The emergence of ubiquitous computing as a new design paradigm poses significant challenges for HCI and interaction design. Traditionally, human-computer interaction has taken place within a constrained and well-understood domain of experience – single users sitting at desks and interacting with conventionally-designed computers employing screens, keyboards and mice for interaction. New opportunities have engendered considerable interest in “context-aware computing” – computational systems that can sense and respond to aspects of the settings in which they are used. However, considerable confusion surrounds the notion of “context” – what it means, what it includes, and what role it plays in interactive systems. This paper suggests that the representational stance implied by conventional interpretations of “context” misinterprets the role of context in everyday human activity, and proposes an alternative model that suggests different directions for design.

Ubiquitous and mobile technologies create new challenges for system security. Effective security solutions depend not only on the mathematical and technical properties of those solutions, but also on people’s ability to understand them and use them as part of their work. As a step towards solving this problem, we have been examining how people experience security as a facet of their daily life, and how they routinely answer the question, “is this system secure enough for what I want to do?” We present a number of findings concerning the scope of security, attitudes towards security, and the social and organizational contexts within which security concerns arise, and point towards emerging technical solutions.

The critical role of the human operator in security operations has not been a focus of existing tools created by security developers. In this paper we describe interface requirements for usable and effective security operations tools to assess security situational awareness on large and complex computer networks. We have developed two prototype security monitoring tools based on these interface requirements and are progressing on usability studies to evaluate their effectiveness.

In our research, we have been concerned with the question of how to make relevant features of security situations visible to users in order to allow them to make informed decisions regarding potential privacy and security problems, as well as regarding potential implications of their actions. To this end, we have designed technical infrastructures that make visible the configurations, activities, and implications of available security mechanisms. This thus allows users to make informed choices and take coordinated and appropriate actions when necessary. This work differs from the more traditional security usability work in that our focus is not only on the usability of security mechanism (e.g., the ease-of-use of an access control interface), but how security can manifest itself as part of people’s interactions with and through information systems (i.e., how people experience and interpret privacy and security situations, and are enabled or constrained by existing technological mechanisms to act appropriately). In this paper, we report our experiences designing, developing, and testing two technical infrastructures for supporting this approach for usable security.

As interest in usable security spreads, the use of visual approaches in which the functioning of a distributed system is made visually available to end users is an approach that a number of researchers have examined. In this paper, we discuss the use of the social navigation paradigm as a way of organizing visual displays of system action. Drawing on a previous study of security in the KaZaa peer to peer system, we present some examples of the ways in which social navigation can be incorporated in support of usable security.

Security software is often difficult to use thus leading to poor adoption and degraded security. This paper describes a usability study that was conducted on the software ‘Polaris’. This software is an alpha release that uses the Principle of Least Authority (POLA) to deny viruses the authority to edit files. Polaris was designed to align security with usability. The study showed that despite this aim, usability problems remained, especially when the study participants had to make security related decisions. They also showed apathy towards security, and knowingly compromised their security to get work done faster. This study also demonstrates the difficulty in achieving security and usability alignment when the usability is a post hoc consideration added to a developed product, rather than being integrated from the start. The alleviation of usability problems from security software proposed in this paper are threefold: reducing the burden on the user to make security related decisions, counteracting user’s apathy by ensuring that the fast way of doing things is the secure way, and integrating security software with the operating system throughout development.

Usability is the weakest link in the security chain of many prominent applications. A set of security usability principles should therefore be considered when designing and engineering IT security solutions. When improving the usability of existing security applications, it is necessary to examine the underlying security technologies used to build them, and consider whether they need to be replaced by totally new security technologies that provide a better basis for good usability. This paper examines a set of security usability principles, proposes how they can be incorporated into the risk management process, and discusses the benefits of applying these principles and process to existing and future security solutions. 1.

Although security is normally thought of as a technical problem, we believe that it is more appropriately formulated as a practical problem that users routinely enounter and solve. Essentially, their problem is to determine the match between a system’s configuration and their needs. However, the resources to make informed decisions are rarely available. As a first step towards solving this problem, we present some preliminary findings from a study currently under way, which seeks to investigate the mental models and conceptual arrangements by which people understand the problems of everyday security.

“People are the weakest link in the security chain ” – Bruce Schneier The aim of the thesis is to investigate the process of designing secure systems, and how designers can ensure that security mechanisms are usable and effective in practice. The research perspective is one of security as a socio-technical system. A review of the literature of security design and Human Computer Interactions in Security (HCISec) reveals that most security design methods adopt either an organisational approach, or a technical focus. And whilst HCISec has identified the need to improve usability in computer security, most of the current research in this area is addressing the issue by improving user interfaces to security tools. Whilst this should help to reduce users ’ errors and workload, this approach does not address problems which arise from the difficulty of reconciling technical requirements and human factors. To date, little research has been applied to socio-technical approaches to secure system design methods. Both identifying successful socio-technical design approaches and gaining a better understanding of the issues surrounding their application is required to address this

In order to be effective, secure systems need to be both correct (i.e. effective when used as intended) and dependable (i.e. actually being used as intended). Given that most secure systems involve people, a strategy for achieving dependable security must address both people and technology. Current research in Human-Computer Interactions in Security (HCISec) aims to increase dependability of the human element by reducing mistakes (e.g. through better user interfaces to security tools). We argue that a successful strategy also needs to consider the impact of social interaction on security, and in this respect trust is a central concept. We compare the understanding of trust in secure systems with the more differentiated models of trust in social science research. The security definition of “trust ” turns out to map onto strategies that would be correctly described as “assurance ” in the more differentiated model. We argue that distinguishing between trust and assurance yields a wider range of strategies for ensuring dependability of the human element in a secure socio-technical system. Furthermore, correctly placed trust can also benefit an organisation’s culture and performance. We conclude by presenting design principles to help security designers decide “when to trust ” and “when to assure”, and give examples of how both strategies would be implemented in practice. 1.