Trust aware cryptographic role based access control scheme for secure cloud data storage

In this paper, we propose a role-based access control (RBAC) system for data resources in the Storage Resource Broker (SRB). The SRB is a Data Grid management system, which can integrate heterogeneous data resources of virtual organizations (VOs). The SRB stores the access control information of individual users in the Metadata Catalog (MCAT) database. However, because of the specific MCAT schema structure, this information can only be used by the SRB applications. If VOs also have many non-SRB applications, each with its own storage format for user access control information, it creates a scalability problem with regard to administration. To solve this problem, we developed a RBAC system with Shibboleth, which is an attribute authorization service currently being used in many Grid environments. Thus, the administration overhead is reduced because the role privileges of individual users are now managed by Shibboleth, not by MCAT or applications. In addition, access control policies need to be specified and managed across multiple VOs. For the specification of access control policies, we used the Core and Hierarchical RBAC profile of the eXtensible Access Control Markup Language (XACML); and for distributed administration of those policies, we used the Object, Metadata and Artifacts Registry (OMAR). OMAR is based on the e-business eXtensible Markup Language (ebXML) registry specifications developed to achieve interoperable registries and repositories. Our RBAC system provides scalable and fine-grain access control and allows privacy protection. Performance analysis shows that our system adds only a small overhead to the existing security infrastructure of the SRB.

The increased complexity of modern access control (AC) systems stems partly from the need to support diverse and multiple administrative domains. Systems engineering is a key technology to manage this complexity since it is capable of assuring that an operational system will adhere to the initial conceptual design and defined requirements. Specifically, the verification stage of an AC system should be based on techniques that have a sound and mathematical underpinning. Working on this assumption, model checking techniques are applied for the verification of predefined system properties, and thus, conducting a security analysis of a system. In this paper, we propose the utilization of automated and error-free model checking techniques for the verification of security properties in multi-domain AC systems. Therefore, we propose a formal definition in temporal logic of four AC system properties regarding secure inter-operation with Role-Based Access Control (RBAC) policies in order to be verified by using model checking. For this purpose, we demonstrate the implementation of a tool chain for expressing RBAC security policies, reasoning on role hierarchies and properly feeding the model checking process. The proposed approach can be applied in any RBAC model to efficiently detect non-conformance between an AC system and its security specifications. As a proof of concept, we provide examples illustrating the verification of the defined secure inter-operation properties in multi-domain RBAC policies.

We propose an exception resolution service for a role based access control (RBAC) system as a supplementary service, that will increase the flexibility of RBAC systems. Our model will keep the security policies based on a RBAC system while some not role based administrations are possible. In other words, the not role based access permission is not independent from the RBAC system. The related definitions and functions are given. An implementation example shows that the service is useful and efficient in practice.

The complexity of the ATLAS experiment motivated the deployment of an integrated Access Control System in order to guarantee safe and optimal access for a large number of users to the various software and hardware resources. Such an integrated system was foreseen since the design of the infrastructure and is now central to the operations model. In order to cope with the ever growing needs of restricting access to all resources used within the experiment, the Roles Based Access Control (RBAC) previously developed has been extended and improved. The paper starts with a short presentation of the RBAC design, implementation and the changes made to the system to allow the management and usage of roles to control access to the vast and diverse set of resources. The RBAC implementation uses a directory service based on Lightweight Directory Access Protocol to store the users (∼3000), roles (∼320), groups (∼80) and access policies. The information is kept in sync with various other databases and directory services: human resources, central CERN IT, CERN Active Directory and the Access Control Database used by DCS. The paper concludes with a detailed description of the integration across all areas of the system.

Role-based access control (RBAC) continues to gain popularity in the management of authorization concerning access to knowledge assets in organizations. As a socio-technical concept, the notion of role in RBAC has been overemphasized, while very little attention is given to the precursors: role strain, role ambiguity, and role conflict. These constructs provide more significant insights into RBAC design in Knowledge Management Systems (KMS). KMS is the technology-based knowledge management tool used to acquire, store, share, and apply knowledge for improved collaboration and knowledge-value creation. In this paper, we propose eight propositions that require future research concerning the RBAC system for knowledge security. In addition, we propose a model that integrates these precursors and RBAC to deepen the understanding of these constructs. Further, we examine these precursory constructs in a socio-technical fashion relative to RBAC in the organizational context and the status–role relationship effects. We carried out conceptual analysis and synthesis of the relevant literature, and present a model that involves the three essential precursors that play crucial roles in role mining and engineering in RBAC design. Using an illustrative case study of two companies where 63 IT professionals participated in the study, the study established that the precursors positively and significantly increase the intractability of the RBAC system design. Our framework draws attention to both the management of organizations and RBAC system developers about the need to consider and analyze the precursors thoroughly before initiating the processes of policy engineering, role mining, and role engineering. The propositions stated in this study are important considerations for future work.

In the past five years there has been tremendous activity in role-based access control (RBAC) models. Consensus has been achieved on a standard core RBAC model that is in process of publication by the US National Institute of Standards and Technology (NIST). An early insight was that RBAC cannot be encompassed by a single model since RBAC concepts range from very simple to very sophisticated. Hence a family of models is more appropriate than a single model. The NIST model reflects this approach. In fact RBAC is an open-ended concept which can be extended in many different directions as new applications and systems arise. The consensus embodied in the NIST model is a substantial achievement. All the same it just a starting point. There are important aspects of RBAC models, such as administration of RBAC, on which consensus remains to be reached. Recent RBAC models have studied newer concepts such as delegation and personalization, which are not captured in the NIST model. Applications of RBAC in workflow management systems have been investigated by several researchers. Research on RBAC systems that cross organizational boundaries has also been initiated. Thus RBAC models remain a fertile area for future research. In this paper we discuss some of the directions which we feel are likely to result in practically useful enhancements to the current state of art in RBAC models.KeywordsAccess ControlAccess Control ModelRBAC ModelMandatory Access ControlSpringer LNCSThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Separation-of-duty (SoD) is widely considered to be a fundamental principle to role based access control (RBAC) models and systems should adhere. In this paper, we formulate and study the fundamental problem of SoD policies in the context of RBAC systems. We give a set-based specification of SoD policies and the safety checking problem for SoD policies in the context of RBAC. We study the problem of determining whether a SoD policy is enforceable, and show that directly enforcing SoD policies in RBAC is intractable (coNP-complete). Moreover, indirectly enforcing SoD policies by using mutually exclusive role constraints is also intractable (NP-hard). Therefore, we reduce the safety checking problem for SoD to SAT4J problem which can be solved using available SAT solvers. The experiments show the validity and effectively of the SAT approach.

Role based Access Control (RBAC) is known as an evolution in the field of access control. The strength of RBAC is considered due to the incorporation of concept of roles. Separation of Duty (SOD) is a constraint that implements least privilege principle in RBAC. Dynamic Separation of Duty (DSD) is a powerful constraint to control internal security threats. Current RBAC standard implements DSD on the level of roles. This creates various problems. In this paper, various problems in case of implementing DSD on the level of roles are identified. We show and prove that RBAC's strength is the incorporation of concept of roles but this is not for better security in terms of authorization. Instead this helps in better administration or usability for users. The RBAC usability can be improved if RBAC administration is being implemented on the basis of roles and access control can be more secure if DSD is being implemented on the basis of conflicting permissions. The concept of normalized roles is also introduced. The proposed model implements access control on the basis of normalized role. DSD is being implemented on the basis of conflicting permissions and non-conflicting permissions are exercised under the umbrella of role. This becomes a hybrid approach for access control. The administrators are given freedom in implementing DSD in various modes according to the organizational requirements from lenient to strict implementation. The proposed model is also formally specified and the benefits as a result of implementing the proposed model are discussed.

With the rapid developments occurring in cloud computing and services, there has been a growing trend to use the cloud for large-scale data storage. This has raised the important security issue of how to control and prevent unauthorized access to data stored in the cloud. One well known access control model is the role-based access control (RBAC), which provides flexible controls and management by having two mappings, users to roles and roles to privileges on data objects. In this paper, we propose a role-based encryption (RBE) scheme that integrates the cryptographic techniques with RBAC. Our RBE scheme allows RBAC policies to be enforced for the encrypted data stored in public clouds. Based on the proposed scheme, we present a secure RBE-based hybrid cloud storage architecture that allows an organization to store data securely in a public cloud, while maintaining the sensitive information related to the organization's structure in a private cloud. We describe a practical implementation of the proposed RBE-based architecture and discuss the performance results. We demonstrate that users only need to keep a single key for decryption, and system operations are efficient regardless of the complexity of the role hierarchy and user membership in the system.

Towards more pro-active access control in computer systems and networks

Recently there has been considerable interest in role-based access control (RBAC) as an alternative, and supplement, to the traditional discretionary and mandatory access controls (DAC and MAC) embodied in the Orange Book. The roots of RBAC can be traced back to the earliest access control systems. Roles have been used in a number of systems for segregating various aspects of security and system administration. Recent interest in RBAC has been motivated by the use of roles at the application level to control access to application data. This is an important innovation which offers the opportunity to realize benefits in securing an organization's information assets, similar to the benefits of employing databases instead of files as the data repository. A number of proposals for RBAC have been published in the literature, but there is no consensus on precisely what is meant by RBAC. This paper lays the groundwork for developing this consensus. In our view RBAC is a concept which has several dimensions, all of which may not be present in a given system or product. We envisage each dimension as being linearly ordered with respect to the sophistication of features provided. This leads us to the idea of a multi-dimension model for RBAC. Achieving agreement on what these dimensions are, and how the features in each dimension should be ordered, will take debate and time. Our contribution here is to lay out a vision on how to approach a common understanding of RBAC, and take a first cut at identifying the dimensions of RBAC. A major benefit of such a multidimensional RBAC would be to allow comparison of different products and assess their appropriateness for various system requirements.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

In many domains, organizations must model personnel and corresponding data access privileges as fine-grained hierarchical access control models. One class of such models, Role-based Access Control (RBAC) models, has been widely accepted and deployed. However, RBAC models are often used without involving cryptographic keys nor considering confidentiality/privacy at the data level. How to design, implement and dynamically modify such a hierarchy, ensure user and data privacy and distribute and manage necessary cryptographic keys are issues of the utmost importance. One elegant solution for cryptography-based hierarchical access control combines the collusion-resistant and privacy-preserving Access Control Polynomial (ACP) and Atallah's Dynamic and Efficient Extended Key Management scheme. Such a model involves cryptographic keys used to encrypt data, can address confidentiality/privacy at the data level and can efficiently support dynamic changes to the RBAC access hierarchy. In this paper, we discuss several implementation challenges and propose solutions when deploying such a system including: data encryption and decryption, key storage and key distribution. Furthermore, we provide analysis of the efficiency and scalability of the resulting system.

Several researches in recent years have pointed out that for the proper enforcement of privacy policies within enterprise data handling practices the privacy requirements should be captured in access control systems. In this paper, we extend the role-based access control (RBAC) model to capture privacy requirements of an organization. The proposed purpose-aware RBAC extension treats purpose as a central entity in RBAC. The model assigns permissions to roles based on purpose related to privacy policies. Furthermore, the use of purpose as a separate entity reduces the complexity of policy administration by avoiding complex rules and applying entity assignments, coherent with the idea followed by RBAC. Our model also supports conditions (constraints and obligations) with clear semantics for enforcement, and leverages hybrid hierarchies for roles and purposes for enforcing fine grained purpose and role based access control to ensure privacy protection.

The traditional mandatory access control policy (MAC) is regarded as a policy with strict regulation and poor flexibility. The security policy of MAC is so compelling that few information systems would adopt it at the cost of facility, except some particular cases with high security requirement as military or government application. However, with the increasing requirement for flexibility, even some access control systems in military application have switched to role-based access control (RBAC) which is well known as flexible. Though RBAC can meet the demands for flexibility but it is weak in dynamic authorization and consequently can not fit well in the workflow management systems. The task-role-based access control (T-RBAC) is then introduced to solve the problem. It combines both the advantages of RBAC and task-based access control (TBAC) which uses task to manage permissions dynamically. To satisfy the requirement of system which is distributed, well defined with workflow process and critically for time accuracy, this paper will analyze the spirit of MAC, introduce it into the improved T&RBAC model which is based on T-RBAC. At last, a conceptual task-role-based access control model with high security for distributed workflow and real-time application (A_T&RBAC) is built, and its performance is simply analyzed.

The popularity of web applications and platforms for collecting big data has set the goal of efficient data storage. NoSQL databases have become widely used for data storage and scaling. However, there are also a number of problems associated with the choice of efficient data storage and data schemes. The solution of these problems requires an understanding of the runtime conditions and possible loading of the system, which relies primarily on dedicated computing resources. The same data storage schemes can show different efficiency while under different critical load conditions or different computing infrastructures. In this paper, we propose a framework and experiment methodology for two NoSQL storage schemes that allow us to evaluate the most preferred option in the design of the developed application. The paper presents an analysis of the efficiency of two database schemas for maintaining a reliable saving of semi-structured data stream with specified characteristics.