  Long Range Wide Area Networks (LoRaWAN) is an open medium access control
(MAC) layer technology devised for the long range connectivity of massive
number of low power network devices. This work gives an overview of the key
aspects of LoRaWAN technology and presents results that we achieved via
extensive evaluation of Class A LoRaWAN devices in different network settings
using the state-of-the-art network simulator (NS-3). At first, we focus on a
single device and its mobility. We further undertook evaluations in an extended
network scenario with a changing number of devices and traffic intensity. In
particular, we evaluate the packet delivery ratio (PDR), uplink (UL)
throughput, and sub-band utilization for the confirmed and unconfirmed UL
transmissions in different environments. Our results give new insights for
future efforts to optimize the LoRaWAN performance for different large scale
Internet of Things (IoT) applications with low power end devices.
