# MQTT Transmission - Topic Structure - AWS IOT Policy **URL:** \ **Category:** Ignition\ **Created:** [May 25, 2021, 7:44pm UTC](https://forum.inductiveautomation.com/t/mqtt-transmission-topic-structure-aws-iot-policy/47105 "2021-05-25T19:44:59Z")\ **Posts on this page:** 1\ **Showing post:** 6
**Author:** ![LandrethEdward](https://avatars.discourse-cdn.com/v4/letter/l/7bcc69/32.png) [@LandrethEdward](https://forum.inductiveautomation.com/u/LandrethEdward)\ **Post date:** [November 15, 2021, 5:54pm UTC](https://forum.inductiveautomation.com/t/mqtt-transmission-topic-structure-aws-iot-policy/47105/6 "2021-11-15T17:54:55Z")
Hello. From what I can understand here is that there's no way for us to set up a topic with syntax that differs from the sparkplug one as displayed by kcollins1 is that correct? I posted in another thread (link below) asking about how to do a script version of publishing messages that would let us define the topic, but this thread seems more applicable to the out of the box setup of transmission. We have some devices that have predefined subscription syntax so in order to publish out to them we would need to be able to set the topic to do something like build it's topic from the tag filepath. Is there some setting in the transmitter setup that lets us do this instead of defaulting to include spBv1.0 etc? > [@Using MQTT Transmitter to Publish Tag Value](https://forum.inductiveautomation.com/t/using-mqtt-transmitter-to-publish-tag-value/39193/6): > > I think you would want the engine module and this scripting function: [https://docs.chariot.io/display/CLD79/Gateway+Script+MQTT+Publishing](https://docs.chariot.io/display/CLD79/Gateway+Script+MQTT+Publishing) --- _[View the full topic](https://forum.inductiveautomation.com/t/mqtt-transmission-topic-structure-aws-iot-policy/47105)._