The trust and reputation models were introduced to restrain the impacts caused by rational but selfish
peers in P2P streaming systems. However, these models face with two major challenges from dishonest
feedback and strategic altering behaviors. To answer these challenges, we present a global trust model
based on network community, evaluation correlations, and punishment mechanism. We also propose a
two-layered overlay to provide the function of peers’ behaviors collection and malicious detection.
Furthermore, we analysis several security threats in P2P streaming systems, and discuss how to defend
with them by our trust mechanism. The simulation results show that our trust framework can successfully
filter out dishonest feedbacks by using correlation coefficients. It can effectively defend against the
security threats with good load balance as well.