MQTTv5 CONNECT and CONNACK Messages -Overview

The MQTT CONNECT and response messages (CONNACK) have been greatly enhanced in MQTTv5 with the addition of the properties field. The properties field allows for a large increase in the information that can be exchanged between client and server on connection establishment compared to MQTT v3.1.1. For example it is now possible to restrict the maximum message size the server will send to the client by telling the server what message size the client will accept. It is also possible to learn what restrictions the broker imposes on the client by examining the Connection acknowledgement message. The purpose of this

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Using HTTP APIs For IOT -Beginners Guide

Many of the APIs today are Web API’s designed to access web services like Facebook ,Twitter etc. Because of their widespread use most IOT services (AZURE,AWS,Bluemix)  also support http based APIs. To understand and use an http API you will need a reasonable understanding of the following:

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JSON Basics For Beginners-With Examples and Exercises

When sending and receiving data in IOT applications and APIs you will encounter JSON formatted data. Having a good working knowledge of JSON, and how to create and use JSON data will be very important in developing IOT applications. The tutorial is split into two sections. The first section we look at creating JSON data and in the second section we look at converting JSON data into JavaScript objects and extracting values from the data.

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Using cURL for Testing IOT Applications

The http protocol is the main protocol used on the web, and because of its widespread adoption it is also used in IOT applications. Many IOT applications like the Thingsboard Dashboard support both http and MQTT. In this tutorial we will start with a general introduction to cURL and show examples of using cURL to get and POST data.

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Understanding And Using MQTT v5 Request Response

Web Applications have a direct connection between the sender and receiver. The sender is the client (web browser) and the receiver is the server. They implement a command response message flow were the client(browser) makes a request and the server responds and there is a direct connection between client and server.

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MQTT v 5.0 New Features Overview

MQTT v5 introduced many new features and changed how some existing features work. In this tutorial I will be covering all of these features with brief examples, and also in many case, links to detailed examples and videos.

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IPv6 Explained for Beginners

IPV6 has been developed to replace IPV4 which is running out of addresses. Although it has been around almost 10 years it is still not widely deployed and supported. However adoption rates are increasing rapidly and IPv6 traffic crossed the 10% threshold in February 2016 (wiki) .

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