A blockchain-based credibility evaluation scheme for navigational event dissemination in the internet of ships

This paper proposes a blockchain-based credibility evaluation for navigational event dissemination, which constitutes a significant functionality for the ship trust management over Internet of Ships (IoS). This enables evaluating and calculating the credibility of the navigational events announced by other ships during their navigation. The presented scheme verifies the credibility of navigational events by introducing cooperative ratings from the involved ships. Bayesian inference models are utilized as the basic estimation about the authenticity of the event, upon which the Hidden Markov Model (HMM) is leveraged to update the reputation of the relevant ships from their current reputation and the ratings they comment about the event. In addition, a Delegated Proof of Stake (DPoS) consensus mechanism based on the reputation of the ship, called R-DPoS, is designed to prioritize ships with higher trustworthiness values to be elected as witness ships, to maintain the stability and efficiency of block generation in the system. In order to validate the feasibility and effectiveness of the proposed scheme, a series of simulation experiments are conducted. The experimental results show that the proposed scheme has an accuracy of more than 80 % for navigational events in most cases, which not only effectively recognize the credibility of navigational events and update the trustworthiness value of the relevant ships, but also suppress the malicious cyber behavior of ships, enhancing the security and stability of the cyberspace of the IoS.