LoRaWAN is an open protocol standards driven by the LoRa Alliance. A proven and popular technology in the Low Power WAN (LPWAN) arena, LoRaWAN has been designed from ground up to optimize LPWANs for IoT applications that require long range, low power, high capacity and low implementation cost. LoRaWAN is based on chirp spread spectrum (CSS), an advanced spread spectrum modulation technology which has been used in military and space communication for decades because of its long range and robustness to interference.
LoRaWAN™ networks typically are laid out in star-of-stars topology in which gateways relay messages between end-devices and the central network server at the backend. Gateways are connected to the network server via standard IP connections while the end-devices use single-hop LoRa™ communication to one or many gateways. All communication is generally bi-directional, although uplink communication from an end-device to the network server is expected to be the predominant traffic.
In a LoRaWAN, end nodes are not associated with a specific gateway. Instead, data transmitted by a node is typically received by multiple gateways. Each gateway will forward the received packet from the end-node to the cloud-based network server via some backhaul (e.g. LTE 4G). The intelligence and complexity is pushed to the network server, which manages the network and filters redundant received packets, performs security checks, schedules acknowledgments through the optimal gateway, performs adaptive data rate, etc.