Resilient, Auditable and Secure IoT-Enabled Smart Inverter Firmware Amendments With Blockchain

The solar industry in residential areas has been witnessing an astonishing growth worldwide. At the heart of this transformation, affecting the edge of the electricity grid, reside smart inverters (SIs). These IoT-enabled devices aim to introduce a certain degree of intelligence to conventional inverters by integrating various grid support capabilities (e.g., voltage and frequency control). However, with the remarkable automation of these devices come enormous security risks. Thus, rising rates of vulnerabilities have increased the necessity for designing resilient, auditable, and secure SIs' firmware over the air (FOTA) amendment schemes suitable for this heterogeneous SIs-based ecosystem. In this regard, we propose leveraging blockchain as an innovative technology to guarantee these cybersecurity requirements. In this article, we present the design of a distributed FOTA scheme, namely, RASSIFAB, governing the process of amending SIs' firmware within residential areas in an immutable and scalable manner. The scheme was implemented on a blockchain test network to assess its functionalities and performance. We also carried out a security evaluation to determine whether RASSIFAB is resistant to various identified threats. The obtained results confirm that the scheme is efficient and sound. They also indicate that RASSIFAB ensures reliable and authentic firmware amendments even with malicious insiders, differentiating our framework from the existing ones.