A Self-Scaling Dynamic Blockchain Model for IoT.

Due to its immutability, blockchain is a potential solution for the heterogeneous, non-secure IoT. Nevertheless, scalability, high throughput, consensus efficiency as well as decentralization and node capacity considerations represent challenges that need to be addressed in order to successfully implement blockchain technology in the IoT context. Our proposed multitiered Self-Scalable Dynamic architecture uses a positioning technique to efficiently locate nodes that participate in the consensus. The architecture's forest hierarchy shrinks and expands to maintain a balance between control decentralization and node management overhead. A colocality mechanism further improves consensus efficiency. Consensus time is considerably reduced as consensus is achieved by a small number of nodes, a number logarithmically bounded compared to the number of nodes at the levels beneath. Our model significantly outperforms flat and two-tiered models in simulations, providing a solid proof of concept.