Author: steve
Updated:May 13, 2020 By steve
Paho Python MQTT Client – Publish With Examples
In this tutorial we will look at how you publish messages using the Paho Python MQTT client. We will use an example python script to publish messages, process the publish acknowledgements and examine QOS (quality of service) settings. To publish a messages you use the publish method of the Paho MQTT Class object. The publish method accepts 4 parameters. The parameters are shown below with their default values.
Updated:November 30, 2019 By steve
Understanding The Domain Name Structure
To understand the domain name structure you really need to understand the problem the structure was meant to solve. The Domain Name Structure and Domain Name System were developed to organise and find the IP addresses of Computers on large distributed networks.
Updated:July 17, 2020 By steve
Understanding HTTP Basics
HTTP stands for hypertext transfer protocol and is used to transfer data across the Web. It is a critical protocol for web developers to understand and because of it widespread use it is also used in transferring data and commands in IOT applications. The first version of the protocol had only one method, namely GET, which would request a page from a server. The response from the server was always an HTML page.- Wiki To give you an idea of how simple the HTTP protocol started out take a look at the Original specification which was only 1 page.
How to Use Nslookup – Beginners Guide
nslookup is a network administration command-line tool available for many computer operating systems. It is used for querying the Domain Name System (DNS) to obtain domain name or IP address mapping information .- Wiki
Understanding DNS – Beginners Guide to DNS
DNS (Domain Name System) is one of the most important technologies/services on the internet, as without it the Internet would be very difficult to use. DNS provides a name to number (IP address) mapping or translation, allowing internet users to use, easy to remember names, and not numbers to access resources on a network and the Internet.
TCP/IP Ports and Sockets Explained
On a TCP/IP network every device must have an IP address. The IP address identifies the device e.g. computer. However an IP address alone is not sufficient for running network applications, as a computer can run multiple applications and/or services. Just as the IP address identifies the computer, The network port identifies the application or service running on the computer. The use of ports allow computers/devices to run multiple services/applications. The diagram below shows a computer to computer connection and identifies the IP addresses and ports.
The TCP/IP Model and Protocol Suite Explained for Beginners
Any one starting to learn about computer networking will be faced with learning about the OSI and TCP/IP networking models, and the TCP/IP protocol suite. In this tutorial we will look at networking protocol models, and explain how and why they are structured into layers. We will then look at the most common protocol suite, the TCP/IP protocol suite and the 4 layer model.
Beginners Guide to Bluetooth
Bluetooth is a wireless networking protocol (like WIFI) designed to quickly and automatically connect devices like printers, PDAs, Cameras etc to computers and to each other without wires. Common Bluetooth applications are: Connecting mobile phones to each other to exchange pictures,ring tones, music etc Connecting computer peripherals like mice, keyboards, printers etc to a computer. Connecting headsets to mobile phones for hands free operation (Bluetooth car kits)
Binary Numbers Explained – Beginners Guide
In my experience of teaching networking many students struggle with IP addresses because they lack an basic understanding of binary numbers. An understanding of binary numbers,the binary system, and how to convert between binary and decimal is essential for anyone involved in computers, coding, and networking.
Understanding and Using The Hosts File-Beginners Guide
What is the hosts file? and What is it used for?– The hosts file performs a name to IP address mapping and was used on early computer networks for name resolution before DNS was developed. The hosts file is still present on computer systems (windows,Linux, MAC), tablets (e.g. android) etc and can be very useful for testing purposes. The hosts file is a simple text file that can be edited with a text editor like notepad. However it is important to note the hosts file doesn't have a file extension like .txt.