Attack-aware Synchronization-free Data Timestamping in LoRaWAN

Low-power wide-area network technologies such as long-range (LoRaWAN) are promising for collecting low-rate monitoring data from geographically distributed sensors, in which timestamping the sensor is a critical system function. This article considers synchronization-free approach to LoRaWAN uplink based on signal arrival time at gateway, well matches LoRaWAN’s one-hop star topology and releases bandwidth transmitting timestamps synchronizing end devices’ clocks all times. However, we show that this susceptible frame delay attack consisting of malicious collision delayed replay. Real experiments can affect devices large areas up about 50,000, m 2 . In broader sense, threatens any functions requiring timely deliveries frames. To address threat, propose LoRaTS gateway design integrates commodity low-power software-defined radio receiver track inherent frequency biases devices. Based an analytic model LoRa’s chirp spread spectrum modulation, develop processing algorithms estimate with high accuracy beyond achieved by default demodulation. The accurate bias tracking capability enables detection introduces additional biases. We also investigate implement more crafty uses advanced apparatuses eliminate attack, pseudorandom interval hopping scheme enhance our approach. Extensive effectiveness deployments real affecting factors temperature variations.