The cost of reliable uplink communication in large scale LoRaWAN

Reliability is one of the promised features by the LoRaWAN technology. In this paper, we investigate the cost of reliable uplink communication in terms of latency and energy-consumption in a large scale LoRaWAN. We resort to markov chain to model latency and energy consumption for both class A and class B LoRaWAN end-devices. Results prove that reliable uplink communication in large scale LoRaWAN considerably affects latency and energy consumption. For example, in a best case scenario of 1000 end-devices, an uplink packet requires an average of $4620s$ to be acknowledged, and $124J$ of energy consumption.