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Currently, trusted execution environment technologies are widely used to enhance the security of connected devices such as mobile phones and tablets. The trusted operating system is the core component of a trusted execution environment solution, but the trusted operating system itself may face security challenges. The main reason is that the trusted operating system needs to provide different services for different application scenarios, which makes its function more complicated and further increases the code size. In most trusted execution environment solutions, the trusted operating system is based on Monolithic kernel architecture. This will inevitably face security issues such as software defects and lack of isolation between components. In this paper, we propose a scheme for design secure trusted operating system based on a microkernel architecture. In our scheme, we take the modified take-grant model as the system security model and design a discretionary access control mechanism based on the capability system. We implemented our secure trusted operating system on the i.MX6Q platform. The test results show that it works properly and meets the requirements of the GP TEE specifications.

Solid is a moderate re-decentralization architecture for the Web. In Solid, applications fetch data from storage providers called “pods” which implement discretionary access control, permitting users to grant and revoke access rights and thus keeping control over their data. In this paper, we propose to apply an additional de-verticalization by introducing IPFS as a common backend for Solid pods, the goal being to prevent pod provider lock-in and permitting users to consider “self-poding” where the heavy persistency task is out-sourced to IPFS. We have implemented this Solid-over-IPFS architecture using the open-source “Community Solid Server” and successfully ran several Solid applications over IPFS.

Role-based access control (RBAC) model has gained significant attention in cybersecurity in recent years. RBAC restricts system access only to authorized users based on the roles and regulations within an organization. The flexibility and usability of this model have encouraged organizations to migrate from traditional discretionary access control (DAC) models to RBAC. However, this transition requires accomplishing a very challenging task called role mining in which users' roles are generated from the existing access control lists. Although various approaches have been proposed to address this NP-complete problem in the literature, they suffer either from low scalability such that their execution time increases exponentially with the input size, or they rely on fast heuristics with low optimality that generate too many roles. In this paper, we introduce a highly scalable yet optimal approach to tackle the role mining problem. To this end, we utilize a non-negative rank reduced matrix decomposition method to decompose a large-scale user-permission assignment into two constitutive components, i.e. the user-role and role-permission assignments. Then, we apply a thresholding technique to convert real-valued components into binary-valued factors. We employ various access control configurations and demonstrate that our proposed model is able to effectively discover the latent relationship behind the user-permission data even with large datasets.

Recent regulations for security and privacy of personal data request new approaches in data access and retrieval processes. In the context of healthcare, the regulations point two types of consent to access sensitive personal medical data: explicit and implicit consent. This paper focus on explicit consent cases and presents an architecture where the patient grants on-demand access to private health records. The architecture is supported by a Discretionary Access Control model suited for cross-domain and cloud environments. Each resource belongs to a patient that has the power to grant or deny any access rights to users or groups of users. All the process is designed to be secure, from the authentication of the physician in the terminal until the communications between entities, passing by the physician’s terminal check by the patient. Furthermore, the security methods are discussed and evaluated. Finally, it is presented a summary of the developed work and the plans to apply in the future work.

The Internet of Things paradigm is growing rapidly. In fact, controlling this massive growth of IoT globally raises new security and privacy issues. The traditional access control mechanisms provide security to IoT systems such as DAC (discretionary access control) and mandatory access control (MAC). However, these mechanisms are based on central authority management, which raises some issues such as absence of scalability, single point of failure, and lack of privacy. Recently, the decentralized and immutable nature of blockchain technology integrated with access control can help to overcome privacy and security issues in the IoT. This paper presents a review of different access control mechanisms in IoT systems. We present a comparison table of reviewed access control mechanisms. The mechanisms’ scalability, distribution, security, user-centric, privacy and policy enforcing are compared. In addition, we provide access control classifications. Finally, we highlight challenges and future research directions in developing decentralized access control mechanisms for IoT systems.

In this paper, the issue of modeling the transformations of information links in the architecture of cybersecurity of systems with discretionary access control on graphs using the formal "take-grant" model for the task of synthesizing the cybersecurity architecture is considered. For various initial conditions of the problem, reflecting the requirements for the final state of the structure of information links, modeling algorithms based on the Ford-Fulkerson theorem and methods for finding the smallest edge section of a graph are proposed. A software module has been created that implements the proposed algorithms in Python using the NetworkX library. Examples of the results of the created software module are given.

Patient consent is currently a missing piece on Electronic Health Records System (EHR-S) access permission. The control is needed to ensure personal data as the property of the individual, not data controllers or health-care service providers. To cope with this need, in this article, an adaptation of existent Role-Based Access Control (RBAC), including patient-centric control, is described. The revisited feature of existing administrative and supporting RBAC functions allows exclusive control orchestrated by the patient as sole information owner, including the ability to encrypt their data for confidentiality purposes. The additions mimic a Discretionary Access Control (DAC) capability using existing user group membership to vet access over symmetric keys bind to patient's data via the associated PERMS matrix.

The protection of sensitive information in computer systems and networks from malicious manipulation is critical. As a key component in cybersecurity, access control is used to mitigate malicious access to sensitive information. To help students master the access control concepts, we developed a 2D educational game titled "Temple of Treasures" that aims to teach Discretionary Access Control (DAC), Access Control List (ACL) and Mandatory Access Control (MAC) in Unix/Linux Systems via a fun and interactive environment. The Unity3D game engine is used for game development and the game can be deployed to multiple platforms such as Windows, macOS, and web. Player information and in-game assessment data are saved on the cloud through GameSparks for analysis. The game story is centered around a group of adventurers in search of gold. The player is stuck in a temple and has to explore the temple for escape routes. The game has three levels, where level one focuses on DAC, level two focuses on ACL and the last level is for MAC. The player has to explore the temple and gain knowledge on targeted concepts to unlock the gate to the next level. Three in-game assessments have been implemented to provide immediate feedback for students. The UI Accessibility Plugin (UAP) is used to make the game accessible to visually impaired players. To scientifically measure the effectiveness of the game, we developed pre-test, post-test, survey, and focus group protocols. The game has been used in the Operating Systems class as a homework assignment at North Carolina A&T State University in spring 2020. This poster will present the game design and development process, the detailed evaluation plan, and our initial classroom experience. This portable and self-contained game will make it easy to share with other faculty engaged in cyber security teaching and research.

Ensuring security and privacy of IOT devices and the associated/ dependent complex and critical systems is certainly a major concern, especially after proliferation of IoT devices in variety of domains in current era. A considerable level of security can be achieved in these systems using the techniques of Role Based Access Control (RBAC). In contrast to Discretionary Access Control (DAC) where personal identity of the owner/ user matters, RBAC grants access permissions on the basis of roles of the user. Due to the inherent complexity associated with ensuring security in IoT devices and related systems/ services, a level of abstraction is required in the development process, in order to better understand and develop the system accordingly by integrating all the security aspects. This level of abstraction can be achieved by developing the system as per the concepts of Model Driven Development (MDD). In this paper, techniques of Model Driven Architecture (MDA)/ MDD has been used to propose such a Framework/ Meta-Model, which ensures RBAC in order to access the services associated with IoT devices. The proposed Meta-Model can be further extended for the model-based development and automation of such a system that ensure RBAC for IoT devices. Validity of proposed Meta-Model has been proved by creating an M1 level Instance Model of a real-world case study. Results prove, that the proposed Meta-Model is capable to be transformed into a reliable system that ensures RBAC in IoT devices.

The author considers the Internet of Things security problems, namely, the organization of secure access control when using the MQTT protocol. Security mechanisms and methods that are employed or supported by the MQTT protocol have been analyzed. Thus, the protocol employs authentication by the login and password. In addition, it supports cryptographic processing over transferring data via the TLS protocol. Third-party services on OAuth protocol can be used for authentication. The authorization takes place by configuring the ACL-files or via third-party services and databases. The author suggests a device discretionary access control model of machine-to-machine interaction under the MQTT protocol, which is based on the HRU-model. The model entails six operators: the addition and deletion of a subject, the addition and deletion of an object, the addition and deletion of access privileges. The access control model is presented in a form of an access matrix and has three types of privileges: read, write, ownership. The model is composed in a way that makes it compatible with the protocol of a widespread version v3.1.1. The available types of messages in the MQTT protocol allow for the adjustment of access privileges. The author considered an algorithm with such a service data unit build that the unit could easily be distinguished in the message body. The implementation of the suggested model will lead to the minimization of administrator’s involvement due to the possibility for devices to determine access privileges to the information resource without human involvement. The author suggests recommendations for security policies, when organizing an informational exchange in accordance with the MQTT protocol.

The usage of the web based social networks is growing day by day. Our daily life has become dependent on the usage of these social networking applications (apps). These apps allow the people of different ages to share their ideas and remain connected to the people they like to connect with through the medium of internet. There are several web based social networking apps such as Instagram, Twitter, LinkedIn, and Facebook. Facebook has experienced the rapid growth in the number of users in last few years. The access control paradigm of Facebook is different from the way it is generally being provided. The access control is mainly defined through: Role based access control, Trust Management System, Discretionary Access Control. Web based social networks offer attractive means for interaction and communication; on the other hand they also raise privacy and security concerns. There are risks related to the privacy of the users attached to the usage of web based social networks as most of the users accept the privacy and access control policies of such apps without understanding the threat associated with the same. We try to explore some of the threats related to the privacy and access control of web based social network that helps the users to keep their profile safe and avoid any type of data breach.

Traditional discretionary access control (DAC) or mandatory access control (MAC) is not quite effective for remote environment. General role-based access control (RBAC) also has its limitations to control access for applications like remote healthcare due to its static nature. Design of effective access control model is indeed a big challenge for such applications. Fine-grained access control logic capable of adapting changes based on run-time information needs to be considered to meet the requirements of remote healthcare scenarios. In this work, an adaptive access control model is proposed keeping in compliance with state–of-the-art scenario towards ensuring quality of context and trust relationship between owners and users. It focuses on inter-component relationship, where phases are executed either in online or in offline mode to avoid performance bottleneck. Adaptive binding is integrated with application specific workflows. Workflow net models for different scenarios of medical kiosk-based rural healthcare are analyzed to validate proposed access control logic at design time that can reduce the possibility of major faults at run time. Our proposed work supports formal analysis and verification using Workflow Petri Net Designer (WoPeD) tool. Comparative analysis shows how proposed access control model advances the state of art.

A system and related methods for providing greater security and control over access to classified files and documents and other forms of sensitive information based upon a multi-user, multi-modality permission strategy centering on organizational structure, thereby making authentication strategy unpredictable so to significantly reduce the risk of exploitation. Based on the sensitivity or classification of the information being requested by a user, approvers are selected dynamically based on the work environment, e.g., mobility, use of the computing device seeking access, authentication factors under applicable environmental settings, access policy, and the like.

In software-defined networks (SDN), most controllers do not have an established control function for endpoint users and access terminals to access network, which may lead to many attacks. In order to address the problem of security check on access terminals, a secure trusted access method in SDN is designed and implemented in this paper. The method includes an access architecture design and a security access authentication protocol. The access architecture combines the characteristics of the trusted access technology and SDN architecture, and enhances the access security of SDN. The security access authentication protocol specifies the specific structure and implementation of data exchange in the access process. The architecture and protocol implemented in this paper can complete the credibility judgment of the access device and user's identification. Furthermore, it provides different trusted users with different network access permissions. Experiments show that the proposed access method is more secure than the access method that is based on IP address, MAC address and user identity authentication only, thus can effectively guarantee the access security of SDN.

Attribute-based access control (ABAC) is a promising alternative to traditional models of access control (i.e., discretionary access control (DAC), mandatory access control (MAC), and role-based access control (RBAC)) that is drawing attention in both recent academic literature and industry application. However, formalization of a foundational model of ABAC and large scale adoption is still in its infancy. The relatively recent emergence of ABAC still leaves a number of problems unexplored. Issues like delegation, administration, auditability, scalability, hierarchical representations, and the like, have been largely ignored or left to future work. This article provides a basic introduction to ABAC and a comprehensive review of recent research efforts toward developing formal models of ABAC. A taxonomy of ABAC research is presented and used to categorize and evaluate surveyed articles. Open problems are identified based on the shortcomings of the reviewed works and potential solutions discussed.

How should applications legitimately requiring access to sensitive resources to carry out their functionality be granted access to those resources? The answer to this question depends on users. This article introduces user-driven access control, an alternate permission model that adheres to the principle of least privilege while reducing the burden on users to make explicit permission decisions.

As the technology of attribute-based access control (ABAC) matures and begins to supplant earlier models such as role-based or discretionary access control, it becomes necessary to convert from already deployed access control systems to ABAC. Several variations of this general problem can be defined, some of which have been studied by researchers. In particular the ABAC policy mining problem assumes that attribute values for various entities such as users and objects in the system are given, in addition to the authorization state, from which the ABAC policy needs to be discovered. In this paper, we formalize the ABAC RuleSet Existence problem in this context and develop an algorithm and complexity analysis for its solution. We further introduce the notion of ABAC RuleSet Infeasibility Correction along with an algorithm for its solution.

Access control is a security technique that specifies which users can access particular resources in a computing environment. Over the years, numerous access control models have been developed to address various aspects of computer security. In this paper, we focus on a modern approach, attribute-based access control (ABAC), which has been proposed in order to overcome limitations of traditional models: discretionary access control (DAC), mandatory access control (MAC) and role-based access control (RBAC). The work on integrating access control mechanisms in semantic web technologies is developing into two directions: (1) to use semantic web technologies for modeling and analyzing access control policies and (2) to protect knowledge encoded in an ontology. In this paper we focus on the first issue and investigate how ABAC can be integrated into ontology languages.

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.

Privilege separation systems that are implemented in applications such as Chromium and OpenSSH Dae- mon(SSHD) are complex, cumbersome because they have to be built on top of traditional Access Control List(ACL) systems. Properties such as least privilege operations along with effective solutions to problems that plague ACL based implementations, such as the Confused Deputy problem makes Capabilities much more capable when compared with the current Mandatory Access Control (MAC)/ Discretionary Access Control(DAC) systems in use within the POSIX systems for implementing privilege separated applications. While some work has been done on integrating a capability system into Linux, the final implementation provided solution for a specific subset of problems that a typical Capability based systems addresses. We provide a kernel module that enhances the Linux File Descriptors (FD) with revocation property, that while providing as a starting point for future refinements and improvements for creating a Capability system, also provides sufficient advantages to existing work flows that involves privilege separation.

In many organizations, it is vital to protect sensitive and confidential data in today’s digital world. For this case such information is made as an open database system; businesses can face legal or financial ramifications. According to the various nature and structures of the organizations, they may not have the same defense and interrelated communities which consist of military services, bank, and other intelligence organizations. All kinds of organizations must set policies to systematically and consistently categorize their data security from theft and threats. There are many types of access control mechanisms depending on the nature of organization such as mandatory access control (MAC), role-based access control (RBAC), and discretionary access control (DAC). This proposed framework focuses on the common threats that can face in the multilevel organizations, the security mechanisms to be considered, and how to secure a database. Multilevel security system allows users with different clearance levels, authorization, and need to know ability to process information in the same system. Moreover, the technical security controls such as user authentication, file access authorization, data encryption, and privacy controls for each user are applied for this framework. The proposed system will present the implementation of effective security framework for multilevel organizations using Strict Integrity Policy by labeling clearances levels to system’s users and classification levels to system’s stored data.