Overview

The OASIS standard for MQTT, a lightweight publish/subscribe messaging protocol designed for constrained devices and low-bandwidth networks. v3.1.1 (2014) is the most widely deployed version. v5.0 (2019) adds shared subscriptions, topic aliases, user properties, reason codes, and session/message expiry.

Why it matters for RFID

The dominant messaging protocol for RFID/IoT event streaming. RFID readers from Impinj and Zebra publish tag read events over MQTT to brokers like Mosquitto, HiveMQ, and AWS IoT Core.

Official document

https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.html