A Consistent Address Allocation Algorithm Mitigating Address Conflict for Large-Scale LoRa-Enabled IoT Networks

LoRa is a strong enabling technology for outdoor IoT (Internet of Things) networking. With LoRa networks increasingly getting bigger to provide wider coverage and indeed internet working of multiple individual LoRa networks, LoRa terminal devices are prone to address conflict, namely, different terminal devices have the same device ID or address. On the other hand, when a LoRa node is reconnected to the LoRa network after temporary disconnection it might be allocated a different device ID rendering application-layer disruption. We call this address inconsistency. These two issues are less concerned in the research community but are critically important in practice. This paper proposes an address allocation algorithm for LoRa terminal devices to tackle the above two challenges. The proposed algorithm increases the randomness of the generated addresses by changing the way the seed is chosen and by introducing a new random number generator called xorshift. An address registry is also introduced to further check whether the generated address has been used on one hand and to make sure the same address is assigned to a reconnecting node. Both experimental and simulation results have shown the effectiveness and efficiency of the proposed algorithm.