Secure data sharing and processing in heterogeneous clouds

The extensive cloud adoption among the European Public Sector Players empowered them to own and operate a range of cloud infrastructures. These deployments vary both in the size and capabilities, as well as in the range of employed technologies and processes. The public sector, however, lacks the necessary technology to enable effective, interoperable and secure integration of a multitude of its computing clouds and services. In this work we focus on the federation of private clouds and the approaches that enable secure data sharing and processing among the collaborating infrastructures and services of public entities. We investigate the aspects of access control, data and security policy languages, as well as cryptographic approaches that enable fine-grained security and data processing in semi-trusted environments. We identify the main challenges and frame the future work that serve as an enabler of interoperability among heterogeneous infrastructures and services. Our goal is to enable both security and legal conformance as well as to facilitate transparency, privacy and effectivity of private cloud federations for the public sector needs. © 2015 The Authors

Administration of access control in information systems using URBAC model

Since the value of information is constantly growing more and more businesses are in need for information system to aid them with information gathering and processing. The most important issue that arises here is how to ensure safety of this data that may be held on servers, personal computers or PDAs. This is where access control comes in. The main role of access control is to ensure that no unauthorized user will be able to gain access to resources and be able to copy or modify them. The paper deals with the process of access control administration in information systems with the use of usage role-based control approach. The presented process is based on the role engineering concept that includes the creation of security schema of access control divided between two actors - application/system developer and security administrator. They realize their tasks during two main phases that allow to define the complete access control schema for information systems of an organization

AN OBLIGATION MODEL FOR USAGE CONTROL

ABSTRACT How to control the access and usage of digital resources is one of the most important issues in computer security nowadays. Among them, how to control the resources when they have been passed to the client-side is a research hot spot. The Usage Control Model (UCON) has been proposed to solve this problem. In this research, we focus on one core component of the UCON model, the obligation. We propose a new obligation model to solve the problems the current ones can not deal with, especially for post-obligation. We also offer two testing scenarios, propose an architecture for a prototype based on the proposed model and apply the scenarios to the prototype architecture for proof-of-concept

BlueSky: Combining Task Planning and Activity-Centric Access Control for Assistive Humanoid Robots

In the not too distant future, assistive humanoid robots will provide versatile assistance for coping with everyday life. In their interactions with humans, not only safety, but also security and privacy issues need to be considered. In this Blue Sky paper, we therefore argue that it is time to bring task planning and execution as a well-established field of robotics with access and usage control in the field of security and privacy closer together. In particular, the recently proposed activity-based view on access and usage control provides a promising approach to bridge the gap between these two perspectives. We argue that humanoid robots provide for specific challenges due to their task-universality and their use in both, private and public spaces. Furthermore, they are socially connected to various parties and require policy creation at runtime due to learning. We contribute first attempts on the architecture and enforcement layer as well as on joint modeling, and discuss challenges and a research roadmap also for the policy and objectives layer. We conclude that the underlying combination of decentralized systems\u27 and smart environments\u27 research aspects provides for a rich source of challenges that need to be addressed on the road to deployment

Access Control in Industrial Internet of Things

The Industrial Internet of Things (IIoT) is an ecosystem that consists of - among others - various networked sensors and actuators, achieving mainly advancements related with lowering production costs and providing workflow flexibility. Introducing access control in such environments is considered to be challenging, mainly due to the variety of technologies and protocols in IIoT devices and networks. Thus, various access control models and mechanisms should be examined, as well as the additional access control requirements posed by these industrial environments. To achieve these aims, we elaborate on existing state-of-the-art access control models and architectures and investigate access control requirements in IIoT, respectively. These steps provide valuable indications on what type of an access control model and architecture may be beneficial for application in the IIoT. We describe an access control architecture capable of achieving access control in IIoT using a layered approach and based on existing virtualization concepts (e.g., the cloud). Furthermore, we provide information on the functionality of the individual access control related components, as well as where these should be placed in the overall architecture. Considering this research area to be challenging, we finally discuss open issues and anticipate these directions to provide interesting multi-disciplinary insights in both industry and academia

Data-centric access control for cloud computing

© 2016 ACM. The usual approach to security for cloud-hosted applications is strong separation. However, it is often the case that the same data is used by different applications, particularly given the increase in data-driven (big data' and IoT) applications. We argue that access control for the cloud should no longer be application-specific but should be data-centric, associated with the data that can ow between applications. Indeed, the data may originate outside cloud services from diverse sources such as medical monitoring, environmental sensing etc. Information Flow Control (IFC) potentially offers data-centric, system-wide data access control. It has been shown that IFC can be provided at operating system level as part of a PaaS offering, with an acceptable overhead. In this paper we consider how IFC can be integrated with application-specific access control, transparently from application developers, while building from simple IFC primitives, access control policies that align with the data management obligations of cloud providers and tenants.This work was supported by the UK EPSRC grant EP/ K011510 CloudSafetyNet. We acknowledge the support of Microsoft through the Microsoft Cloud Computing Research Centre

A Framework for an Adaptive Early Warning and Response System for Insider Privacy Breaches

Organisations such as governments and healthcare bodies are increasingly responsible for managing large amounts of personal information, and the increasing complexity of modern information systems is causing growing concerns about the protection of these assets from insider threats. Insider threats are very difficult to handle, because the insiders have direct access to information and are trusted by their organisations. The nature of insider privacy breaches varies with the organisation’s acceptable usage policy and the attributes of an insider. However, the level of risk that insiders pose depends on insider breach scenarios including their access patterns and contextual information, such as timing of access. Protection from insider threats is a newly emerging research area, and thus, only few approaches are available that systemise the continuous monitoring of dynamic insider usage characteristics and adaptation depending on the level of risk. The aim of this research is to develop a formal framework for an adaptive early warning and response system for insider privacy breaches within dynamic software systems. This framework will allow the specification of multiple policies at different risk levels, depending on event patterns, timing constraints, and the enforcement of adaptive response actions, to interrupt insider activity. Our framework is based on Usage Control (UCON), a comprehensive model that controls previous, ongoing, and subsequent resource usage. We extend UCON to include interrupt policy decisions, in which multiple policy decisions can be expressed at different risk levels. In particular, interrupt policy decisions can be dynamically adapted upon the occurrence of an event or over time. We propose a computational model that represents the concurrent behaviour of an adaptive early warning and response system in the form of statechart. In addition, we propose a Privacy Breach Specification Language (PBSL) based on this computational model, in which event patterns, timing constraints, and the triggered early warning level are expressed in the form of policy rules. The main features of PBSL are its expressiveness, simplicity, practicality, and formal semantics. The formal semantics of the PBSL, together with a model of the mechanisms enforcing the policies, is given in an operational style. Enforcement mechanisms, which are defined by the outcomes of the policy rules, influence the system state by mutually interacting between the policy rules and the system behaviour. We demonstrate the use of this PBSL with a case study from the e-government domain that includes some real-world insider breach scenarios. The formal framework utilises a tool that supports the animation of the enforcement and policy models. This tool also supports the model checking used to formally verify the safety and progress properties of the system over the policy and the enforcement specifications

Assured information sharing for ad-hoc collaboration

Collaborative information sharing tends to be highly dynamic and often ad hoc among organizations. The dynamic natures and sharing patterns in ad-hoc collaboration impose a need for a comprehensive and flexible approach to reflecting and coping with the unique access control requirements associated with the environment. This dissertation outlines a Role-based Access Management for Ad-hoc Resource Shar- ing framework (RAMARS) to enable secure and selective information sharing in the het- erogeneous ad-hoc collaborative environment. Our framework incorporates a role-based approach to addressing originator control, delegation and dissemination control. A special trust-aware feature is incorporated to deal with dynamic user and trust management, and a novel resource modeling scheme is proposed to support fine-grained selective sharing of composite data. As a policy-driven approach, we formally specify the necessary pol- icy components in our framework and develop access control policies using standardized eXtensible Access Control Markup Language (XACML). The feasibility of our approach is evaluated in two emerging collaborative information sharing infrastructures: peer-to- peer networking (P2P) and Grid computing. As a potential application domain, RAMARS framework is further extended and adopted in secure healthcare services, with a unified patient-centric access control scheme being proposed to enable selective and authorized sharing of Electronic Health Records (EHRs), accommodating various privacy protection requirements at different levels of granularity

SoNeUCONADM: the administrative model for SoNeUCONABC usage control model

The popularity of Web Based Social Networks (WBSNs) encourages their enhancement. Many WBSN data is considered personal data and access control management plays a key role in this regard. The point is not only to manage access control but to determine how administration should be performed. Based on SoNeUCONABC, an expressive usage control model that allows fine-grained access control management, this paper presents SoNeUCONADM, the complementary administrative model. Based on a pair of related and popular administrative models, the evaluation proves the completeness of SoNeUCONADM

Towards Practical Access Control and Usage Control on the Cloud using Trusted Hardware

Cloud-based platforms have become the principle way to store, share, and synchronize files online. For individuals and organizations alike, cloud storage not only provides resource scalability and on-demand access at a low cost, but also eliminates the necessity of provisioning and maintaining complex hardware installations. Unfortunately, because cloud-based platforms are frequent victims of data breaches and unauthorized disclosures, data protection obliges both access control and usage control to manage user authorization and regulate future data use. Encryption can ensure data security against unauthorized parties, but complicates file sharing which now requires distributing keys to authorized users, and a mechanism that prevents revoked users from accessing or modifying sensitive content. Further, as user data is stored and processed on remote ma- chines, usage control in a distributed setting requires incorporating the local environmental context at policy evaluation, as well as tamper-proof and non-bypassable enforcement. Existing cryptographic solutions either require server-side coordination, offer limited flexibility in data sharing, or incur significant re-encryption overheads on user revocation. This combination of issues are ill-suited within large-scale distributed environments where there are a large number of users, dynamic changes in user membership and access privileges, and resources are shared across organizational domains. Thus, developing a robust security and privacy solution for the cloud requires: fine-grained access control to associate the largest set of users and resources with variable granularity, scalable administration costs when managing policies and access rights, and cross-domain policy enforcement. To address the above challenges, this dissertation proposes a practical security solution that relies solely on commodity trusted hardware to ensure confidentiality and integrity throughout the data lifecycle. The aim is to maintain complete user ownership against external hackers and malicious service providers, without losing the scalability or availability benefits of cloud storage. Furthermore, we develop a principled approach that is: (i) portable across storage platforms without requiring any server-side support or modifications, (ii) flexible in allowing users to selectively share their data using fine-grained access control, and (iii) performant by imposing modest overheads on standard user workloads. Essentially, our system must be client-side, provide end-to-end data protection and secure sharing, without significant degradation in performance or user experience. We introduce NeXUS, a privacy-preserving filesystem that enables cryptographic protection and secure file sharing on existing network-based storage services. NeXUS protects the confidentiality and integrity of file content, as well as file and directory names, while mitigating against rollback attacks of the filesystem hierarchy. We also introduce Joplin, a secure access control and usage control system that provides practical attribute-based sharing with decentralized policy administration, including efficient revocation, multi-domain policies, secure user delegation, and mandatory audit logging. Both systems leverage trusted hardware to prevent the leakage of sensitive material such as encryption keys and access control policies; they are completely client-side, easy to install and use, and can be readily deployed across remote storage platforms without requiring any server-side changes or trusted intermediary. We developed prototypes for NeXUS and Joplin, and evaluated their respective overheads in isolation and within a real-world environment. Results show that both prototypes introduce modest overheads on interactive workloads, and achieve portability across storage platforms, including Dropbox and AFS. Together, NeXUS and Joplin demonstrate that a client-side solution employing trusted hardware such as Intel SGX can effectively protect remotely stored data on existing file sharing services