这是一个iOS平台上的MQTT客户端，仅作测试之用。
该客户端实现了MQTT协议的基本功能，可以完成主题订阅，消息的发布、接收与存储。主要使用了开源的MQTTKit库,该库也是对开源MQTT代理mosquitto中的库代码用Objective-C语言进行了封装。
MQTT协议简单，轻量，后续可拓展用于推送、IM即时聊天、远程控制等领域。
关于MQTT，以下是百度百科的描述：
MQTT（Message Queuing Telemetry Transport，消息队列遥测传输）是IBM开发的一个即时通讯协议，有可能成为物联网的重要组成部分。该协议支持所有平台，几乎可以把所有联网物品和外部连接起来，被用来当做传感器和致动器（比如通过Twitter让房屋联网）的通信协议。
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