“…There have been some efforts to produce mathematical definitions of trust [22,10], however intuitive informal definitions, such as "the degree of subjective belief about the behaviors of (information from) a particular entity" [8], or "the expectation that a service will be provided or a commitment will be fulfilled" [15], are convenient for the purposes of this paper. Trust research can be organized [3] in four major areas: (1) policy-based trust, (2) reputation based trust, (3) general models of trust and (4) trust information resources, related with the following applications: networking, semantic web, computational models, game theory and agents, software engineering and information resources.…”