Academy for LoRaWAN®

The starting point of a network built on the LoRaWAN standard is an end device that transmits uplink messages to gateways on the network, which then forwards those messages to the network server. The network server is where the LoRaWAN networking protocol terminates, and where data handling takes place.

The network server is responsible for:

• The network server is responsible for:
• Routing/forwarding messages to the application server
• Selecting the best gateway for downlink messages
• Message acknowledgements
• Removing duplicate messages (if a message is received by multiple gateways)
• Encrypting and decrypting messages sent to and from end devices

• Wireless security
• Device identification
• Media Access Control (MAC) commands
• Management of the Adaptive Data Rate
• (ADR) of individual end devices by setting end device data rates and power
• consumption parameters
• Management of the end device transmit
• (TX) frequency and receive window (RX) timing.
• Management of the security of each message via sessions keys and frame counters
• Management of downlink messages:
  • Selecting the gateway for downlink transmissions based on Received Signal Strength Indicator (RSSI) and Signal-to-Noise Ratio (SNR) as received by the gateway
  • Monitoring and tracking gateway usage to avoid message collision.  In the case of dynamic channel plans, the network server also monitors the duty cycle used by the gateway

When developing and prototyping your IoT solutions, you can use Semtech’s Network Server free of charge. With this free service, you can connect up to three gateways and up to 10 end devices. The Semtech Network Server uses the ChirpStack open-source project.  In addition, most public operators offer a free or inexpensive option. Check with your local providers to see what is available in your region.