Performance Evaluation of Slotted ALOHA based IoT Networks under Asymmetric Traffic

Abstract

LoRaWAN is a highly promising technology for wide access networks and sensor applications. It is considered one of the top alternatives for the networking in the Internet of Things thanks to its low cost and its low energy consumption. It has been shown that using Slotted ALOHA at the MAC layer achieves satisfactory performance at a low implementation complexity and cost. In such a network, not all sensors are of the same type, so the traffic they produce is asymmetric. However, to this day, the performance of this protocol under asymmetric traffic conditions in a LoRaWAn environment has not been studied. This paper studies a Slotted-ALOHA-based LoRaWAnnetwork under asymmetric traffic, with a mixture of lightly, medium and heavy-loaded stations. Network performance is studied via extensive simulation results by using delay and throughput as performance metrics. Finally, the protocol's performance under asymmetric traffic in the LoRaWAn environment is extensively discussed in the light of the above simulation results and major conclusions are extracted.