The Chariot MQTT Server – Understanding and Utilization

An MQTT server uses a machine-to-machine protocol called Message Queuing Telemetry Transport (MQTT). This protocol is designed to facilitate lightweight publish/subscribe message transportation for low-bandwidth, high-latency networks. It minimizes network bandwidth and resource requirements while ensuring reliability by keeping packet headers as small as possible.

MQTT servers are utilized for a variety of IoT devices, platforms, and operating systems. Cirrus Link Solutions offer an Open Virtualization Format (OVF) and OASSyS MQTT 3.1.1. compliant solution – the Chariot MQTT Server. This solution is an open standard for packaging and distributing virtual appliances, which is essential when running a private on premise or cloud application.

Setting up an MQTT server scheme to handle your pub/sub messaging needs can bring powerful benefits to your process: This solution saves development time, increase your scalability, and allows your information to be distributed quickly and efficiently. The most important benefit would be in the drastically reduced network bandwidth consumption.

Cirrus Link Solutions Chariot MQTT Server offers enhanced features, such as:

  • Web Based Administration 
  • TLS Security
  • Username/Password Authentication
  • Access Control Lists (ACLs) user authentication
  • Available as an Amazon Machine Image (AMI) used to create a virtual machine within the Amazon Elastic Compute Cloud (“EC2”)

How the MQTT Server Works

An MQTT system consists of multiple clients—publishers or subscribers—that are configured to communicate with a server, also known as a MQTT broker. There are four primary MQTT Control Packets that the client and server use to communicate:

  • Connect—The first packet sent from the client to the server must be a Connect packet in order to establish a connection.
  • Disconnect—The final packet sent from the client to the server that indicates why the connection is being closed.
  • Subscribe—A subscribe packet is always sent from the client to the server to create one or more topic subscriptions.
  • Publish—A publish packet can be sent from the client to the server, usually transporting an application message, or from the server to a client which has subscribed to the respective topic.

A client’s connection to the broker always contains a specific Quality of Service (QoS) measure. There are three options:

  • At most once—A message is sent once and only once.
  • At least once—After a message is sent, the client sends a response acknowledging message received.
  • Exactly once—A two-level confirmation between the broker and the client confirming the message is received and only delivered once.

For real time SCADA applications the first option is used, since when a control is published the operator wants it to be delivered now, not some time later if there is a communication disruption.

Examples of MQTT Server Utilization

MQTT server systems are used to maintain messengers, Internet of Things sensors (IoTs), danger alert systems, and much more. An MQTT server can be leveraged to deliver data to predict electricity consumption needs by monitoring electricity units, connect factory process data to cloud services for machine learning and analytics, and even reduce latency when sending messages on social networks. Most commonly, MQTT servers are used in industrial computer systems.

Supervisory Control and Data Acquisition or SCADA generally refers to the industrial computer system that monitors and controls a process. SCADA will monitor substations, transformers and other electrical assets, in the transmission and distribution of electrical utility’s elements. SCADA systems typically control large amounts of information over assets separated geographically over thousands of miles. The most efficient use of bandwidth in these large-scale applications is handled with the Chariot MQTT Server.


The Chariot MQTT Server is a functional replacement for MQTT Distributor Module for larger scale deployments with use of the Inductive Automation Ignition Platform.  Like the Ignition platform, this Cirrus Link Solutions offering comes with a two-hour re-settable trial period. It can also be set up with a license key from Cirrus Link Solutions to enable it permanently once purchased.

To try the free trial of the Chariot MQTT Server software and tutorial go here!


More information including installation instructions follow the links below.

·       Chariot MQTT Server Installation   –  Step by step instructions to install Chariot MQTT Server in Amazon Web Services (AWS) EC2 or on premises in a Virtual Machine

·       Chariot MQTT Server Configuration  –  Configuration guide for the Chariot MQTT Server

·       Chariot MQTT Server Tutorials/How-to’s  – All tutorials and how-to’s for the Chariot MQTT Server


Cirrus Link Solutions