PeerReview analysis and re-evaluation for accountability in distributed systems or networks

Accountability implies that any entity should be held responsible for its own specific action or behavior so that the entity is part of a larger chain of accountability. PeerReview [1] is designed as a practical system that provides accountability for distributed systems. A key assumption in PeerReview is that a message sent from one correct node to another will be eventually received. In the real world, however, message loss is commonplace and unavoidable due to the dynamics and uncertainties of the current Internet, and it prevents a message from always reaching its destination. Beginning with this point, we have comprehensively analyzed the behavior of PeerReview with the assumption that, eventually, a message will probably be lost. We have shown that PeerReview would be unable to maintain its completeness and accuracy under such a circumstance. We present six possible errors and the causes from which they originate. We re-evaluated PeerReview with two newly defined metrics, Node Accountability and System Accountability, which are employed to assess the degree of system accountability. Simulation results show that message loss decreases the performance of PeerReview in terms of both metrics.