Biblio

Enhancing trust among service providers and end-users with respect to data protection is an urgent matter in the growing information society. In response, CREDENTIAL proposes an innovative cloud-based service for storing, managing, and sharing of digital identity information and other highly critical personal data with a demonstrably higher level of security than other current solutions. CREDENTIAL enables end-to-end confidentiality and authenticity as well as improved privacy in cloud-based identity management and data sharing scenarios. In this paper, besides clarifying the vision and use cases, we focus on the adoption of CREDENTIAL. Firstly, for adoption by providers, we elaborate on the functionality of CREDENTIAL, the services implementing these functions, and the physical architecture needed to deploy such services. Secondly, we investigate factors from related research that could be used to facilitate CREDENTIAL's adoption and list key benefits as convincing arguments.

The use of cloud computing and cloud federations has been the focus of studies in the last years. Many of these infrastructures delegate user authentication to Identity Providers. Once these services are available through the Internet, concerns about the confidentiality of user credentials and attributes are high. The main focus of this work is the security of the credentials and user attributes in authentication infrastructures, exploring secret sharing techniques and using cloud federations as a base for storing this information.

In cloud storage, remote data integrity checking is considered as a crucial technique about data owners who upload enormous data to cloud server provider. A majority of the existing remote data integrity checking protocols rely on the expensive public key infrastructure. In addition, the verification of certificates needs heavy computation and communication cost. Meanwhile, the existing some protocols are not secure under the quantum computer attacks. However, lattice-based constructed cryptography can resist quantum computer attacks and is fairly effective, involving matrix-matrix or matrix-vector multiplications. So, we propose an identity-based remote data integrity checking protocol from lattices, which can eliminate the certificate management process and resist quantum computer attacks. Our protocol is completeness and provably secure based on the hardness small integer solution assumption. The presented scheme is secure against cloud service provider attacks, and leaks no any blocks of the stored file to the third party auditor during verification stage, namely the data privacy against the curiosity third party auditor attacks. The cloud service provider attack includes lost attack and tamper attack. Furthermore, the performance analysis of some protocols demonstrate that our protocol of remote data integrity checking is useful and efficient.

Efficient trust management between nodes in a huge network is an essential requirement in modern networks. This work shows few generic primitive protocols for creating a trusted link between nodes by deploying unclonable physical tokens as Secret Unknown Ciphers. The proposed algorithms are making use of the clone-resistant physical identity of each participating node. Several generic node authentication protocols are presented. An intermediate node is shown to be usable as a mediator to build trust without having influence on the resulting security chain. The physical clone-resistant identities are using our early concept of Secret Unknown Cipher (SUC) technique. The main target of this work is to show the particular and efficient trust-chaining in large networks when SUC techniques are involved.

In contrast to electronic travel documents (e.g. ePassports), the standardisation of breeder documents (e.g. birth certificates), regarding harmonisation of content and contained security features is in statu nascendi. Due to the fact that breeder documents can be used as an evidence of identity and enable the application for electronic travel documents, they pose the weakest link in the identity life cycle and represent a security gap for identity management. In this work, we present a cost efficient way to enhance the long-term security of breeder documents by utilizing blockchain technology. A conceptual architecture to enhance breeder document long-term security and an introduction of the concept's constituting system components is presented. Our investigations provide evidence that the Bitcoin blockchain is most suitable for breeder document long-term security.

Identities are known as the most sensitive information. With the increasing number of connected objects and identities (a connected object may have one or many identities), the computing and communication capabilities improved to manage these connected devices and meet the needs of this progress. Therefore, new IoT Identity Management System (IDMS) requirements have been introduced. In this work, we suggest an IDMS approach to protect private information and ensures domain change in IoT for mobile clients using a personal authentication device. Firstly, we present basic concepts, existing requirements and limits of related works. We also propose new requirements and show our motivations. Next, we describe our proposal. Finally, we give our security approach validation, perspectives, and some concluding remarks.

Swarms of embedded devices provide new challenges for privacy and security. We propose Permissioned Blockchains as an effective way to secure and manage these systems of systems. A long view of blockchain technology yields several requirements absent in extant blockchain implementations. Our approach to Permissioned Blockchains meets the fundamental requirements for longevity, agility, and incremental adoption. Distributed Identity Management is an inherent feature of our Permissioned Blockchain and provides for resilient user and device identity and attribute management.

For over 50 years, the password has been a frequently used, yet relatively ineffective security mechanism for user authentication. The ubiquitous smartphone is a compact suite of sensors, computation, and network connectivity that corporations are beginning to embrace under BYOD (bring your own device). In this paper, we hypothesize that each of us has a unique “walking signature” that a smartphone can recognize and use to provide passive, continuous authentication. This paper describes the exploratory data analysis of a small, cross-sectional, empirical study of users' walking signatures as observed by a smartphone. We then describe an identity management system that could use a walking signature as a means to passively and continuously authenticate a user and manage complex passwords to improve security.

In the 21st century, each country must make decisions on how to utilize modern technologies to maximize benefits and minimize repercussions. For example, the United States Department of Defense (DoD) needs to be able to share information efficiently with its allies while simultaneously preventing unwarranted access or attacks. These attacks pose a threat to the national security of the United States, but proper use of the cyberspace provides countless benefits. The aim of this paper is to explore Identity and Access Management (IdAM) technologies that the Department of Defense can use in joint operations with allies that will allow efficient information-sharing and enhance security. To this end, we have created a methodology and a model for evaluating Identity and Access Management technologies that the Department of Defense can use in joint operations with other nations, with a specific focus on Japan and Australia. To evaluate these systems, we employed an approach that incorporates Political, Operational, Economic and Technical (POET) factors. Governance protocols, technological solutions, and political factors were first thoroughly reviewed and then used to construct an evaluation model to formally assess Identity and Access Management alternatives. This model provides systematic guidance on how the Department of Defense can improve their use of Identity and Access Management systems in the future.

Enterprises have recognised the importance of personal mobile devices for business and official use. Employees and consumers have been freely accessing resources and services from their principal organisation and partners' businesses on their mobile devices, to improve the efficiency and productivity of their businesses. This mobile computing-based business model has one major challenge, that of ascertaining and linking users' identities and access rights across business partners. The parent organisation owns all the confidential information about users but the collaborative organisation has to verify users' identities and access rights to allow access to their services and resources. This challenge involves resolving how to communicate users' identities to collaborative organisations without sending their confidential information. Several generic Identity and Access Management (IAM) standards have been proposed, and three have become established standards: Security Assertion Markup Language (SAML), Open Authentication (OAuth), and OpenID Connect (OIDC). Mobile computing and communication have some specific requirements and limitations; therefore, this paper evaluates these IAM standards to ascertain suitable IAM to protect mobile computing and communication. This evaluation is based on the three types of analyses: comparative analysis, suitability analysis and security vulnerability analysis of SAML, OAuth and OIDC.

Access to computer systems and the information held on them, be it commercially or personally sensitive, is naturally, strictly controlled by both legal and technical security measures. One such method is digital identity, which is used to authenticate and authorize users to provide access to IT infrastructure to perform official, financial or sensitive operations within organisations. However, transmitting and sharing this sensitive information with other organisations over insecure channels always poses a significant security and privacy risk. An example of an effective solution to this problem is the Federated Identity Management (FIdM) standard adopted in the cloud environment. The FIdM standard is used to authenticate and authorize users across multiple organisations to obtain access to their networks and resources without transmitting sensitive information to other organisations. Using the same authentication and authorization details among multiple organisations in one federated group, it protects the identities and credentials of users in the group. This protection is a balance, mitigating security risk whilst maintaining a positive experience for users. Three of the most popular FIdM standards are Security Assertion Markup Language (SAML), Open Authentication (OAuth), and OpenID Connect (OIDC). This paper presents an assessment of these standards considering their architectural design, working, security strength and security vulnerability, to cognise and ascertain effective usages to protect digital identities and credentials. Firstly, it explains the architectural design and working of these standards. Secondly, it proposes several assessment criteria and compares functionalities of these standards based on the proposed criteria. Finally, it presents a comprehensive analysis of their security vulnerabilities to aid in selecting an apposite FIdM. This analysis of security vulnerabilities is of great significance because their improper or erroneous deployme- t may be exploited for attacks.

Cloud-centric cognitive cellular networks utilize dynamic spectrum access and opportunistic network access technologies as a means to mitigate spectrum crunch and network demand. However, furnishing a carrier with personally identifiable information for user setup increases the risk of profiling in cognitive cellular networks, wherein users seek secondary access at various times with multiple carriers. Moreover, network access provisioning - assertion, authentication, authorization, and accounting - implemented in conventional cellular networks is inadequate in the cognitive space, as it is neither spontaneous nor scalable. In this paper, we propose a privacy-enhancing user identity management system using blockchain technology which places due importance on both anonymity and attribution, and supports end-to-end management from user assertion to usage billing. The setup enables network access using pseudonymous identities, hindering the reconstruction of a subscriber's identity. Our test results indicate that this approach diminishes access provisioning duration by up to 4x, decreases network signaling traffic by almost 40%, and enables near real-time user billing that may lead to approximately 3x reduction in payments settlement time.

In this paper, we review big data characteristics and security challenges in the cloud and visit different cloud domains and security regulations. We propose using integrated auditing for secure data storage and transaction logs, real-time compliance and security monitoring, regulatory compliance, data environment, identity and access management, infrastructure auditing, availability, privacy, legality, cyber threats, and granular auditing to achieve big data security. We apply a stochastic process model to conduct security analyses in availability and mean time to security failure. Potential future works are also discussed.

Security challenges are the most important obstacles for the advancement of IT-based on-demand services and cloud computing as an emerging technology. Lack of coincidence in identity management models based on defined policies and various security levels in different cloud servers is one of the most challenging issues in clouds. In this paper, a policy- based user authentication model has been presented to provide a reliable and scalable identity management and to map cloud users' access requests with defined polices of cloud servers. In the proposed schema several components are provided to define access policies by cloud servers, to apply policies based on a structural and reliable ontology, to manage user identities and to semantically map access requests by cloud users with defined polices. Finally, the reliability and efficiency of this policy-based authentication schema have been evaluated by scientific performance, security and competitive analysis. Overall, the results show that this model has met defined demands of the research to enhance the reliability and efficiency of identity management in cloud computing environments.

The Internet of Things (IoT) is envisioned to include billions of pervasive and mission-critical sensors and actuators connected to the (public) Internet. This network of smart devices is expected to generate and have access to vast amounts of information, creating unique opportunities for novel applications but, at the same time raising significant privacy and security concerns that impede its further adoption and development. In this paper, we explore the potential of a blockchain-assisted information distribution system for the IoT. We identify key security requirements of such a system and we discuss how they can be satisfied using blockchains and smart contracts. Furthermore, we present a preliminary design of the system and we identify enabling technologies.

The Internet of Things (IoT) will connect not only computers and mobile devices, but it will also interconnect smart buildings, houses, and cities, as well as electrical grids, gas plants, and water networks, automobiles, airplanes, etc. IoT will lead to the development of a wide range of advanced information services that are pervasive, cost-effective, and can be accessed from anywhere and at any time. However, due to the exponential number of interconnected devices, cyber-security in the IoT is a major challenge. It heavily relies on the digital identity concept to build security mechanisms such as authentication and authorization. Current centralized identity management systems are built around third party identity providers, which raise privacy concerns and present a single point of failure. In addition, IoT unconventional characteristics such as scalability, heterogeneity and mobility require new identity management systems to operate in distributed and trustless environments, and uniquely identify a particular device based on its intrinsic digital properties and its relation to its human owner. In order to deal with these challenges, we present a Blockchain-based Identity Framework for IoT (BIFIT). We show how to apply our BIFIT to IoT smart homes to achieve identity self-management by end users. In the context of smart home, the framework autonomously extracts appliances signatures and creates blockchain-based identifies for their appliance owners. It also correlates appliances signatures (low level identities) and owners identifies in order to use them in authentication credentials and to make sure that any IoT entity is behaving normally.

In multi-server environments, remote user authentication is an extremely important issue because it provides authorization while users access their data and services. Moreover, the remote user authentication scheme for multi-server environment has resolved the problem of users needing to manage their different identities and passwords. For this reason, many user authentication schemes for multi-server environments have been proposed in recent years. In 2015, Lu et al. improved Mishra et al.'s scheme, and claimed that their scheme is a more secure and practical remote user authentication for multi-server environments. However, we found that Lu et al.'s scheme is actually insecure and incorrect. In this paper, we demonstrate that their scheme is vulnerable to outsider attack, user forgery attack. We then propose a new biometrics and smart card-based authentication scheme. Finally, we show that our proposed scheme is more secure and supports security properties.

The average computer user is no longer restricted to one device. They may have several devices and expect their applications to work on all of them. A challenge arises when these applications need the cryptographic private key of the devices' owner. Here the device owner typically has to manage keys manually with a "keychain" app, which leads to private keys being transferred insecurely between devices – or even to other people. Even with intuitive synchronization mechanisms, theft and malware still pose a major risk to keys. Phones and watches are frequently removed or set down, and a single compromised device leads to the loss of the owner's private key, a catastrophic failure that can be quite difficult to recover from. We introduce Shatter, an open-source framework that runs on desktops, Android, and Android Wear, and performs key distribution on a user's behalf. Shatter uses threshold cryptography to turn the security weakness of having multiple devices into a strength. Apps that delegate cryptographic operations to Shatter have their keys compromised only when a threshold number of devices are compromised by the same attacker. We demonstrate how our framework operates with two popular Android apps (protecting identity keys for a messaging app, and encryption keys for a note-taking app) in a backwards-compatible manner: only Shatter users need to move to a Shatter-aware version of the app. Shatter has minimal impact on app performance, with signatures and decryption being calculated in 0.5s and security proofs in 14s.

Federated identity providers, e.g., Facebook and PayPal, offer a convenient means for authenticating users to third-party applications. Unfortunately such cross-site authentications carry privacy and tracking risks. For example, federated identity providers can learn what applications users are accessing; meanwhile, the applications can know the users' identities in reality. This paper presents Crypto-Book, an anonymizing layer enabling federated identity authentications while preventing these risks. Crypto-Book uses a set of independently managed servers that employ a (t,n)-threshold cryptosystem to collectively assign credentials to each federated identity (in the form of either a public/private keypair or blinded signed messages). With the credentials in hand, clients can then leverage anonymous authentication techniques such as linkable ring signatures or partially blind signatures to log into third-party applications in an anonymous yet accountable way. We have implemented a prototype of Crypto-Book and demonstrated its use with three applications: a Wiki system, an anonymous group communication system, and a whistleblower submission system. Crypto-Book is practical and has low overhead: in a deployment within our research group, Crypto-Book group authentication took 1.607s end-to-end, an overhead of 1.2s compared to traditional non-privacy-preserving federated authentication.

In this paper, we propose the first identity-based broadcast encryption scheme, which can simultaneously achieves confidentiality and full anonymity against adaptive chosen-ciphertext attacks under a standard assumption. In addition, two further desirable features are also provided: one is fully-collusion resistant which means that even if all users outside of receivers S collude they cannot obtain any information about the plaintext. The other one is stateless which means that the users in the system do not need to update their private keys when the other users join or leave our system. In particular, our scheme is highly efficient, where the public parameters size, the private key size and the decryption cost are all constant and independent to the number of receivers.

This work is motivated by the rapid increase of the number of attacks in computer networks and software engineering. In this paper we study identity snowball attacks and formally prove the correctness of suggested solutions to this type of attack (solutions that are based on the graph reachability reduction) using a proof assistant. We propose a model of an attack graph that captures technical informations about the calculation of reachability of the graph. The model has been implemented with the proof assistant PVS 6.0 (Prototype Verification System). It makes it possible to prove algorithms of reachability reduction such as Sparsest\_cut.

User identity linkage across social platforms is an important problem of great research challenge and practical value. In real applications, the task often assumes an extra degree of difficulty by requiring linkage across multiple platforms. While pair-wise user linkage between two platforms, which has been the focus of most existing solutions, provides reasonably convincing linkage, the result depends by nature on the order of platform pairs in execution with no theoretical guarantee on its stability. In this paper, we explore a new concept of ``Latent User Space'' to more naturally model the relationship between the underlying real users and their observed projections onto the varied social platforms, such that the more similar the real users, the closer their profiles in the latent user space. We propose two effective algorithms, a batch model(ULink) and an online model(ULink-On), based on latent user space modelling. Two simple yet effective optimization methods are used for optimizing objective function: the first one based on the constrained concave-convex procedure(CCCP) and the second on accelerated proximal gradient. To our best knowledge, this is the first work to propose a unified framework to address the following two important aspects of the multi-platform user identity linkage problem –- (I) the platform multiplicity and (II) online data generation. We present experimental evaluations on real-world data sets for not only traditional pairwise-platform linkage but also multi-platform linkage. The results demonstrate the superiority of our proposed method over the state-of-the-art ones.

The purpose of this research is to propose architecture-driven, penetration testing equipped with a software reverse and forward engineering process. Although the importance of architectural risk analysis has been emphasized in software security, no methodology is shown to answer how to discover the architecture and abuse cases of a given insecure legacy system and how to modernize it to a secure target system. For this purpose, we propose an architecture-driven penetration testing methodology: 4+1 architectural views of the given insecure legacy system, documented to discover program paths for vulnerabilities through a reverse engineering process. Then, vulnerabilities are identified by using the discovered architecture abuse cases and countermeasures are proposed on identified vulnerabilities. As a case study, a telecommunication company's Identity Access Management (IAM) system is used for discovering its software architecture, identifying the vulnerabilities of its architecture, and providing possible countermeasures. Our empirical results show that functional suggestions would be relatively easier to follow up and less time-consuming work to fix; however, architectural suggestions would be more complicated to follow up, even though it would guarantee better security and take full advantage of OAuth 2.0 supporting communities.

In this paper we describe a privacy-preserving method for commissioning an IoT device into a cloud ecosystem. The commissioning consists of the device proving its manufacturing provenance in an anonymous fashion without reliance on a trusted third party, and for the device to be anonymously registered through the use of a blockchain system. We introduce the ChainAnchor architecture that provides device commissioning in a privacy-preserving fashion. The goal of ChainAnchor is (i) to support anonymous device commissioning, (ii) to support device-owners being remunerated for selling their device sensor-data to service providers, and (iii) to incentivize device-owners and service providers to share sensor-data in a privacy-preserving manner.

Digital artifacts on social media can challenge individuals during identity transitions, particularly those who prefer to delete, separate from, or hide data that are representative of a past identity. This work investigates concerns and practices reported by transgender people who transitioned while active on Facebook. We analyze open-ended survey responses from 283 participants, highlighting types of data considered problematic when separating oneself from a past identity, and challenges and strategies people engage in when managing personal data in a networked environment. We find that people shape their digital footprints in two ways: by editing the self-presentational data that is representative of a prior identity, and by managing the configuration of people who have access to that self-presentation. We outline the challenging interplay between shifting identities, social networks, and the data that suture them together. We apply these results to a discussion of the complexities of managing and forgetting the digital past.