LoRaWAN for Smart City IoT Deployments: A Long Term Evaluation LoRaWAN is a LowPowerWide Area Network (LPWAN) technology designed for Internetof Things (IoT) deployments; this paper presents experiences from deploying a cityscale network across Southampton, UK. This network was deployed to support an installation of air quality monitors and to explore the capabilities of . This deployment uses a mixture of commercial offtheshelf gateways and custom gateways. These gateway locations were chosen based on network access, site permission and accessibility, and are not necessarily the best locations theoretically. Over 135,000 messages have been transmitted by the twenty devices analysed. Over the course of the complete deployment,     72 . 4     of the messages were successfully received by the data server. Of the messages that were received, 99 were received within 10   s    of transmission. We conclude that is an applicable communication technology for cityscale air quality monitoring and other smart city applications.

Examining Carrier Sense Multiple Access to Enhance LoRa IoT Network Performance for Smart City Applications Low Power Wide Area Network technology is a promising solution to realize dense network deployment. Among those technologies, Long Range (LoRa) stands out and is actively being deployed worldwide. The key to its widespread is that it is designed from bottom up to optimize battery lifetime, capacity, long communication range and cost. Hence, this makes LoRaWAN an excellent choice for a massive portion of IoT applications deployed in smart cities. LoRaWAN adopts a fairly simple AlohaLike MAC protocol which simplifies the network operation and preserves battery lifetime. However, the unsynchronized transmission fashion degrades the network throughput as the traffic load increases. Therefore, we investigate the performance and limitations of using a more advanced MAC protocol such as CSMA. We ran several simulation campaigns. First, conventional LoRaWAN network performance is analyzed. Then, introducing a new aspect to the proposition of CSMA in LoRa networks, we inspect the limitations of an enddevicexe2x80x99s sensing range upon the development of the suggested CSMACA variant. Finally, we examine the network performance enhancement experienced when using a more advanced protocol such as CSMA for several realistic smart cities IoT applications deployment.