Design And Implementation Of Message Push Cluster System Based On MQTT

With the development and rise of the Internet of Everything,the message transmission between Io T devices has become a new demand due to the different network environments.Currently,MQTT is one of the most common protocols for this type of scenario.The MQTT protocol has small data packets and high bandwidth utilization,which is more suitable for networking applications.Based on this,this thesis studies and designs a message push cluster system based on MQTT for the specific application scenarios of the Internet of Things.As part of the company's Io T cloud platform project,the system aims to serve the Io T online platform,solve problems found in practical applications,and optimize the ease of use of the message push system in specific application scenarios.Specifically,the system is responsible for establishing a stable MQTT connection with the external terminal device,processing the publish and subscribe request of the topic message,and connecting with the internal application microservice to provide a message transfer mode based on the publish subscription mode for the platform micro service call.Based on the above functions,the cluster solution is designed to meet the requirements of high availability and scalability,and to design security solutions to ensure system security and user data security.The specific work content and technical solutions are as follows:(1)Design and implementation of the basic push function.Analyze the meaning of each field of the message in the MQTT protocol and the specific process of message push,and design the logic flow of establishing connection,publishing,subscription and other functions.(2)Research on multi-node clustering scheme of MQTT Broker.Based on the research of the open source project Mosquitto,the system is designed to be decentralized distributed cluster architecture,and it is packaged and deployed by Kubernetes and Docker virtualization technology to solve the problems of system deployment in cluster deployment,cluster expansion,and node management.Improve the utilization of computing power of each node to meet the performance requirements of the system.(3)Research on access security scheme of cluster system.Access security is guaranteed from three aspects: data encryption,identity authentication,and access control.First,thetransmission is encrypted by SSL/TLS before the MQTT connection is established.Secondly,the identity of the client is verified by the authentication chain when the connection is established.The action of posting/subscribing to a connection after it is established is controlled by ACL permissions based on the subject.Finally,the status,connection number,and session information of all nodes in the cluster are counted and provided to the front-end monitoring service.(4)Perform functional tests and performance tests on the entire system to verify the results of the research and technical solutions.Through the functional test,the logic flow of the main function modules of the system is detected.Through the performance test,the performance of the system in a high concurrent environment is detected.The system was successfully deployed in the actual application environment.After a period of trial operation and the performance tests showed that the message push cluster system achieved the expected results in performance requirements and business function requirements.However,due to the variety of online platform users of system services,the application scenarios are complex and changeable,and the system needs to discover and clarify problems through actual business applications,so as to improve and supplement the functions.