An Efficient and Secure DAG-based LoRaWAN System

The conventional LoRa system faces the challenges of security and privacy due to centralized architecture and transparent forwarding mechanism. To address these challenges, a Directed Acyclic Graph (DAG)based LoRaWAN system is proposed in this paper. The proposed system is designed with distributed LoRaWAN architecture. Distributed LoRa gateways and network servers record data transmissions in tangle network to make LoRa data traceable and avoid single point of failure. In addition, a secure LoRa data ledger (SLDL) using digital signature algorithm and symmetric-key encryption is designed to defend against malicious gateway attacks, eavesdropping, etc. The proposed system is implemented and validated using DAG-based IOTA platform. The results demonstrate that the prototype system can achieve nearly up to 100 transaction per second (TPS) of throughput and about 1.3 second latency, which is about 90% reduction than existing blockchain-based solutions. As a result, the proposed DAG-based LoRaWAN system is an effective solution to ensure the security and efficiency of large-scale LoRa networks.