Trust Management Methodologies for the Web

Abstract

Trust and its support with appropriate trust management methodologies and technologies is becoming one crucial element for wider acceptance of web services. In the computing society trust and related issues were addressed already in the nineties of the former century, but the approaches from that period were about security, more precisely security services and security mechanisms. These approaches were followed by more advanced ones, where the first branch was based on Bayesian statistics, the second branch was based on Dempster-Shafer theory of evidence and its successors, most notably subjective logic, and the third branch originated from game theory. It is, however, important to note that at the core of trust there are cognition, assessment processes, and they are governed by various factors. Consequently, trust management methodologies should take these factors, which may ne rational, irrational, contextual, etc., into account. This research contribution will therefore provide an extensive overview of existing methodologies in the computer sciences field, followed by their evaluation in terms of their advantages and disadvantages. Further, some latest experimental results will be given that identify and evaluate some of those most important factors mentioned above. Finally, we will present a new trust management methodology called Qualitative Assessment Dynamics, QAD (aka Qualitative Algebra) that complements existing methodologies mentioned above, and that is aligned with the results of the latest experimental findings.