Click on the “Embedded Application Research Institute” above, and select “Top/Star Official Account“ Useful Resources Delivered First Hand! Source | Embedded Application Research Institute Compiled & Formatted | Embedded Application Research Institute In the development of IoT-related applications, MQTT is used to some extent. The following open-source project is an interface I encapsulated based on … Read more
Background Keep alive is part of the variable header in the CONNECT message. We have mentioned that the Broker needs to know whether the Client has disconnected abnormally to send the last will message. In fact, the Client also needs to quickly detect if it has lost the connection to the Broker in order to … Read more
1. Review: Overview of ROS Communication Mechanism & Similarities and Differences with MQTT Communication Overview of ROS Communication Mechanism The main communication mechanisms in ROS are as follows: 1. Topics ○ Publish/Subscribe Model: In this communication method, nodes can publish messages to a topic or subscribe to a topic to receive messages. This method is … Read more
Introduction: The First Groundbreaking Product to Introduce QUIC to MQTT In the recently released version 5.0, EMQX has innovatively introduced QUIC support. QUIC is the underlying transport protocol for the next-generation internet protocol HTTP/3. Compared to TCP/TLS protocols, it effectively reduces connection overhead and message latency, providing a flexible and efficient transport layer for modern … Read more
Background Previously, we discussed how to publish messages and their corresponding packets; now let’s look at how the packets for subscribing to a topic are structured. SUBSCRIBE – Subscribe to a Topic The client sends a SUBSCRIBE packet to the server to create one or more subscriptions. Each subscription registers one or more topics of … Read more
Author：Nanhai District Dali Town Junior High School, Foshan City, Guangdong Province Zhang Quan, Ling Yujie, Xie Hanzhe This article is sourced from “Invention and Innovation” May 2023 Junior High School Edition We found that homeroom teachers and subject teachers have many repetitive and mechanical tasks, such as: every day the homeroom teacher conveys messages from … Read more
Data packets sent by IoT smart devices must be encapsulated by the corresponding protocol at each layer. With the rapid development of Internet of Things (IoT) technology, most smart devices’ communication modules support various network communication protocols such as TCP, UDP, MQTT, CoAP, HTTP, and LwM2M, which include both transport layer and application layer protocols, … Read more
Distributed MQTT Broker Server The distributed MQTT Broker server is a message broker based on the publish/subscribe model. It supports load balancing and data synchronization across multiple nodes to provide high availability and scalability for MQTT messaging services. Here is a detailed explanation of the distributed MQTT Broker server: 1. Definition and Functionality Definition: The … Read more
Let’s dive into MQTT, how to ensure its security, and examples of the protocol to see how it has rapidly gained popularity in the IoT field. In today’s world, there are billions of smart devices. Imagine if these devices were all interconnected and could communicate with each other like their users, forming a global network. … Read more
MQTT Packet Structure In the MQTT protocol, an MQTT packet consists of three parts: Fixed Header, Variable Header, and Payload. (1) Fixed Header. Present in all MQTT packets, indicating the packet type and group class identifier. (2) Variable Header. Present in some MQTT packets, the packet type determines whether the variable header exists and its … Read more