A lightweight permission-based blockchain for IoT environments

The Internet of Things (IoT) is a rapidly evolving field. As it continues to create new applications in life, industry, agriculture and infrastructure, new challenges surface with them. The application of IoT networks range from medical devices
to industrial robots. Such application dynamics present several new networking challenges. IoT networks are inherently heterogamous in terms of device capabilities, data volume, velocity and variety. This paper explores the possibility and effectiveness of combining IoT with the original concepts of blockchain
technology in maintaining a verifiable ledger of polymorphic transactions to enable secure communication between devices. We present a practical implementation of a flexible blockchain system as a lightweight attachment to IoT devices. This system embeds a policy manager which defines and regulates the permissions required for authorised transactions; only a single device is permitted to amend this policy. We then demonstrate this system inside a reference topology by simulating activity between multiple homogeneous IoT devices communicating over the blockchain. We include devices of varying capabilities to demonstrate how those with more resources can support the
chain whilst weaker devices consume from it.