A Novel Approach to Evaluate Trustworthiness and Uncertainty of Trust Relationships in Peer-to-Peer Computing

In peer-to-peer computing, traditional security mechanisms that are based on pre-registration are hardly useful because users are dynamic and can not be pre-defined. Hence trust models were introduced into peer-to-peer systems. In this paper, a novel trust model is proposed, which employs a new approach to model trustworthiness and uncertainty of trust relationships between peers, namely cloud-model. Since the cloud-model is exotic and still in the progress of development, it can not be applied into modeling trust directly, we extend it first according to our need. Then we present an extended-cloud-model-based trust model (ECMBTM). To prove the validity of ECMBTM, a simulation experiment was carried out, and ECMBTM was compared quantificationally with three typical trust models, which are based on different mathematic theories. And the experiment results demonstrate the advantage of ECMBTM preliminarily.