Privacy-enhancing Technologies Research Articles

Predicting Online Target Hardening Behaviors: An Extension of Routine Activity Theory for Privacy-Enhancing Technologies and Techniques

ABSTRACT Using representative survey data from Canada, the United States, Australia, the United Kingdom, and five European Union member countries (n= 9,011), this paper predicts the use of privacy-enhancing technologies and techniques as a form of individual target hardening behavior. It presents a novel extension of routine activity theory by revisiting the theory from the perspective of Internet users in their efforts to minimize their likelihood of victimization. The results show that perceived concern and exposure to certain motivated offenders leads to target hardening behaviors, such as using two-factor authentication and antivirus software. Encryption communication services, however, were not associated with concern for any combination of motivated offenders. Moreover, perceived deficiencies in governmental but not company guardianship predicted new protective behaviors.

Explaining the Technology Use Behavior of Privacy-Enhancing Technologies: The Case of Tor and JonDonym

Abstract Today’s environment of data-driven business models relies heavily on collecting as much personal data as possible. Besides being protected by governmental regulation, internet users can also try to protect their privacy on an individual basis. One of the most famous ways to accomplish this, is to use privacy-enhancing technologies (PETs). However, the number of users is particularly important for the anonymity set of the service. The more users use the service, the more difficult it will be to trace an individual user. There is a lot of research determining the technical properties of PETs like Tor or JonDonym, but the use behavior of the users is rarely considered, although it is a decisive factor for the acceptance of a PET. Therefore, it is an important driver for increasing the user base. We undertake a first step towards understanding the use behavior of PETs employing a mixed-method approach. We conducted an online survey with 265 users of the anonymity services Tor and JonDonym (124 users of Tor and 141 users of JonDonym). We use the technology acceptance model as a theoretical starting point and extend it with the constructs perceived anonymity and trust in the service in order to take account for the specific nature of PETs. Our model explains almost half of the variance of the behavioral intention to use the two PETs. The results indicate that both newly added variables are highly relevant factors in the path model. We augment these insights with a qualitative analysis of answers to open questions about the users’ concerns, the circumstances under which they would pay money and choose a paid premium tariff (only for JonDonym), features they would like to have and why they would or would not recommend Tor/JonDonym. Thereby, we provide additional insights about the users’ attitudes and perceptions of the services and propose new use factors not covered by our model for future research.

The OLYMPUS Architecture-Oblivious Identity Management for Private User-Friendly Services.

Privacy enhancing technologies (PETs) allow to achieve user’s transactions unlinkability across different online Service Providers. However, current PETs fail to guarantee unlinkability against the Identity Provider (IdP), which becomes a single point of failure in terms of privacy and security, and therefore, might impersonate its users. To address this issue, OLYMPUS EU project establishes an interoperable framework of technologies for a distributed privacy-preserving identity management based on cryptographic techniques that can be applied both to online and offline scenarios. Namely, distributed cryptographic techniques based on threshold cryptography are used to split up the role of the Identity Provider (IdP) into several authorities so that a single entity is not able to impersonate or track its users. The architecture leverages PET technologies, such as distributed threshold-based signatures and privacy attribute-based credentials (p-ABC), so that the signed tokens and the ABC credentials are managed in a distributed way by several IdPs. This paper describes the Olympus architecture, including its associated requirements, the main building blocks and processes, as well as the associated use cases. In addition, the paper shows how the Olympus oblivious architecture can be used to achieve privacy-preserving M2M offline transactions between IoT devices.

How Privacy Concerns, Trust and Risk Beliefs, and Privacy Literacy Influence Users' Intentions to Use Privacy-Enhancing Technologies

Due to an increasing collection of personal data by internet companies and several data breaches, research related to privacy gained importance in the last years in the information systems domain. Privacy concerns can strongly influence users' decision to use a service. The Internet Users Information Privacy Concerns (IUIPC) construct is one operationalization to measure the impact of privacy concerns on the use of technologies. However, when applied to a privacy enhancing technology (PET) such as an anonymization service, the original rationales do not hold anymore. In particular, an inverted impact of trusting and risk beliefs on behavioral intentions can be expected. We show that the IUIPC model needs to be adapted for the case of PETs. In addition, we extend the original causal model by including trusting beliefs in the anonymization service itself as well as a measure for privacy literacy. A survey among 124 users of the anonymization service Tor shows that trust in Tor has a statistically significant effect on the actual use behavior of the PET. In addition, the results indicate that privacy literacy has a negative impact on trusting beliefs in general and a positive effect on trust in Tor.

The role of technology in governance: The example of Privacy Enhancing Technologies

AbstractThe collection of data, its analysis, and the publication of insights from data promise a range of benefits, but can carry risks for individuals and organizations. This paper sets out considerations regarding the potential role for technologies in governance of data use, and some key limitations. The paper examines the potential of Privacy Enhancing Technologies (PETs) to support organizations and institutions that handle data in governing data use, and considers their role based on their current state of development and the trajectory of technological development. This involves consideration both of how these technologies can potentially enable governments and others to unlock the value of data, and also recognition of both contingent and in principle limitations on the role of PETs in ensuring well-governed use of data.

Emotional and Practical Considerations Towards the Adoption and Abandonment of VPNs as a Privacy-Enhancing Technology

Abstract Virtual Private Networks (VPNs) can help people protect their privacy. Despite this, VPNs are not widely used among the public. In this survey study about the adoption and usage of VPNs, we investigate people’s motivation to use VPNs and the barriers they encounter in adopting them. Using data from 90 technologically savvy participants, we find that while nearly all (98%; 88) of the participants have knowledge about what VPNs are, less than half (42%; 37) have ever used VPNs primarily as a privacy-enhancing technology. Of these, 18% (7) abandoned using VPNs while 81% (30) continue to use them to protect their privacy online. In a qualitative analysis of survey responses, we find that people who adopt and continue to use VPNs for privacy purposes are primarily motivated by emotional considerations, including the strong desire to protect their privacy online, wide fear of surveillance and data tracking not only from Internet service providers (ISPs) but also governments and Internet corporations such as Facebook and Google. In contrast, people who are mainly motivated by practical considerations are more likely to abandon VPNs, especially once their practical need no longer exists. These people cite their access to alternative technologies and the effort required to use a VPN as reasons for abandonment. We discuss implications of these findings and provide suggestions on how to maximize adoption of privacy-enhancing technologies such as VPNs, focusing on how to align them with people’s interests and privacy risk evaluation.

The secret life of PETs

PurposeThe purpose of this paper is to explore to what extent the legal environment influences a user’s choice to employ privacy-enhancing technologies (PETs). Drawing upon existing theoretical frames specific to arbitrariness and uncertainty, this research examines whether interest in PETs is influenced by the legal environment of a country.Design/methodology/approachUsing data from Google Trends, the International Property Rights Index, Freedom House and the Organization for Economic Cooperation and Development, the research analyzes interest in Tor, VPN technology and pretty good privacy (PGP) in 153 countries between 2012 and 2016.FindingsFindings suggest both countries with both higher and lower arbitrariness and uncertainty of law are associated with an increased interest in Tor and PGP. However, interest in VPN technology does not appear influenced by the legal environment and, instead, is influenced by freedom within the press.Research limitations/implicationsThe dual use nature of Tor and PGP is influenced by law enforcement and judiciary effectiveness and transparency and arbitrariness contributing to the public’s interest in decentralized technological protections.Practical implicationsLaw enforcement should continue to police via the technologies rather than shutting them down to protect the identities of those needing to use these technologies for legitimate purposes. Only by embracing the technologies, as opposed to seeing them as hurdles to be banned, may law enforcement agencies remain vigilant to the threats posted by nefarious actors.Originality/valueIn this study, the authors introduce a more robust measure of interest in PETs, and do so with a larger, more substantive sample. By situating this interest within the context of policing, the authors can document the dual use nature of the technology, which can be useful in guiding future research, specifically in the area of policy development and officer training.

The trouble with Article 25 (and how to fix it): the future of data protection by design and default

In its simplest formulation, data protection by design and default uses technical and organizational measures to achieve data protection goals. Although privacy regulators have endorsed privacy-enhancing technologies or PETs for well over thirty years, Article 25 of the General Data Protection Regulation (GDPR) breaks new ground by transforming this idea into a binding legal obligation. But Article 25 as presently conceived is poorly aligned with privacy engineering methods and related privacy-enhancing technologies (PETs). This is especially true of “hard” PETs that place limited trust in third parties (including data controllers) and instead rely on cryptographic techniques to achieve data minimisation. In order to advance data protection in its own right rather than merely reinforce the general principles of the GDPR, Article 25 must be interpreted as requiring the implementation of privacy engineering and hard PETs. A bold way to achieve this is by mandating that data controllers use available hard PETs for data minimisation. More gradual steps include data protection regulators insisting on a central role for privacy engineering and PETs in public sector projects; issuing guidance on Article 25 in very forceful terms that clearly require the implementation of “state of the art” privacy technology; and using their enforcement powers to reward good examples of privacy engineering rather than to penalize failures. NB: This is a pre-copyedited, preprint version of an article accepted for publication in International Data Privacy Law following peer review. The final and updated version was published in International Data Privacy Law, Volume 10, Issue 1, February 2020, Pages 37–56, https://doi.org/10.1093/idpl/ipz019.

Have Your Privacy Cake and Eat It Too: How New Technologies Look to Protect Consumer Privacy While Promoting Innovation

With the rapid proliferation of personal data online, we are seeing an increase in potential dangers, leading some advocates to call for broad limits on personal data generation, collection, and use, emphasizing consumer privacy over beneficial use. Other advocates have expressed concern that broad limits on personal data will stifle innovation. Significantly, a range of privacy enhancing technologies (PETs) have developed which promise to protect consumer privacy while also allowing for the development of personal data-driven products and services that are desired by consumers. While PETs have been discussed in academia and in policy circles as a potential technical solution, this paper describes the actual technologies and implementations that are available or soon to be available. We analyze the potential of current and emerging PETs, with a specific focus on the recent emergence of blockchain-based identity management, to address the fundamental challenges posed by the rapid increase in the generation, collection, and use of personal data. We conclude that these technologies may offer the potential to protect consumer privacy while still supporting innovative products and services enabled by personal data.

GenoPri'17: International Workshop on Genome Privacy and Security

The four papers in this special section were presented at the 4th International Workshop on Genome Privacy and Security (GenoPri) in 2017. This workshop aimed to bring together a highly interdisciplinary community involved in all aspects of genome privacy and security research. This workshop built on its three predecessors, GenoPri’14, GenoPri’15, and GenoPri’16 which were collocated with the Privacy Enhancing Technologies Symposium (PETS), IEEE Symposium on Security and Privacy, and American Medical Informatics Association Annual Fall Symposium (AMIA), respectively. Over the past several decades, genome sequencing technologies have evolved from slow and expensive systems that were limited in access to a select few scientists and forensics investigators to high-throughput, relatively low-cost tools that are available to consumers.

$\mathsf{PrivateLink}$ : Privacy-Preserving Integration and Sharing of Datasets

In privacy-enhancing technology, it has been inevitably challenging to strike a reasonable balance between privacy, efficiency, and usability (utility). To this, we propose a highly practical solution for the privacy-preserving integration and sharing of datasets among a group of participants. At the heart of our solution is a new interactive protocol, PrivateLink. Through PrivateLink, each participant is able to randomize his/her dataset via an independent and untrusted third party, such that the resulting dataset can be merged with other randomized datasets contributed by other participants in a privacy-preserving manner. Our approach does not require key sharing among participants in order to integrate different datasets. This, in turn, leads to a user-friendly and scalable solution. Moreover, the correctness of a randomized dataset returned by the third party can be securely verified by the participant. We further demonstrate PrivateLink's general utilities: using it to construct a structure-preserving data integration protocol. This is particularly useful for private, fine-grained integration of network traffic data. We state the security of our protocols under the well-established real-ideal simulation paradigm and demonstrate practicality by a prototype implementation on: 1) healthcare datasets and 2) DNS and NetFlow datasets.

Encryption for the masses? An analysis of PGP key usage

<p>Despite the rise of alternatives, email remains integral to technology-mediated communication. To protect email privacy the encryption software Pretty Good Privacy (PGP) has been considered the first choice for individuals since 1991. However, there is little scholarly insight into the characteristics and motivations for the people using PGP. We seek to shed light on social aspects of PGP: who is using PGP for encrypted email communication, how and why? By understanding those using the technology, questions on the motivations, usability, and the political dimension of communication encryption can be contextualized and cautiously generalized to provide input for the design of privacy-enhancing technologies. We have greatly extended the scale and scope of existing research by conducting a PGP key analysis on 4.27 million PGP public keys complemented by a survey filled out by former and current PGP users (N = 3,727). We show that a relatively small homogeneous population of mainly western, technically skilled, and moderately politically active males is using PGP for privacy self-management. Additionally, findings from existing research identifying poor usability and a lack of understanding of the underlying mechanisms of PGP can be confirmed.</p>

Privacy Enhancing Technologies in the Internet of Things: Perspectives and Challenges

Internet of Things (IoT) devices have brought much efficiency and convenience to our daily life. However, the devices may collect a myriad of data from people without their consent. Controlling the large amount of data generated from the devices from being misused is critical to mitigate privacy risks. Therefore, privacy protection on personal data has become an important factor in the development of the IoT. Historically, privacy enhancing technologies (PETs) can effectively enhance the privacy and protect users' personally identifiable information. To date, many researchers have stressed the importance of PETs and proposed solutions relevant to different application fields of the IoT. However, to the best of our knowledge, none of the research has analyzed the PETs in IoT from the aspects of privacy threat issues and privacy legislation. As a result, this paper surveys on the solutions of PETs in the field of IoT, which has filtered down from the large number of published academic papers to the 120 primary studies published between 2014 and 2017. After collecting the papers, we categorized them based on the functions and the coverage of privacy protection, and analyzed them from different aspects, ranging from high-level principles of general data protection regulations and ISO/IEC 29100:2011 requirements to the actual resolution of privacy threats in IoT. Thus, we aim to identify the current state of development of the PETs in various fields and examine whether the existing PETs comply with the latest legal principles and privacy standards and reduce the threats to privacy. Finally, recommendations for future research are given based on the results.

The pre-modern self in post-modern times: The rhetoric of privacy in the work of Walter J. Ong, S.J.1

The Edward Snowden revelations of leaked National Security Agency documents in 2013 received considerable attention in the scholarly and popular media. More recently, Facebook and other social media sites have come under scrutiny for their role in the 2016 US elections. Surveys of attitudes consistently indicate that Americans fear identity theft and other problems arising from Internet use. Yet Americans consistently turn over their personal data to Google, Facebook and other large companies. An important 2015 study of Internet browsing habits showed that users, after an initial concern with privacy-enhancing technologies following the Snowden revelations, quickly returned to sports and celebrity gossip as loci of interest. This article teases out reasons for the apparent contradiction. It uses Walter J. Ong’s work, Norbert Elias’s study of manners, along with more recent scholarship on privacy, on the early book trade and on aspects of the early modern period to argue that the contemporary concept of privacy is historically contingent. Historical circumstances and the development of certain technologies encouraged the development of privacy and the self. Current circumstances and technologies are contributing to their decay. This article grows out of two preliminary addresses, one given at the 2016 meeting of the Media Ecology Association in Bologna and the other at a meeting of the Gonzaga University Socratic Club in 2018.

On the Strength of Privacy Metrics for Vehicular Communication

Vehicular communication plays a key role in near-future automotive transport, promising features such as increased traffic safety and wireless software updates. However, vehicular communication can expose drivers' locations and thus poses privacy risks. Many schemes have been proposed to protect privacy in vehicular communication, and their effectiveness is usually evaluated with privacy metrics. However, to the best of our knowledge, (1) different privacy metrics have never been compared to each other, and (2) it is unknown how strong the metrics are. In this paper, we evaluate and compare the strength of 41 privacy metrics in terms of four novel criteria: Privacy metrics should be monotonic, i.e., indicate decreasing privacy for increasing adversary strength; their values should be spread evenly over a large value range to support within-scenario comparability; and they should share a large portion of their value range between traffic conditions to support between-scenario comparability. We evaluate all four criteria on real and synthetic traffic with state-of-the-art adversary models and create a ranking of privacy metrics. Our results indicate that no single metric dominates across all criteria and traffic conditions. We therefore recommend to use metrics suites, i.e., combinations of privacy metrics, when evaluating new privacy-enhancing technologies.

Privacy-enhanced BPMN: enabling data privacy analysis in business processes models

Privacy-enhancing technologies play an important role in preventing the disclosure of private data as information is transmitted and processed. Although business process model and notation (BPMN) is well suited for expressing stakeholder collaboration and business processes support by technical solutions, little is done to depict and analyze the flow of private information and its technical safeguards as it is disclosed to process participants. This gap motivates the development of privacy-enhanced BPMN (PE-BPMN)—a BPMN language for capturing PET-related activities in order to study the flow of private information and ease the communication of privacy concerns and requirements among stakeholders. We demonstrate its feasibility in a mobile app scenario and present techniques to analyze information disclosures identified by models enriched with PE-BPMN.

Privacy Enhancing Technologies implementation: An investigation of its impact on work processes and employee perception

With increasing consumer awareness towards information privacy and government-enforced regulations on data protection, organizations are implementing Privacy Enhancing Technologies (PETs) to provide systematic protection on consumers’ personal data. Current PETs literature focused mostly on the design and implementation of the technology without touching on its impact. Implementation literature has also examined the effects of various technologies on changes in work processes and employee perception but has yet to explore that of PETs. Therefore, the objective of this study is to understand the effects of PETs implementation on employees’ work processes as well as their perception towards the implementation. In-depth interview data was collected from three groups of affected employees belonging to one large mobile telecommunications company. Results show that PETs affected workload, communication level and data access, which led to different levels of changes depending on the nature of the work. The employees perceived PETs as useful. However, they perceived the company as not being properly prepared for the implementation, and also raised concerns on vendor accountability and the sustainability of the PETs. Our findings have implications for organizations planning to implement PETs.

The Integrated Holistic Security and Privacy Framework Deployed in CrowdHEALTH Project.

Introduction:Individuals and healthcare providers need to trust that the EHRs are protected and that the confidentiality of their personal information is not at stake.Aim:Within CrowdHEALTH project, a security and privacy framework that ensures confidentiality, integrity, and availability of the data was developed.Methods:The CrowdHEALTH Security and Privacy framework includes Privacy Enhancing Technologies (PETs) in order to comply with the GDPR EU laws of data protection. CrowdHEALTH deploys OpenID Connect, an authentication protocol to provide flexibility, scalability, and lightweight user authentication as well as the attribute-base access control (ABAC) mechanism which supports creating efficient access control policies.Results:CrowdHEALTH integrates ABAC with OpenID Connect to build an effective and scalable base for end-users’ authorization. CrowdHEALTH’s security and privacy framework interacts with other CrowdHEALTH’s components, for instance the Big Data Platform, that depends on user authentication and authorization. CrowdHEALTH users are able to access the CrowdHEALTH’s database based on the result of an ABAC request. Moreover, due to the fact that the CrowdHEALTH system requires proofs during the interactions with data producers of low trust or low reputation level, the requirements for the Trust and Reputation Model have been identified.Conclusion:The CrowdHEALTH Integrated Holistic Security and Privacy framework meets the security criteria for an e-health cross-border system, due to the adoption of security mechanisms, such as user authentication, user authorization, access control, data anonymization, trust management and reputation modelling. The implemented framework remains to be tested to ensure its robustness and to evaluate its performance. The holistic security and privacy framework might be adapted during the project’s life circle according to new legislations.

Who Is Responsible for Data Processing in Smart Homes? Reconsidering Joint Controllership and the Household Exemption

The growing industrial and research interest in protecting privacy and fighting cyberattacks for smart homes has sparked various innovations in security- and privacy-enhancing technologies (S/PETs) powered by edge computing. The complex technical set-up has however raised a whole series of legal issues surrounding the regulation of smart home with data protection law. To determine how responsibility and accountability should be fairly assumed by stakeholders, there is a pressing need to first clarify the roles of these parties within the existing data protection data protection legal framework. This article focuses on two legal concepts under the GDPR as the mechanisms to (dis)assign responsibilities to various categories of entities in a domestic IoT context: joint controllership and the household exemption. A close examination of the relevant provisions and case-law shows a widening notion of joint controllership and a narrowing scope for the household exemption. While this interpretative approach may prevent evasion of accountability in specific cases, it may lead to the unintended consequence of imposing disproportionate compliance burdens on developers, contributors, and users of smart home safety technologies. By discouraging users to adopt S/PETs, data protection law may likely lead to a lower level of privacy and security protection. The differential responsibilities among joint controllers as envisaged in case-law may reconcile the tensions to some degree, but certain limitations remain. The regulatory dilemma in this regard highlights some underlying assumptions of data protection law that are no longer valid with regard to a smart home, and thus calls for further conceptual and empirical studies on fair reassignment of responsibility and accountability in a domestic IoT setting.

Systematizing Genome Privacy Research: A Privacy-Enhancing Technologies Perspective

Abstract Rapid advances in human genomics are enabling researchers to gain a better understanding of the role of the genome in our health and well-being, stimulating hope for more effective and cost efficient healthcare. However, this also prompts a number of security and privacy concerns stemming from the distinctive characteristics of genomic data. To address them, a new research community has emerged and produced a large number of publications and initiatives. In this paper, we rely on a structured methodology to contextualize and provide a critical analysis of the current knowledge on privacy-enhancing technologies used for testing, storing, and sharing genomic data, using a representative sample of the work published in the past decade. We identify and discuss limitations, technical challenges, and issues faced by the community, focusing in particular on those that are inherently tied to the nature of the problem and are harder for the community alone to address. Finally, we report on the importance and difficulty of the identified challenges based on an online survey of genome data privacy experts.