LoRaWAN 1.0.4 Specification in Depth For End Device Developers

MAC commands are used to manage the network. There are 13 types of commands, each having a request command and an answer command. There are ten request commands that the end device may receive from the network server, each requiring processing, the outcome of which may require an action to be taken, and a possible answer to be sent. There are three answers that the end device may receive from the network server in return from requests it has initiated. Sending answers and requests from the end device was covered in the section Sending MAC Commands of the Sending Messages Book.

MAC commands can be received individually or in a group of concurrent MAC commands. All MAC commands begin with a single octet containing a Command Identifier (CID). This CID indicates which MAC command type follows in the subsequent octets. The length of the subsequent octets depends on the type of MAC command, as identified in the preceding CID. MAC commands are received in the same way, regardless of whether they are a request or answer.

The diagram below shows the structure of three different MAC command requests and illustrates how each command can have a different length. As mentioned, all MAC commands start with a CID octet. The LinkCheckReq MAC command contains only the CID octet and has no payload. DutyCycleReq contains two octets in total, the CID octet followed by a single octet containing data related to the request. LinkADRReq has a total of five octets, the CID octet followed by four octets containing the data.

The subsequent sections contain details about each MAC command request or answer the end device may receive. The table below lists each command and links to each section.