1. Introduction

RTI® Routing Service MQTT Adapter is a plugin for RTI Routing Service which enables communication between MQTT and DDS applications.

Using Routing Service MQTT Adapter, Routing Service can act as an MQTT Client, connect to an MQTT Broker, publish MQTT Messages, and subscribe to MQTT Topics published by other MQTT applications.

Users can configure Routing Service to route data between multiple DDS Domains and MQTT Brokers, enabling all DomainParticipants in a DDS Domain to exchange data with all MQTT Clients connected to an MQTT Broker, as shown in figure Figure 1.1.

Figure 1.1 DDS/MQTT Integrated System Architecture

Routing Service MQTT Adapter performs automatic convertions between MQTT Messages and DDS Samples of two “generic” DDS Types, which model the metadata (e.g. topic, qos, retained flag, etc.), and the opaque payload of an MQTT Message.

DDS applications can use these types to exchange data with MQTT applications. Optionally, Routing Service’s Transformation API can be used to implement custom transformations between the MQTT payload, and DDS Types used by the system.

Routing Service’s Processor API can also be used to implement custom mappings between DDS and MQTT data streams, for example, to automatically map different MQTT Topics into Instances of the same DDS Topic.