHR in a cloud computing environment

IaaS-cloud security enhancement: an intelligent attribute-based access control model and implementation

The cloud computing paradigm introduces an efficient utilisation of huge computing resources by multiple users with minimal expense and deployment effort compared to traditional computing facilities. Although cloud computing has incredible benefits, some governments and enterprises remain hesitant to transfer their computing technology to the cloud as a consequence of the associated security challenges. Security is, therefore, a significant factor in cloud computing adoption. Cloud services consist of three layers: Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS). Cloud computing services are accessed through network connections and utilised by multi-users who can share the resources through virtualisation technology. Accordingly, an efficient access control system is crucial to prevent unauthorised access. This thesis mainly investigates the IaaS security enhancement from an access control point of view. [Continues.

Securing Controls Middleware of the Large Hadron Collider

The distributed control system of the Large Hadron Collider (LHC) presents many challenges due to its inherent heterogeneity and highly dynamic nature. One critical challenge is providing access control guarantees within the middleware. Role-based access control (RBAC) is a good candidate to provide access control. However, in an equipment control system transactions are often dependent on user context and device context. Unfortunately, classic RBAC cannot be used to handle the above requirements. In this paper we present an extended role-based access control model called CMW-RBAC. This new model incorporates the advantages of role-based permission administration together with a fine-grained control of dynamic context attributes. We also propose a new technique called dynamic authorization that allows phased introduction of access control in large distributed systems. This paper also describes motivation of the project, requirements, and overview of its main components: authentication and authorization

Context-Based Access for Infrequent Requests in Tanzania\u27s Health Care System

Access control is an important aspect of any information system. It is a way of ensuring that users can only access what they are authorised to and no more. This can be achieved by granting users access to resources based on pre-defined organisational and legislative rules. Although access control has been extensively studied, and as a result, a wide range of access control models, mechanisms and systems have been proposed, specific access control requirements for healthcare systems that needs to support the continuity of care in an accountable manner have not been addressed. This results in a gap between what is required by the application domain and what is actually practised, and thus access control solutions implemented for the domain become too restrictive. The continuity of care is defined as the delivery of seamless health care services to patients through integration, coordination and sharing of information between providers. This thesis, therefore, designs a context-based access control model that allows healthcare professionals to bypass access rules in an accountable manner in case of an infrequent access request involving an emergency situation. This research uses the Tanzania\u27s healthcare system as a case study domain

Task Delegation Based Access Control Models for Workflow Systems

International audiencee-Government organisations are facilitated and conducted using workflow management systems. Role-based access control (RBAC) is recognised as an efficient access control model for large organisations. The application of RBAC in workflow systems cannot, however, grant permissions to users dynamically while business processes are being executed. We currently observe a move away from predefined strict workflow modelling towards approaches supporting flexibility on the organisational level. One specific approach is that of task delegation. Task delegation is a mechanism that supports organisational flexibility, and ensures delegation of authority in access control systems. In this paper, we propose a Task-oriented Access Control (TAC) model based on RBAC to address these requirements. We aim to reason about task from organisational perspectives and resources perspectives to analyse and specify authorisation constraints. Moreover, we present a fine grained access control protocol to support delegation based on the TAC model