Port 1883: MQTT
Port 1883 is MQTT, a lightweight publish-subscribe messaging protocol built for IoT devices with limited bandwidth or power. A device publishes to a topic and a broker fans the message out to every subscriber, without sender and receiver needing to connect directly.
| Port number | 1883 |
|---|---|
| Service | MQTT publish-subscribe messaging |
| Protocol | TCP |
| Category | IoT & automation |
| Default encryption | No |
Frequently asked questions
What is port 1883 used for?
Port 1883 is MQTT, a lightweight publish-subscribe messaging protocol built for IoT devices with limited bandwidth or power. A device publishes to a topic and a broker fans the message out to every subscriber, without sender and receiver needing to connect directly.
Is port 1883 TCP or UDP?
Port 1883 (MQTT) uses TCP.
Is port 1883 secure?
Port 1883 is not encrypted by default. Where possible, use an encrypted alternative or tunnel it over TLS or a VPN.
Should I open port 1883 on my firewall?
Only if you specifically need MQTT. Expose it to the smallest set of trusted sources, and never open database or Windows-service ports to the whole internet.