Usage

Process

Figure 1 Broadcast communication sequence diagram

Procedure

1. A device initiates connection authentication. For details about how to set authentication parameters, see MQTT Device Connection Authentication.
2. After the device is authenticated, it initiates a broadcast topic subscription. The broadcast topic must be prefixed with $oc/broadcast/. Example:

   $oc/broadcast/test  

3. The application server delivers a broadcast message (see Broadcasting a Message) and specifies the topic name and message content.

   POST https://{Endpoint}/v5/iot/{project_id}/broadcast-messages
   Content-Type: application/json
   X-Auth-Token: ********
   
   {
     "topic_full_name" : "$oc/broadcast/test",
     "message" : "eyJhIjoxfQ=="
   }

   

   The topic must be prefixed with $oc/broadcast/, and the message content must be encoded using Base64.

4. The device receives the broadcast message. Example message:

   Topic: $oc/broadcast/test  
   Data content
   {"a":1}