An integrated trust and reputation model for open multi-agent systems

Abstract

Trust and reputation are central to effective interactions in open multi-agent systems (MAS) in which agents, that are owned by a variety of stakeholders, continuously enter and leave the system. This openness means existing trust and reputation models cannot readily be used since their performance suffers when there are various (unforseen) changes in the environment. To this end, this paper presents FIRE, a trust and reputation model that integrates a number of information sources to produce a comprehensive assessment of an agent's likely performance in open systems. Specifically, FIRE incorporates interaction trust, role-based trust, witness reputation, and certified reputation to provide trust metrics in most circumstances. FIRE is empirically evaluated and is shown to help agents gain better utility (by effectively selecting appropriate interaction partners) than our benchmarks in a variety of agent populations. It is also shown that FIRE is able to effectively respond to changes that occur in an agent's environment.

CRM: An efficient trust and reputation model for agent computing

“…We also compare our model with five well known models as benchmarks: FIRE [10,11], Referral [33,34], SPORAS [35], Travos [27] and BRS [12]. All these models are explained in details and discussed in the related work section (Section 6).…”

“…However, in biased environments, agents can reveal inaccurate information. Comparison is done first between CRM, FIRE [10] (a successful trust model with high performance), SPORAS [35] (a centralized approach), and Referral [33] (following the concept of reference in an honest environment). Travos [27] and BRS [12] are the two other models that we compared CRM with in terms of how they survive in biased environment where agents constantly change their behaviors.…”

“…This may impact the selection of good providers from the beginning of simulation. FIRE agents [10] regulate the problem of collecting the required information by the evaluator to assess the trust of his partner. In addition, they apply certified reputation introduced by the trustee agent.…”

“…Attempting to maintain a trust-based approach, different frameworks have been proposed to represent and assess the trust agents have in one another. The most recent research proposals in trust models for multi-agent systems are as follows: (a) interaction trust, based on the direct interactions of two parties [30,31]; (b) trust based on the type of prior interactions [10,11,22]; (c) witness reputation based on certified (and possibly encrypted) references obtained by the agent to be evaluated after interacting with other agents. These references are then made public to any other agent who wants to interact with this agent [10,12,17,21,27]; and (d) referenced reputation, based on references from other agents detailing a particular agent's behavior [5,6,10,11].…”

“…Since agents might be selfish, receiving fake information by particular agent(s) is always possible. This problem does exist even when a certified reputation [10] is provided by the agent to be evaluated. In this case, the final trust rate would be affected by non-reliable information and eventually the agents' perception of their surrounding environment will not be accurate.…”