Port 1883 (MQTT)
Lightweight publish/subscribe messaging for IoT (TLS on 8883).
- Transport
- TCP
- Internet exposure
- Never expose
Should not be reachable from the internet.
Security notes
- Brokers without authentication expose and accept sensor and control messages from anyone.
- Use TLS and per-client credentials.
When it shows up in your logs
Connections from unknown clients to an MQTT broker should be checked.
Related ports
- 8883
- 502