Novel scalable aggregation algorithm of feedback trust information

Focusing on the problem that current dynamic trust aggregation algorithms searching for feedback trust information is based on trust chain in broadcast way, leading to slow in convergence and bad in scalability, a new scalable feedback trust information aggregation algorithm is proposed, in which the concept and definition of direct trust tree (DTT) are presented. Based on DTT a novel aggregating algorithm of scalable feedback trust information is proposed, and the DTT is constructed according to node's direct trust relation. Then, the feedback trust information is searched by using DTT instead of in broadcast manner. Two new parameters, quality factor and distance factor, are introduced to adjust the scale of aggregating computation automatically. Simulation results show that the algorithm remarkably enhances the convergence of feedback trust information aggregating computation. Moreover, it has better detecting capability against malicious feedback actions and has stronger robustness when the ratio of malicious nodes is increased.