Depending on the Kindness of Strangers? Trust Relationships in Ambient Societies

The vision of the ambient society relies on the constant exchange of personal information among multiple devices, individuals and organisations. The high number of microtrust decisions required in such a scenario calls for automated trust management. In this paper we discuss a set of contextual properties of transactions that ensure trust and trustworthy action in everyday situation and suggest how they can be incorporated in trust management for ambient technologies. We identify institutions, repeated interactions and reputation as contextual properties that support cooperation. We then discuss the limitations and risks of assuring cooperation based on contextual properties alone. Firstly, a subjective assessment of personal properties (e.g. benevolence and integrity) also forms an important basis for trust in others. Furthermore trust based on contextual properties is hard to establish in the case of vague outcomes, and multi-dimensional risks. Finally, establishing one’s own trustworthiness requires giving access to personal information. Ambient technologies must also allow individuals to remain untrusted but private.