MQTT学习了解------阿冬专栏 MQTT V3.1 Protocol Specification 1. Introduction 2. Message format 3. Command messages 4. Flows Appendix A - Topic wildcards
源文档：http://public.dhe.ibm.com/software/dw/webservices/ws-mqtt/mqtt-v3r1.htmlMQTT V3.1 Protocol SpecificationAuthors:International Business Machines Corporation (IBM)EurotechAbstract
