Design And Implementation Of The MQTT-based Message Pushing Cluster System

With the continuous improvement of Internet technology and hardwaremanufacturers technology, mobile devices and smart terminal represented by iPad,iPhone and the Android phones have made a significant development in recentyears.The number of their users is growing explosively. More and more people,especially the younger generation use the intelligent Terminal instead of the traditionalPC terminal to obtain information.In order to meet the requirments of timeliness ofaccesses of information, power consumption, as well as the network environment inpractical application, we should replace the traditional pull way with the push way todeliver messages. MQTT（Message Queuing Telemetry Transport）is a messagingprotocol just designed for the situation. MQTT protocol has small size, low powerconsumption, small packets, and support all platforms. It can effectively send theinformation to the mobile application containing one or more recipients. It also providesthree different mass messaging service, and you can choose the right type of servicebased on actual use of the network conditions and business requirements.So it is highlypractical. In order to improve the performance and availability of the system, we need toorganize all the servers together to form a cluster system, which can provideuninterrupted service and expand the amount of concurrent systems.This paper aims to design and implement a message pushing cluster system basedon MQTT protocol. This paper describes the significance of the research topic, researchstatus at home and abroad and the subject of the project background. Then introducesthe MQTT protocol and server clustering technology.After an analysis of the businessprocesses and the actual needs of the system, it completes the system design. The wholesystem is divided into the business processes, user authentication, ACL permissionschecking, automatic subscriptions, subject to statistics, server status monitoring, Bridgemode, the load distribution, and several other modules. Then it realizes these modulesbased on the open source projects such as Mosquitto and Redis. System developmentusing Linux and the developing language is C. Compared to single-point system, thesystem has better performance and higher concurrency.