Security and trust in context-aware applications

Abstract

Context-aware appliances are maturing to enter the market place. The sum of smart phones and tablets sold begins to outnumber the number of desktop PCs sold. The number of sensors built into these systems and the processing power also has increased. However, most importantly, contextaware applications platforms are entering the market, making use of sensory information to provide users with advanced functionality as well as novel means of access to information in their environment. As context-aware systems are leaving the laboratories and enter the life of a growing portion of the population, it becomes increasingly important to ensure that crucial features of security and privacy are added to foster and maintain the trust of users. This transition from applications in the laboratory to marketable apps has been a focus of recent research, at conferences such as the Context conference, whose 2011 edition focused on the challenges of commercializing context. This theme issue came out of the increasing demand for making context-aware applications secure and trustworthy. Conventional techniques cannot fully cover the breadth of new challenges of context-aware applications. Knowledge about the context of users allows an application to support them better, and it also provides valuable information not only to advertising companies but can also—if not adequately protected—be used for malicious purposes: Location information about a user is as valuable to his friends as it is to a burglar. Moreover, information that is made accessible to friends and family members and information to be provided, for instance, to advertisers or employers need to be separated. The articles collected in this theme issue address challenges and solutions on several levels of a context-aware system, its design, and usage. Hoffmann and Sollner discuss how software engineering methods can be adapted using a concept of trust from the behavioral sciences. Acknowledging that it is better to present users with a trustworthy application from the start, they present a strategy for including evaluations of several parameters of trust into a conventional interview-based user study. A major challenge in context-aware systems is their dependence on the physical and social world. Locationaware systems act within the personal spaces of an individual and need to be aware of the non-spatial aspects of a location, so as not to be considered invasive by a user. The article by Toch addresses the acquisition of such hard to formalize knowledge by means of crowd-sourcing: The author reasons that, although powerful privacy controls are required, they are difficult in their use and not always accurate. By collecting and analyzing the opinion of a large number of users, his system can inform the mobile device whether to allow or deny access to location information in a specific context. As mobile devices become personal companions of their owners, containing not only sensitive communication data R. Mayrhofer School of Informatics/Communications/Media, University of Applied Sciences Upper Austria, FH OO, Studienbetriebs GmbH, Softwarepark 11, 4232 Hagenberg, Austria e-mail: rene.mayrhofer@fh-hagenberg.at