Design of Proof-of-Stake PBFT Algorithm for IoT Environments

Blockchain ledgers are being increasingly used in Internet of Things (IoT) and Internet of Vehicles (IoV) applications. However, Proof of Work consensus is unsuitable in an IoV setting, which is why other paradigms need to be investigated. In this work we integrate Proof of Stake (PoS) consensus technique with multiple entry Practical Byzantine Fault Tolerance voting in a permissioned blockchain network. We introduce several PoS classes based on combination of initial stake and truthfulness of voting. We also describe a differentiated medium access approach similar to Enhanced Distribution Function (EDCA). Using a Semi Markov Process-based model, we derive the probability of reaching consensus and highlight the impact of the populations of individual stake/priority classes on achieving consensus. Our results show the impact of numbers of nodes from classes with different voting behavior on consensus probability. Results also show differentiation through the number of blocks linked per second, success probability in leadership application and delay in leader selection for node belonging to certain class. These values show how much revenue a node from given class can collect from its clients depending on initial stake and voting behavior.