AEchain: A lightweight blockchain for IoT applications

Abstract

IoT nodes comprise of sensors and resource-constrained embedded systems. On the other hand, blockchain is regarded as computationally expensive due to the consensus algorithm (e.g. Proof of Work) and hash computation (i.e. Merkle tree). Therefore, it is challenging to apply blockchain to an IoT system. This work presents a unique concept that integrates blockchain with lightweight cryptographic solutions targeting resource-constrained IoT sensor nodes. In particular, proof of authentication utilizing a lightweight authenticated encryption (AE) scheme to achieve consensus is proposed. Each IoT sensor node generates its own distinctive tag based on the input sensor data, and broadcasts it to the blockchain network. The trusted nodes (e.g. a gateway) in the network authenticate sensor nodes using the lightweight AE scheme. The authenticated block is then hashed by a lightweight hash function and added to the blockchain. The proposed proof of authentication scheme can be implemented in software (e.g. microcontroller) or hardware platform (e.g. FPGA, ASIC). Experimental results show that lightweight authentication can perform 1.34M authentications-per-second with only 6.55k look-up tables (LUTs) on the Spartan- 6 FPGA platform. This high-throughput authentication can speed up the consensus in blockchain, utilizing few resources and making it very suitable for applications in IoT sensor nodes IEEE