Messages conveyed to us in everyday life often have an influence on our decisions and behaviors. The more trustworthy a message is considered the higher will be it's impact on the recipient. Trust is a very significant commodity in communication. But how is trust established? A variety of factors influences trust establishment, among them integrity, reputation, credibility, reliability, congruity, predictablity, and responsibility.
We argue that for message-based communication, a more general notion of context information needs to be taken into consideration to determine the trustworthiness of a message. The decision whether or not to trust a piece of data can depend on many factors including creator (who) of the data (what), time (when), location (where), and intent (why) of origination, social context of receiver and many more. Generally, context information can have impact on trust-relevant aspects of communications. Context information can characterize a situation of any entity---be it a person, place, or object---that is relevant to the interaction between a user and an application, including the user and the application themselves.
Another advantage of making context explicit in message exchanges is that this information can be used in trust policies. For example, a policy can state that news information about a particular location is to be trusted if the reporting entity was at the location at the time when the event occurred. In this sense, policies define how to process context information to derive trustworthiness assertions. On the basis of our integrated context and message ontology, we will illustrate sample trust policies and discuss reasoning strategies.
This research is a collaboration between Santtu Toivonen from the Information Technology institute of VTT and Grit Denker from the Computer Science Lab of SRI International.