Authorization

Authorization refers to controlling the permissions for MQTT client's publish and subscribe operations. The basic principle of EMQX's authorization mechanism is that when a client attempts to publish or subscribe, EMQX retrieves the client's permission data from the data source according to a specific process or user-defined query statements. It then matches the permissions with the operation to be performed, allowing or denying the operation based on the match results.

A single piece of client permission data consists of the following parts:

Permission	Client	Action	Action Details
Allow/Deny	Client ID/Username/IP Address	Publish/Subscribe/Publish Subscribe	Topic/QoS/Retained Messages

Default Authorization

EMQX Platform provides a default authentication method, which will authorize based on rules stored in the built-in database.

Extended Authorization

In addition to the default authorization based on the built-in database, it also supports authorization authentication through integration with various backend databases, including MySQL, PostgreSQL, Redis, and HTTP.

• Authorize with HTTP
• Authorize with MySQL
• Authorize with PostgreSQL
• Authorize with Redis

Authorization Support by Version

Version	Default Authorization	Extended Authorization
Serverless	✓	✗
Dedicated	✓	✓
BYOC	✓	✓