Designing a SHA-256 processor for blockchain-based IoT applications

An increasing number of Internet of Things applications have been recently considering the use of the blockchain technology, calling for dedicated computational capabilities of the underlying devices. This poses an inherent challenge in an application domain notoriously characterised by several, often stringent limitations in terms of available resources. This paper focuses on a key component of the blockchain technology, the SHA-256 hash function, proposing a hardware accelerator which can be adapted to different requirements according to the application context. Experimental results show how the proposed accelerator can be used to satisfy different sets of constraints, effectively providing low-end devices with the computational capabilities required to undertake complex tasks such as blockchain protocols.