2 - Sending Messages
Messages sent from an end device to a network server via one or more nearby gateways are referred to as uplinks.
In this book, you learn the rules and best practices to follow when sending uplinks from your end device using the LoRaWAN® 1.0.4 specification.
Introduction
Messages sent from an end device to a network server via one or more nearby gateways are referred to as uplinks.
In this book, you learn the rules and best practices to follow when sending uplinks from your end device using the LoRaWAN® 1.0.4 specification.
Type of Uplinks
Uplink messages may include one or both of the following types of information:
Application data used to transmit readings and other information from the end device. This type of data is specific to the use case your end device implements. Examples include temperature readings from a sensor, or a message to confirm that a valve has been closed.
MAC commands used for LoRaWAN® network administration.
An uplink message also contains bit fields (which are always sent, set to either on or off), that send the following information:
Confirmation of receipt of a confirmed downlink message received from the network server. Confirmed downlinks are a type of downlink that requires a response from the end device.
Additional fields used in adaptive data rate (ADR) and Class B operations.
It is possible for a message to carry neither application data nor MAC commands. Examples include when the end device sends an empty uplink for the sole purpose of receiving a downlink, responding to a confirmed downlink without accompanying data, and informing the network server it is moving to Class B mode.