Global – October 29, 2026 -- Historians that stamp MQTT messages with broker arrival time can display an old pressure reading as a new process condition, distorting aggregates, alarms and event order during outage replays.

Plain MQTT defines no process-time field

MQTT specifies only the transport of an application message. It prescribes no timestamp field, industrial clock model or time semantics. The publisher's application contract decides whether a payload carries a time, in what format and with what quality.