Activation of LoRaWAN End Devices by Using Public Key Cryptography

Abstract

This paper aims to design a new process to assign root keys to the devices in Long Range Wide Area Network (LoRaWAN) by using Public Key Cryptography (PKC). This process is used to propose a new activation method called Public Key Over the Air Activation (PK-OTAA). The feasibility of the proposed method is also evaluated scientifically via experiments. The new activation method allows a device to get the root keys dynamically and for them to be replaced at will. However, PKC requires longer keys to get equivalent cryptographic strength to a symmetric encryption scheme. This increased key size in turn requires more processing power to use, thus increasing battery consumption. The feasibility of the new method is evaluated based on the increase in power usage since Internet of Things (IoT) devices are usually battery powered. It has been shown that by sacrificing very small portion of the energy available in the battery; a more flexible and secure key distribution scheme is integrated in LoRaWAN.