SpecsModelExploreRequirements
SpecsModelExploreRequirements
MQTT Broker
Overview
Guide
MQTT topics
Twin streams
Links and Communications
IDproduct.ingestion.mqtt_broker
DescriptionMulti-tenant MQTT broker with TLS and authentication.
Keymqtt_broker
Typemicroservice:broker
Statusactive
TeamIngestion
Owner
ingestion@iotgateway.example
TechnologiesEMQX/Mosquitto (MQTT), MQTT, TLS, Redis
Tags
Table of contents
Guide
MQTT Broker
Internal structure
Components
Connection lifecycle
Authentication
Session
Pub/Sub
QoS at a glance
Related workflows
MQTT topics
Links and Communications
Requirements

Attributes

max_connections1M
protocolMQTT 5.0
qos0,1,2

Guide

MQTT Broker

The MQTT Broker is where the fleet physically connects. It terminates mutual-TLS sessions, authenticates each device against its certificate, keeps per-client session and QoS state, and routes published messages between devices and the cloud.

Why MQTT

MQTT is built for constrained, intermittently connected devices: tiny frames, persistent sessions, QoS levels for at-least-once / exactly-once delivery, and last-will messages for crash detection. That maps directly onto a fleet of field devices on flaky networks.

Internal structure

Could not build diagram for model "example-iot".

Components

TLS Listener

Mutual-TLS endpoint that authenticates each device on connect.

Topic Router

Matches published messages to subscribers by topic filter.

Session Store

Persists client sessions, subscriptions and in-flight QoS state.

Connection lifecycle

Handshake

The device opens a TCP connection and the TLS Listener performs a mutual-TLS handshake, presenting the server cert and verifying the device’s client certificate against the trust chain.

Authentication

The certificate fingerprint is checked against Device Management to confirm it maps to an active device. Rejected devices are disconnected immediately.

Session

The Session Store either resumes a persistent session or creates a clean one, restoring any in-flight QoS 1/2 messages.

Pub/Sub

The Topic Router fans inbound telemetry to subscribers and delivers cloud commands down to the device’s subscribed topics.

QoS at a glance

Fire-and-forget. Used for high-frequency, loss-tolerant telemetry where the next sample makes the last one irrelevant.

Related workflows

The broker carries every device interaction, so it participates in all of the platform’s core flows.

The inbound telemetry that feeds alerting arrives here first:

Outbound commands are delivered to devices over the broker:

A newly provisioned device’s very first session is established here:

Firmware rollouts use the broker for both command delivery and progress telemetry:

MQTT topics

Links and Communications

1 outgoing link · 3 workflows · 2 consumers · 2 producers

Outgoing Links(1)

Target objectLabelLink typeRelationRaw idRequiredDescription
Command Router

example-iot.product.ingestion.command_router

microservice:service
routes commands to—linksproduct.ingestion.command_router——

Consumers(2)

ConsumerChannels
MQTT Publisherproduct.edge.edge_agent.mqtt_publisher

  • Device commands

    commands

Stream Processorproduct.processing.stream_processor

  • Device telemetry

    telemetry

Producers(2)

ProducerChannels
Command Routerproduct.ingestion.command_router

  • Device commands

    commands

MQTT Publisherproduct.edge.edge_agent.mqtt_publisher

  • Device telemetry

    telemetry

Related Workflows(3)

WorkflowModelParticipant idParticipant label
Command dispatch

commands.dispatch

example-iotproduct.ingestion.mqtt_brokerMQTT broker
Device provisioning

device-lifecycle.provisioning

example-iotproduct.ingestion.mqtt_brokerMQTT broker
Telemetry to alert

telemetry.alert-pipeline

example-iotproduct.ingestion.mqtt_brokerMQTT broker

Requirements