January 2026

2026-01-19

- Breaking Change: MQTT V2 Client ID Authentication Requirement (Effective 26.01.2026 14:00 UTC)

Starting January 26th, we will enforce authentication for MQTT connections based on the Client ID.

Required Client ID Format: The Client ID must adhere to the following structure:

<project-id>-<instance>-<random string>

Example:

If you are subscribing to the topic: $share/d13c5fe3-423d-44ac-bbac-f5e1f110b0a0/sandbox/level13/d13c5fe3-423d-44ac-bbac-f5e1f110b0a0

You must use a Client ID such as: d13c5fe3-423d-44ac-bbac-f5e1f110b0a0-sandbox-s12123

mosquitto_sub Example:

mosquitto_sub --host mqtt-v2.high-mobility.com --port 8883 --qos 1
--topic '$share/d13c5fe3-423d-44ac-bbac-f5e1f110b0a0/sandbox/level13/d13c5fe3-423d-44ac-bbac-f5e1f110b0a0'
--id d13c5fe3-423d-44ac-bbac-f5e1f110b0a0-sandbox-xwdsad --disable-clean-session
--cert client_crt.pem --key client_key.pem --cafile ca_crt.pem --verbose --debug 

Need Assistance?

If you are unsure of the correct format, please visit our console. The new required snippet is available in the MQTT V2 sections.