I have recently completed my year in industry placement at nChain, a blockchain research and development company in London. During the placement I was tasked with working on an academic paper titled “A Blockchain-based Control and Communication System for Multilevel IoT Networks”. The paper lays out a Multilevel IoT system that combines a centralised local command-and-control hierarchy with the distributed Bitcoin blockchain acting as back-end infrastructure.

Users can create their own customizable multi-level control hierarchy, and permission or restrict devices as needed using on-chain certificates contained within Bitcoin transactions. Certificates can be verified by other IoT nodes via the blockchain. Certification can be revoked by spending the UTXO (Transaction output) that contains a devices certificate. Commands, status updates and other related actions can be appended to Bitcoin transactions generated by an IoT node’s wallet. Transactions are sent peer-to-peer between the IoT nodes, and then sent to bitcoin miners to be published. This hybrid system removes the single point of failure that comes with third-party data storage while also providing data providence and immutability. I will be presenting the paper at the 2023 IEEE Future Networks World Forum (FNWF) on 13/11/2023.

After drafting, publishing, and presenting the paper, I believe the next logical step is to create a working prototype of the system. I have had discussions with my placement provider, as well as Wendy Ivins, and we are in the process of organising a project in affiliation with nChain.

Firstly, I will setup the hierarchical structure of the network, connecting the master node to a number of servant and slave nodes, as well as end devices. After the initial network setup, I will focus on the user interface for the master node. The functionality of the user interface must handle on-chain certificates, command messaging, and key masking. We can discuss these three areas in more detail if you are interested in supervising my project.

As a security and forensics student, my report will focus on how blockchain integration helps the system to satisfy the CIA security triad and nonrepudiation. The patent-pending key masking technique that I worked on during my placement can be used to mask the public key of every IoT node. This increases privacy, whilst still ensuring data visibility (for nodes with the correct decryption keys), and device visibility for certified nodes on the local IoT network.