This talk will demonstrate techniques for decoding the LoRa PHY layer and will introduce gr-lora, an open source implementation of the protocol. LoRa is a Low Power Wide Area Network (LPWAN), an emerging class of wireless technology optimized for embedded and IoT applications. LoRa is unique because it uses a chirp spread spectrum modulation that encodes data into RF features more commonly encountered in RADAR systems. LoRa is also designed to operate in unlicensed ISM frequency bands, both avoiding costly spectrum licensing requirements and democratizing long-range network infrastructure to consumers and new commercial operators alike. After briefly introducing the audience to LPWANs, I will walk through the SDR and DSP techniques required to demodulate and decode LoRa packets. In addition I will introduce gr-lora, an open-source implementation of the PHY that can be leveraged to design LoRa security test tools and drive future research.