ABSTRACT
Industrial Internet of Things (IoT) depends on a vast array of sensors, processing elements, and actuators to automate data collection, processing, and response. One of the major challenges in the stage of data collection is the accuracy of electromechanical sensors. The concept of Proof-of-Stake (PoS), which is popular in Ethereum blockchain platform, can be used to improve the robustness of data collection. PoS works by selecting a subset of nodes based on their holdings called “stakes”, to perform a specific task. This algorithm is incorporated into IIoT by assigning a stake value to each node internally. The stake is assigned a predefined value during installation and changes periodically based on accuracy. A stake threshold is set so that only those nodes with stake above that value are considered contributors and others act as validators. During the initial setup, everyone validates every other node. Beyond that, the selection of contributors is repeated periodically. At every time interval, validators take the global average of contributors and find the deviation from the observed value. This is compared with a deviation limit. If none are within the limit, it indicates outliers, and the system invalidates itself. Otherwise, the node with the least deviation will emerge victoriously and send its value across to the processing unit. Those nodes with high deviation will have a part of their stake transferred to those with less deviation. Hence, the total stake remains the same, whereas the distribution keeps changing. The advantage is that this process is entirely distributed once all nodes multicast their readings to the validator group. This also ensures that sensors with persistent errors are singled out because they cannot recover their stake.
