You can configure the mosquitto broker using a configuration file. The default configuration file is called mosquitto.conf and it is used by the mosquitto broker when started as a Linux daemon or Windows service.
Continue readingAuthor: steve
DNS Zones and Zone Files Explained
DNS is comprised logically of Domains but physically of zones. A domain is a logical division of the DNS name space whereas a zone is physical, as the information is stored in a file called a zone file.
Continue readingUsing The Mosquitto_pub and Mosquitto_sub MQTT Client Tools- Examples
The Mosquitto_pub and Mosquitto_sub client utilities comes with the Mosquitto package, and are excellent tools for conducting quick tests and troubleshooting.. In this tutorial we are going to be looking at some examples of using these tools for publishing and subscribing.
Continue readingMQTT Sensors and Network Traffic Observations
MQTT is primarily a M2M protocol. It was originally designed for send sensor data from a remote oil field. As the number of sensors increases the amount of network traffic generated by sensors will increase dramatically and depending on the transport it could prove expensive. It will be important to understand this sensor traffic and how it can be reduced.
Continue readingHost Name Resolution Methods Explained
On computer and home networks when you type an Internet address into a web browser the web browser needs to convert that web address into an IP address. To do that it uses the the name resolution processes provided by the host machine. There are several ways that the host machine can resolve a domain name. The main ones are:
Continue readingDNS Lookups Explained
In this tutorial we will examine what happens when you use DNS to lookup or resolve a domain name to an IP address. We look at how DNS lookups work, and the exact process involved when looking up a domain name. We follow the client DNS query as it is processed by the various DNS servers in the response chain. Before we start it might be useful to compare DNS name resolution with a standard question and answer that takes place in everyday life.
Continue readingPaho Python MQTT Client-Understanding The Loop
When writing code using the Paho Python client you would have had to use the loop() function . In this tutorial we will look at what it does, and why it is necessary. When new messages arrive at the Python MQTT client they are placed in a receive buffer. The messages sit in this receive buffer waiting to be read by the client program.
Continue readingMosquitto MQTT Bridge -Usage and Configuration
A MQTT bridge lets you connect two MQTT brokers together. They are generally used for sharing messages between systems. A common usage is connect edge MQTT brokers to a central or remote MQTT network. The Mosquitto broker (server) can be configured to work as an MQTT bridge.
Continue readingUnderstanding the MQTT Protocol Packet Structure
In this tutorial we will take a more detailed look at the MQTT protocol, and how MQTT messages or packets are formatted. We will be looking at: The MQTT message format. The MQTT message header Message fields and coding Control Message coding example
Continue readingUsing MQTT Over WebSockets with Mosquitto
What is Websockets and How it Works? WebSocket is a computer communications protocol, providing full-duplex communication channels over a single TCP/IP connection. Wiki It is closely associated with http as it uses http for the initial connection establishment.. The client and server connect using http and then negotiate a connection upgrade to websockets, the connection then switches from http to websockets. The client and server can now exchange full duplex binary data over the connection. Video -MQTT Over Websockets Explained Why Use MQTT over Websockets? MQTT over Websockets allows you to receive MQTT data directly into a web browser.
Continue reading