Graphical Interface for Ontology Mapping with Application to Access Control

We describe a method that centrally manages Attribute-Based Access Control (ABAC) policies and locally computes and enforces decisions regarding those policies for protection of resource repositories in host systems using their native Access Control List (ACL) mechanisms. The method is founded on the expression of an ABAC policy that conforms to the access control rules of an enterprise and leverages the ABAC policy expression by introducing representations of local host repositories into the ABAC policy expression as objects or object attributes. Repositories may be comprised of individual files, directories, or other resources that require protection. The method further maintains a correspondence between the ABAC representations and repositories in local host systems. The method also leverages an ability to conduct policy analytics in such a way as to formulate ACLs for those representations in accordance with the ABAC policy and create ACLs on repositories using the ACLs of their corresponding representations. As the ABAC policy configuration changes, the method updates the ACLs on affected representations and automatically updates corresponding ACLs on local repositories. Operationally, users attempt to access resources in local host systems, and the ABAC policy is enforced in those systems in terms of their native ACLs.

In this disseration we propose semi-automated top-down policy engineering approaches for attribute-based access control (ABAC) development. Further, we propose a hybrid ABAC policy engineering approach to combine the benefits and address the shortcomings of both top-down and bottom-up approaches. In particular, we propose three frameworks: (i) ABAC attributes extraction, (ii) ABAC constraints extraction, and (iii) hybrid ABAC policy engineering. Attributes extraction framework comprises of five modules that operate together to extract attributes values from natural language access control policies (NLACPs); map the extracted values to attribute keys; and assign each key-value pair to an appropriate entity. For ABAC constraints extraction framework, we design a two-phase process to extract ABAC constraints from NLACPs. The process begins with the identification phase which focuses on identifying the right boundary of constraint expressions. Next is the normalization phase, that aims at extracting the actual elements that pose a constraint. On the other hand, our hybrid ABAC policy engineering framework consists of 5 modules. This framework combines top-down and bottom-up policy engineering techniques to overcome the shortcomings of both approaches and to generate policies that are more intuitive and relevant to actual organization policies. With this, we believe that our work takes essential steps towards a semi-automated ABAC policy development experience.

Access control policies are crucial for establishing a secure access control system and are fundamentally based on access control models such as attribute-based access control (ABAC). Moreover, the execution of business process instances is generally recorded within an event log. It is essential to ensure conformance with ABAC policies for the event log at the time of post-execution. To conduct conformance testing of ABAC policies in business process event logs, formalizing these ABAC policies is necessary. However, the formalization is typically carried out manually, which leads to inefficiencies, low maintainability, a high likelihood of errors, and difficulty in detecting the errors. Also, there has been a notable lack of an access control metamodel to support the formalization and conformance testing of ABAC policies, as well as insufficient attention to constructing ABAC policies from existing process logs. This paper presents a model-driven workflow for significantly automating the formalization and conformance testing of ABAC policies in process logs. By leveraging a novel ABAC metamodel and its reusable patterns, the approach addresses the aforementioned issues, demonstrating effectiveness through experiments on a real-world process log.

Access control policies are dynamic in nature, and therefore require frequent updates to synchronize with the latest organizational security requirements. As these updates are handled, it is important that all user access requests be answered contemporaneously and correctly without any interruption or delay. In this paper, considering the context of Attribute Based Access Control (ABAC), we propose an approach that is capable of immediately materializing any update to the policy and ensuring that it is taken into account for any subsequent access requests. One possibility is to update the policy based on the incoming changes through ABAC policy mining techniques. However, it turns out that no existing mining approach can offer correct enforcement of policies when access requests are entertained during the updates. We provide a formal proof for this surprising result and then propose an approach called δwOP that does not suffer from this problem. Essentially, δwOP keeps track of the needed information from updates and uses this in conjunction with the existing ABAC policy rules to make access decisions. We present the complexity analysis as well as a comprehensive experimental evaluation to demonstrate the efficacy of the proposed approach for different types of changes.

[formula omitted]: A blockchain-based secure access control management for the Internet of Things

Chapter 23 - Policies, Access Control, and Formal Methods

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.

In this paper, a variety of cloud service combinations is used to form the control core of a smart home, realize data forwarding, storage, and analysis in the cloud, and complete the remote management of smart home devices. This paper studies the secure access control of smart home data combined with the blockchain technology and password technology to realize the secure and efficient access control of smart home data. The system can achieve the goal of independent research and development. Aiming at the problem that the access control of a smart home is generally managed by third‐party authorized institutions and there is an unauthorized access, a blockchain‐based smart home (BSH) access control scheme is proposed. The scheme extends the attribute‐based access control model (ABAC) and applies the blockchain technology to the smart home ABAC model to realize fine‐grained access control. In the scheme, the resource provider first publishes the access control policy of the resource to the blockchain. If the resource visitor wants to access the resource, he needs to submit an access request to the blockchain and use an SM2 threshold signature to process the transaction proposal. The endorsement peer node in the blockchain runs the access control policy smart contract to decide whether to grant access rights. This scheme can ensure that resource providers can participate in all the processes of access control and avoid the risk of unauthorized access caused by the centralized management of the third party. Finally, the simulation experiment is carried out on the Hyperledger Fabric alliance chain development platform. The results show that the BSH access control scheme has good applicability in the smart home scenario.

Traditional access control models often assume that the entity enforcing access control policies is also the owner of data and resources. This assumption no longer holds when data is outsourced to a third-party storage provider, such as the cloud. Existing access control solutions mainly focus on preserving confidentiality of stored data from unauthorized access and the storage provider. However, in this setting, access control policies as well as users’ access patterns also become privacy sensitive information that should be protected from the cloud. We propose a two-level access control scheme that combines coarse-grained access control enforced at the cloud, which provides acceptable communication overhead and at the same time limits the information that the cloud learns from his partial view of the access rules and the access patterns, and fine-grained cryptographic access control enforced at the user’s side, which provides the desired expressiveness of the access control policies. Our solution handles both read and write access control.KeywordsAccess ControlAccess PatternCloud ProviderData OwnerAccess Control PolicyThese 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.

Nowadays, cloud-based storage systems play a vital role in IoT data storage, processing, and sharing. Despite its contribution, the current cloud-based architecture may cause severe data leakage or jeopardize user privacy. Meanwhile, the cloud-based architecture heavily relies on a trusted third-party auditor (TPA) and runs in a centralized control manner. However, the TPA may not be a completely trustworthy entity, and a single point of failure might cause the centralized system to collapse. Fortunately, with the advent of blockchain technology, the decentralized storage model has gained popularity. A decentralized storage system successfully eradicates the rule of TPA, solves the problem of a single point of failure, and has many advantages over a centralized control architecture, such as low storage prices and high throughput. This study offers a blockchain-based decentralized distributed storage and sharing scheme that provides end-to-end encryption and fine-grained access control. In our proposed IoTChain model, fine-grained permission is based on attribute-based access control (A-BAC) policy by employing the Ethereum blockchain as an auditable access control layer. Smart contracts are tailored for the IoTChain model, which combines the Ethereum blockchain and the interplanetary file system (IPFS). We used an advanced encryption standard (AES) for encryption and the elliptic curve Diffie-Hellman key exchange protocol for secret key sharing between data owners and users. Also, the proof-of-work (PoW) consensus mechanism is replaced with a proof-of-authority (PoA) to minimize system transaction cost and boost system throughput. Additionally, our solution has been tested on the Ethereum official test network Rinkeby, and the results demonstrate that our approach is realistic and economical on the IoT data.

Mobile edge computing (MEC) technology is widely used for real‐time and bandwidth‐intensive services, but its underlying heterogeneous architecture may lead to a variety of security and privacy issues. Blockchain provides novel solutions for data security and privacy protection in MEC. However, the scalability of traditional blockchain is difficult to meet the requirements of real‐time data processing, and the consensus mechanism is not suitable for resource‐constrained devices. Moreover, the access control of MEC data needs to be further improved. Given the above problems, a data privacy protection model based on sharding blockchain and access control is designed in this paper. First, a privacy‐preserving platform based on a sharding blockchain is designed. Reputation calculation and improved Proof‐of‐Work (PoW) consensus mechanism are proposed to accommodate resource‐constrained edge devices. The incentive mechanism with rewards and punishments is designed to constrain node behavior. A reward allocation algorithm is proposed to encourage nodes to actively contribute to obtaining more rewards. Second, an access control strategy using ciphertext policy attribute‐based encryption (CP‐ABE) and RSA is designed. A smart contract is deployed to implement the automatic access control function. The InterPlanetary File System is introduced to alleviate the blockchain storage burden. Finally, we analyze the security of the proposed privacy protection model and statistics of the GAS consumed by the access control policy. The experimental results show that the proposed data privacy protection model achieves fine‐grained control of access rights, and has higher throughput and security than traditional blockchain.

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.

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.

PurposeThis paper aims to manage access control tasks to satisfy the user privacy needs of online information resources according to social relations and tags.Design/methodology/approachThe study proposes a method for access control management in the online social context. The proposed method includes the access control policy management process, metadata of access control policies, the data of ontologies, tags, and social relations, and conflict detection rules.FindingsOnline information sharing and hiding, which needs to consider social relations and mentioned topics, is a unique context and needs a novel access control mechanism. Ontologies are powerful and expressive enough to identify conflicts in access control policies. The paper provides a method using ontologies to control the access control activities based on social relations and tags on web content. The effectiveness of the method's conflict detection rules is validated through several scenarios.Research limitations/implicationsTo make the proposed method suitable for widespread usage, further work is required to develop an access control policy specification and conflict detection tool. The proposed method introduces relatively novel usage scenarios, which consider social relationships, and tags compared with existing access control methods for online information sharing.Practical implicationsThe proposed access control mechanism can be integrated into existing web sites. Online users can use this method to share information more easily than at present.Originality/valueThe method enables flexible access control in social contexts and handles unavoidable conflicts. It also opens the way to new access control scenarios in online social activities. The method can be used to keep secrets hidden from selected people.

This thesis describes a data provenance framework and other associated frameworks for utilizing provenance for data quality and reproducibility. We first identify the requirements for the design of a comprehensive provenance framework which can be applicable to various applications, supports a rich set of provenance metadata, and is interoperable with other provenance management systems. We then design and develop a provenance framework, called SimP, addressing such requirements. Next, we present four prominent applications and investigate how provenance data can be beneficial to such applications. The first application is the quality assessment of access control policies. Towards this, we design and implement the ProFact framework which uses provenance techniques for collecting comprehensive data about actions which were either triggered due to a network context or a user (i.e., a human or a device) action. Provenance data are used to determine whether the policies meet the quality requirements. ProFact includes two approaches for policy analysis: structure-based and classification-based. For the structure-based approach, we design tree structures to organize and assess the policy set efficiently. For the classification-based approach, we employ several classification techniques to learn the characteristics of policies and predict their quality. In addition, ProFact supports policy evolution and the assessment of its impact on the policy quality. The second application is workflow reproducibility. Towards this, we implement ProWS which is a provenance-based architecture for retrieving workflows. Specifically, ProWS transforms data provenance into workflows and then organizes data into a set of indexes to support efficient querying mechanisms. ProWS supports composite queries on three types of search criteria: keywords of workflow tasks, patterns of workflow structure, and metadata about workflows (e.g., how often a workflow was used). The third application is the access control policy reproducibility. Towards this, we propose a novel framework, Polisma, which generates attribute-based access control policies from data, namely from logs of historical access requests and their corresponding decisions. Polisma combines data mining, statistical, and machine learning techniques, and capitalizes on potential context information obtained from external sources (e.g., LDAP directories) to enhance the learning process. The fourth application is the policy reproducibility by utilizing knowledge and experience transferability. Towards this, we propose a novel framework, FLAP, which transfer attribute-based access control policies between different parties in a collaborative environment, while considering the challenges of minimal sharing of data and support policy adaptation to address conflict. All frameworks are evaluated with respect to performance and accuracy.