Blockchain Checksum for Establishing Secure Communications for Digital Twin Technology

As Digital Twin technology continues to be developed for the power grid and other high value applications, the security and accuracy of the remote sensor data is of extreme importance. In this paper, we propose a novel implementation of the SHA-256 hash algorithm to create a blockchain of sensor readings. The implementation hashes the current sensor reading to the previous reading(s) from the sensor through a chained checksum SHA-256 algorithm. The enhanced chained-checksum is able to establish the trustworthiness of the communications between the control center and the remote sensor based on the length of the unbroken linked list. The chain of sensor readings act as a sophisticated checksum for the middleware communications used in the digital twin environment which often times are not secure. While the concept is based on blockchain technology, this implementation is specifically designed for two party communications, in this case the outstation and the control center. To accommodate the two party communications, the implementation allowed for the removal of some of the features commonly used in blockchain, such as consensus polling or the proof of work algorithm, and replaced them with historical values to establish the ground truth. To show the advantages of the chained checksum, the SHA-256 algorithm has been implemented in the IEEE 33-bus benchmark system in the Typhoon Hardware in the Loop (HIL) real-time simulator.