The MQTT feed type in ArcGIS Velocity subscribes to and consumes messages from an externally accessible MQTT broker. MQTT stands for Message Queuing Telemetry Transport. It is a basic messaging protocol for publishing and subscription for constrained devices and low-bandwidth, high-latency, or unreliable networks. The design principles are to minimize network bandwidth and device resource requirements while ensuring reliability and assurance of delivery.
For more information about MQTT, see the MQTT protocol FAQ.
Examples
- A data analyst wants to ingest their sensor data through an MQTT broker.
- A transportation department configures an MQTT feed to consume vehicle positions and attribute information.
Usage notes
- The MQTT broker must be externally accessible on the internet.
- For SSL/TLS broker connections, prefix the hostname with ssl://.
- For nonSSL connections, prefix the host name with tcp://.
After configuring feed connection parameters, see Configure input data to learn how to define the schema and the key parameters.
Parameters
Parameter | Description | Data type |
---|---|---|
Host | The host name of the MQTT broker. For nonSSL connections, prefix the host name with tcp://. For SSL/TLS broker connections, prefix the host name with ssl://. | String |
Port | The port of the MQTT broker. | Integer |
Username | The user name for the MQTT broker. This parameter is only used if the MQTT topic specified is secured. | String |
Password | The password for the MQTT broker. This parameter is only used if the MQTT topic specified is secured. | Password |
Client ID | The client ID Velocity will use to connect to the broker. Note:Many brokers require a unique client ID for every connected client. It is recommended that you not reuse the same client ID specified in other feeds or applications. If a client ID is not specified, the running feed will use the item ID as the client ID. | String |
Topic | The MQTT topic from which Velocity will consume messages. | String |
Quality of Service Level | Specifies the quality of service (QoS) level, which defines the guarantee of delivery for a specific message.
| Integer |
Considerations and limitations
The MQTT broker must be externally accessible on the internet.