We define and formalise a generic cryptographic construction that underpins coupling of companion devices, e.g., biometrics-enabled devices, with main devices (e.g., PCs), in a user-aware manner, mainly for on-demand authentication and secure storage for applications running on the main device. We define the security requirements of such constructions, provide a full instantiation in a protocol-suite and prove its computational as well as Dolev-Yao security. Finally, we implement our protocol suite and one password-manager use-case.

Encouraging and supporting diversity and inclusion in computer science research communities is a critical issue for many reasons, including the ethical and robust design, delivery and publication of research that addresses real-world situations ranging from the use of digital tools in health to predictive policing to workplace hiring practices, just to name a few. One way to measure diversity is to apply analytical research methods to data sourced from the public domain for use in research. However, attempts to measure diversity using public data may themselves raise legal and ethical questions about the provenance of the data, research methods adopted, and treatment of diversity in the publication of results. This article interrogates the challenges of measuring diversity using public data, examining an illustrative case study framed around an academic research project at an Australian university using a public data set to identify gender representation in computer science communities. Employing a critical data governance perspective, we point to a range of ethical and legal concerns and recommend greater regulatory guardrails to better balance public interests in research and the privacy, data protection and other ethical interests of research subjects.

The Prêt à Voter cryptographic voting system was designed to be flexible and to offer voters a familiar and easy voting experience. In this article, we present our development of the Prêt à Voter design to a practical implementation used in a real state election in November 2014, called vVote. As well as solving practical engineering challenges, we have also had to tailor the system to the idiosyncrasies of elections in the Australian state of Victoria and the requirements of the Victorian Electoral Commission. This article includes general background, user experience, and details of the cryptographic protocols and human processes. We explain the problems, present solutions, then analyze their security properties and explain how they tie in to other design decisions.

The Secure Web Bulletin Board (WBB) is a key component of verifiable election systems. However, there is very little in the literature on their specification, design and implementation, and there are no formally analysed designs. The WBB is used in the context of election verification to publish evidence of voting and tallying that voters and officials can check, and where challenges can be launched in the event of malfeasance. In practice, the election authority has responsibility for implementing the web bulletin board correctly and reliably, and will wish to ensure that it behaves correctly even in the presence of failures and attacks. To ensure robustness, an implementation will typically use a number of peers to be able to provide a correct service even when some peers go down or behave dishonestly. In this paper we propose a new protocol to implement such a Web Bulletin Board, motivated by the needs of the vVote verifiable voting system. Using a distributed algorithm increases the complexity of the protocol and requires careful reasoning in order to establish correctness. Here we use the Event-B modelling and refinement approach to establish correctness of the peered design against an idealised specification of the bulletin board behaviour. In particular we have shown that for n peers, a threshold of t > 2n/3 peers behaving correctly is sufficient to ensure correct behaviour of the bulletin board distributed design. The algorithm also behaves correctly even if honest or dishonest peers temporarily drop out of the protocol and then return. The verification approach also establishes that the protocols used within the bulletin board do not interfere with each other. This is the first time a peered secure web bulletin board suite of protocols has been formally verified.