# Application Development **URL:** https://www.thethingsnetwork.org/forum/c/application-development/15.md [Latest](https://www.thethingsnetwork.org/forum/latest.md) · [Categories](https://www.thethingsnetwork.org/forum/categories.md) · [Tags](https://www.thethingsnetwork.org/forum/tags.md) --- ## [About the Application Development category](https://www.thethingsnetwork.org/forum/t/about-the-application-development-category/29)
**Author:** [@johan](https://www.thethingsnetwork.org/forum/u/johan)\ **Replies:** 0
Everything related to application development. Top-level category for everything related to application development. --- ## [Unable to connect to MQTT server from Node-Red](https://www.thethingsnetwork.org/forum/t/unable-to-connect-to-mqtt-server-from-node-red/69301)
**Author:** [@1tim](https://www.thethingsnetwork.org/forum/u/1tim)\ **Replies:** 17\ **Last updated:** [October 22, 2026, 2:18pm UTC](https://www.thethingsnetwork.org/forum/t/unable-to-connect-to-mqtt-server-from-node-red/69301 "2026-10-22T14:18:20Z")
Hi, I am now stumped with what I thought would be a simple cog to implement in a bigger solution. I am unable to connect to my TTN application using MQTT. I first ran Node-Red within a docker container on a Pi5, which… --- ## [TTN support for MQTT SparkPlug?](https://www.thethingsnetwork.org/forum/t/ttn-support-for-mqtt-sparkplug/73269)
**Author:** [@kayakpete](https://www.thethingsnetwork.org/forum/u/kayakpete)\ **Replies:** 3\ **Last updated:** [February 26, 2026, 6:52pm UTC](https://www.thethingsnetwork.org/forum/t/ttn-support-for-mqtt-sparkplug/73269 "2026-02-26T18:52:03Z")
Good morning, TTN friends - I have some temperature sensors out in the field that utilize our Holland Michigan LORA city-wide network. The nodes report up through gateways to TTN, and I pull data down via MQTT. All is… --- ## [HowTo send downlinks with empty frm\_payload](https://www.thethingsnetwork.org/forum/t/howto-send-downlinks-with-empty-frm-payload/72816)
**Author:** [@ullriti](https://www.thethingsnetwork.org/forum/u/ullriti)\ **Replies:** 0\ **Last updated:** [December 10, 2025, 8:43pm UTC](https://www.thethingsnetwork.org/forum/t/howto-send-downlinks-with-empty-frm-payload/72816 "2025-12-10T20:43:54Z")
Summary Hi all, to read configuration from my TTN devices, I need to send an empty downlink (e.g., on port 7). However, The Things Stack rejects this with a “no\_payload” error when using the API. Iam using a self-host… --- ## [Node-red MQTT](https://www.thethingsnetwork.org/forum/t/node-red-mqtt/72799)
**Author:** [@lora\_Obs-Banyuls](https://www.thethingsnetwork.org/forum/u/lora_Obs-Banyuls)\ **Replies:** 2\ **Last updated:** [December 10, 2025, 11:22am UTC](https://www.thethingsnetwork.org/forum/t/node-red-mqtt/72799 "2025-12-10T11:22:05Z")
Hello, I’m using the TTN MQTT application. I’ve already connected to two applications, but I’m currently unable to connect a third using the Node-RED MQTT-in node. The console displays “failed to connect.” I’m using port… --- ## [TTN Node data visible & usable in Domoticz](https://www.thethingsnetwork.org/forum/t/ttn-node-data-visible-usable-in-domoticz/12384)
**Author:** [@Ooievaar](https://www.thethingsnetwork.org/forum/u/Ooievaar)\ **Replies:** 10\ **Last updated:** [November 27, 2025, 10:12pm UTC](https://www.thethingsnetwork.org/forum/t/ttn-node-data-visible-usable-in-domoticz/12384 "2025-11-27T22:12:28Z")
Hi, I am looking for a solution that makes it possible to use the data from my nodes in Domoticz, a home automation system. This solution should run on a Raspberry Pi (on which Domoticz is also running). That was the e… --- ## [Applications API call returns nothing](https://www.thethingsnetwork.org/forum/t/applications-api-call-returns-nothing/68963)
**Author:** [@Solvera\_Lynx\_TheThin](https://www.thethingsnetwork.org/forum/u/Solvera_Lynx_TheThin)\ **Replies:** 17\ **Last updated:** [November 9, 2025, 12:17pm UTC](https://www.thethingsnetwork.org/forum/t/applications-api-call-returns-nothing/68963 "2025-11-09T12:17:02Z")
Hello, it has come to our attention that we are unable to retrieve a list of applications from following API call: GET https://eu1.cloud.thethings.network/api/v3/applications Is there any reason for that? I admit, tha… --- ## [How do commercial LoRaWAN products handle device provisioning and access?](https://www.thethingsnetwork.org/forum/t/how-do-commercial-lorawan-products-handle-device-provisioning-and-access/72503)
**Author:** [@artichoke](https://www.thethingsnetwork.org/forum/u/artichoke)\ **Replies:** 8\ **Last updated:** [November 3, 2025, 1:29pm UTC](https://www.thethingsnetwork.org/forum/t/how-do-commercial-lorawan-products-handle-device-provisioning-and-access/72503 "2025-11-03T13:29:33Z")
Hi, I’m developing a small-scale LoRaWAN/IoT system and i am trying to understand how device provisioning, ownership transfer, dashboard access, etc. is done in commercial products. From what I see, a lot of vendors (D… --- ## [How to login to TTN MQTT server](https://www.thethingsnetwork.org/forum/t/how-to-login-to-ttn-mqtt-server/72373)
**Author:** [@jpt](https://www.thethingsnetwork.org/forum/u/jpt)\ **Replies:** 7\ **Last updated:** [October 15, 2025, 1:28pm UTC](https://www.thethingsnetwork.org/forum/t/how-to-login-to-ttn-mqtt-server/72373 "2025-10-15T13:28:51Z")
Hi, I am new to LoRa and TTN. I would like to attach https://lorabridge2.github.io/ to TTN instead of owning a dedicated gateway. I advised the AI to implement the connector and it looks fine now. But: Login to the M… --- ## [MQTT broker behavior on TTN / The Things Stack](https://www.thethingsnetwork.org/forum/t/mqtt-broker-behavior-on-ttn-the-things-stack/72277)
**Author:** [@iyan-zapatero](https://www.thethingsnetwork.org/forum/u/iyan-zapatero)\ **Replies:** 3\ **Last updated:** [September 30, 2025, 11:09am UTC](https://www.thethingsnetwork.org/forum/t/mqtt-broker-behavior-on-ttn-the-things-stack/72277 "2025-09-30T11:09:37Z")
I am working with ThingsBoard (version 4.0.1) and integrating it with TTN (The Things Stack) via MQTT. However, we are facing a recurring issue where duplicate messages arrive in our ThingsBoard integrators. Because the … --- ## [Cannot connect to MQTT](https://www.thethingsnetwork.org/forum/t/cannot-connect-to-mqtt/72124)
**Author:** [@gpezzella](https://www.thethingsnetwork.org/forum/u/gpezzella)\ **Replies:** 2\ **Last updated:** [August 29, 2025, 6:49pm UTC](https://www.thethingsnetwork.org/forum/t/cannot-connect-to-mqtt/72124 "2025-08-29T18:49:22Z")
Hi I have already been connected yesterday with MQTT using MQTT Explorer but now don’t work anymore: Why? I’m in Italy and use the european Server Thanks --- ## [How to control the JSON formatter with the API and send it to the application server in hexadecimal using MQTT communication](https://www.thethingsnetwork.org/forum/t/how-to-control-the-json-formatter-with-the-api-and-send-it-to-the-application-server-in-hexadecimal-using-mqtt-communication/72100)
**Author:** [@naraoka](https://www.thethingsnetwork.org/forum/u/naraoka)\ **Replies:** 3\ **Last updated:** [August 28, 2025, 9:23am UTC](https://www.thethingsnetwork.org/forum/t/how-to-control-the-json-formatter-with-the-api-and-send-it-to-the-application-server-in-hexadecimal-using-mqtt-communication/72100 "2025-08-28T09:23:33Z")
I’m currently investigating whether this is possible using TTN. I’m looking into the following two points: Is it possible to send data to an application server in hexadecimal format using MQTT communication from TTN … --- ## [Working MQTT Bridge configuration for Homeassistant](https://www.thethingsnetwork.org/forum/t/working-mqtt-bridge-configuration-for-homeassistant/65754)
**Author:** [@mikamuh](https://www.thethingsnetwork.org/forum/u/mikamuh)\ **Replies:** 4\ **Last updated:** [July 17, 2025, 9:55am UTC](https://www.thethingsnetwork.org/forum/t/working-mqtt-bridge-configuration-for-homeassistant/65754 "2025-07-17T09:55:36Z")
Hi Everyone, I am desperately trying to get my Homeassistant MQTT Broker to establish a bridge to my application using an encrypted communication. My configuration page in the MQTT Add on is set as follows: Certificat… --- ## [Different HTTP Post endpoint based on fport](https://www.thethingsnetwork.org/forum/t/different-http-post-endpoint-based-on-fport/38207)
**Author:** [@koovea](https://www.thethingsnetwork.org/forum/u/koovea)\ **Replies:** 10\ **Last updated:** [May 21, 2025, 2:57pm UTC](https://www.thethingsnetwork.org/forum/t/different-http-post-endpoint-based-on-fport/38207 "2025-05-21T14:57:46Z")
Hello, I am developing a temperature sensor application. My end device send 3 frame types and I use one port for each. I can prepare differently JSON payload format based on fport. Now I am wondering if I can redirec… --- ## [Unknown certificate authority using webhooks integration](https://www.thethingsnetwork.org/forum/t/unknown-certificate-authority-using-webhooks-integration/58219)
**Author:** [@lyanchev](https://www.thethingsnetwork.org/forum/u/lyanchev)\ **Replies:** 4\ **Last updated:** [April 22, 2025, 7:23am UTC](https://www.thethingsnetwork.org/forum/t/unknown-certificate-authority-using-webhooks-integration/58219 "2025-04-22T07:23:09Z")
Hello everyone! We have an integration with TTN and we are using webhooks. We never had any issues until now, when we need to change our certificate. We are not using the CLI and we are seeing some errors in the Console… --- ## [Multiple clients connection to mqtt server](https://www.thethingsnetwork.org/forum/t/multiple-clients-connection-to-mqtt-server/71164)
**Author:** [@hansju22](https://www.thethingsnetwork.org/forum/u/hansju22)\ **Replies:** 1\ **Last updated:** [April 16, 2025, 12:37pm UTC](https://www.thethingsnetwork.org/forum/t/multiple-clients-connection-to-mqtt-server/71164 "2025-04-16T12:37:57Z")
I have one application in ttn and 3 mqtt clients at the same time, which will connect to this server. All use the same credentional. ( I set it up under mqtt integration). The first client works well. If the second and … --- ## [Tekelek TEK766 payload format](https://www.thethingsnetwork.org/forum/t/tekelek-tek766-payload-format/37444)
**Author:** [@cloudnet](https://www.thethingsnetwork.org/forum/u/cloudnet)\ **Replies:** 21\ **Last updated:** [April 5, 2025, 6:02pm UTC](https://www.thethingsnetwork.org/forum/t/tekelek-tek766-payload-format/37444 "2025-04-05T18:02:48Z")
Hello. I have recieved a tekelek766 lorawan device. Registered it and it is talking to the TTN. However I have asked the company for the payload and they have not provided me the documentation to interpret the data. … --- ## [JSON import of devices errors](https://www.thethingsnetwork.org/forum/t/json-import-of-devices-errors/70800)
**Author:** [@LMSystems](https://www.thethingsnetwork.org/forum/u/LMSystems)\ **Replies:** 2\ **Last updated:** [March 14, 2025, 1:55pm UTC](https://www.thethingsnetwork.org/forum/t/json-import-of-devices-errors/70800 "2025-03-14T13:55:51Z")
Hi guy´s We earlier used a EUI/onboarding program to produce import .json files for our devices like below {“ids”:{“device\_id”:“a84041d4d18332e6”,“dev\_eui”:“A84041D4D18332E6”,“join\_eui”:“5a656e7a725a3635”},“name”:“LST2… --- ## [Azure IoT Hub - LoRaWAN Class Capabilities](https://www.thethingsnetwork.org/forum/t/azure-iot-hub-lorawan-class-capabilities/70752)
**Author:** [@obarker94](https://www.thethingsnetwork.org/forum/u/obarker94)\ **Replies:** 4\ **Last updated:** [March 3, 2025, 12:33pm UTC](https://www.thethingsnetwork.org/forum/t/azure-iot-hub-lorawan-class-capabilities/70752 "2025-03-03T12:33:01Z")
Hi all, I’ve got an integration setup between TTN and Azure IoT Hub. I am currently using the Azure IoT Hub as my primary device registry. Following the documentation, I am updating device twins with their required LoR… --- ## [Can't delete application](https://www.thethingsnetwork.org/forum/t/cant-delete-application/70708)
**Author:** [@earvdl](https://www.thethingsnetwork.org/forum/u/earvdl)\ **Replies:** 0\ **Last updated:** [February 26, 2025, 11:25pm UTC](https://www.thethingsnetwork.org/forum/t/cant-delete-application/70708 "2025-02-26T23:25:04Z")
Please ignore message below. I made a mistake. I created an application with name test-application-earvdl rather than test-application-earvdl@ttn. I can delete the application, but have first to remove the devices in it. … --- ## [How to experiment with LoRa PHY layer parameters?](https://www.thethingsnetwork.org/forum/t/how-to-experiment-with-lora-phy-layer-parameters/62472)
**Author:** [@raghav1197](https://www.thethingsnetwork.org/forum/u/raghav1197)\ **Replies:** 14\ **Last updated:** [February 20, 2025, 10:44am UTC](https://www.thethingsnetwork.org/forum/t/how-to-experiment-with-lora-phy-layer-parameters/62472 "2025-02-20T10:44:18Z")
Hey everyone, I am trying to test the effects of physical layer parameters on its packet reception performance. I am using The Things Uno board as end node and The Things Indoor Gateway. I want a general right direction… --- ## [TrackerD no measurements appear at ttnmapper?](https://www.thethingsnetwork.org/forum/t/trackerd-no-measurements-appear-at-ttnmapper/70435)
**Author:** [@huegelfunk](https://www.thethingsnetwork.org/forum/u/huegelfunk)\ **Replies:** 5\ **Last updated:** [February 14, 2025, 12:34pm UTC](https://www.thethingsnetwork.org/forum/t/trackerd-no-measurements-appear-at-ttnmapper/70435 "2025-02-14T12:34:42Z")
Hi, I’m a TTN freshman but managed to get my TrackerD GPS tracker up and pushing messages to TTN. Unfortunatly I don’t seem to push measurements to the ttnmapper, even if I doublechecked my setup twice: Device transmit… --- ## [New open source web app to manage TTN devices](https://www.thethingsnetwork.org/forum/t/new-open-source-web-app-to-manage-ttn-devices/69848)
**Author:** [@mabc](https://www.thethingsnetwork.org/forum/u/mabc)\ **Replies:** 2\ **Last updated:** [November 24, 2024, 11:44am UTC](https://www.thethingsnetwork.org/forum/t/new-open-source-web-app-to-manage-ttn-devices/69848 "2024-11-24T11:44:30Z")
Hi, I have developed a web app to manage sensors, actuators, cameras, and GPS. It works with TTN. It’s simple and easy to use —less powerful than others solutions like Home Assistant but maybe a better fit for someone p… --- ## [TTN Usage Stats: Device and Gateway Activity Tracker](https://www.thethingsnetwork.org/forum/t/ttn-usage-stats-device-and-gateway-activity-tracker/70133)
**Author:** [@mateo\_08](https://www.thethingsnetwork.org/forum/u/mateo_08)\ **Replies:** 2\ **Last updated:** [December 24, 2024, 10:13pm UTC](https://www.thethingsnetwork.org/forum/t/ttn-usage-stats-device-and-gateway-activity-tracker/70133 "2024-12-24T22:13:04Z")
My gateway has been running for a month now, actively contributing to the TTN network in my area! Curious about its usage, I developed an application to track the devices connecting to it. The video showcases the featur… --- ## [MClimate Vicki thermostat decoder](https://www.thethingsnetwork.org/forum/t/mclimate-vicki-thermostat-decoder/44405)
**Author:** [@cnoork](https://www.thethingsnetwork.org/forum/u/cnoork)\ **Replies:** 6\ **Last updated:** [December 24, 2024, 2:58pm UTC](https://www.thethingsnetwork.org/forum/t/mclimate-vicki-thermostat-decoder/44405 "2024-12-24T14:58:11Z")
For who has interest, I have modified the downlink encoder from MClimate and also added all variables in the decoder. In Node Red I have created a controller to control the valve to get the room to the desired temperatu… --- ## [normalizeUplink vs the mandatory schema validation](https://www.thethingsnetwork.org/forum/t/normalizeuplink-vs-the-mandatory-schema-validation/70067)
**Author:** [@colinsurprenant](https://www.thethingsnetwork.org/forum/u/colinsurprenant)\ **Replies:** 10\ **Last updated:** [December 16, 2024, 10:46pm UTC](https://www.thethingsnetwork.org/forum/t/normalizeuplink-vs-the-mandatory-schema-validation/70067 "2024-12-16T22:46:32Z")
Hello, I am trying to understand as to why the validation of the output of the normalizeUplink() function against the Normalized Payload Schema is mandatory? I really like the idea of the decoupling between decodeUplin… --- ## [Different structure for rx\_metadata for gateways from the packet broker](https://www.thethingsnetwork.org/forum/t/different-structure-for-rx-metadata-for-gateways-from-the-packet-broker/69365)
**Author:** [@Archer](https://www.thethingsnetwork.org/forum/u/Archer)\ **Replies:** 11\ **Last updated:** [October 11, 2024, 12:24pm UTC](https://www.thethingsnetwork.org/forum/t/different-structure-for-rx-metadata-for-gateways-from-the-packet-broker/69365 "2024-10-11T12:24:05Z")
Hello, I would like to set up a monitoring view for the gateways. The data from rx\_metadata is part of my considerations. It is clear and understandable that there are differences between the data of gateways from the … --- ## [Unable to get TTN integration with AWS IoT working](https://www.thethingsnetwork.org/forum/t/unable-to-get-ttn-integration-with-aws-iot-working/69349)
**Author:** [@rogacky](https://www.thethingsnetwork.org/forum/u/rogacky)\ **Replies:** 0\ **Last updated:** [October 3, 2024, 8:33am UTC](https://www.thethingsnetwork.org/forum/t/unable-to-get-ttn-integration-with-aws-iot-working/69349 "2024-10-03T08:33:33Z")
I am trying to integrate TTN device connection with AWS according to this tutorial: https://www.thethingsindustries.com/docs/integrations/cloud-integrations/aws-iot/deployment-guide/ I am using sandbox template for eu1 … --- ## [SSO OAuth Keycloak - Unexpected Application Error](https://www.thethingsnetwork.org/forum/t/sso-oauth-keycloak-unexpected-application-error/67577)
**Author:** [@campuski-p](https://www.thethingsnetwork.org/forum/u/campuski-p)\ **Replies:** 1\ **Last updated:** [August 19, 2024, 8:04pm UTC](https://www.thethingsnetwork.org/forum/t/sso-oauth-keycloak-unexpected-application-error/67577 "2024-08-19T20:04:39Z")
Hello everyone, I am currently trying to set up a Single Sing On via the command-line interface; specifically Keycloak. The following link leads to the description for setting up an SSO service for TTN/TTI: Single Sign… --- ## [End device stop showing live data and some parameters are missing in device settings](https://www.thethingsnetwork.org/forum/t/end-device-stop-showing-live-data-and-some-parameters-are-missing-in-device-settings/68637)
**Author:** [@javierriascos](https://www.thethingsnetwork.org/forum/u/javierriascos)\ **Replies:** 0\ **Last updated:** [July 16, 2024, 4:17pm UTC](https://www.thethingsnetwork.org/forum/t/end-device-stop-showing-live-data-and-some-parameters-are-missing-in-device-settings/68637 "2024-07-16T16:17:23Z")
I’m new using lora, and I managed to get the things stack open source running on a server, but I got a problem with end devices, after 3 hours or so, the live data stream stops and some of the device’s parameters are mis… [Next page](https://www.thethingsnetwork.org/forum/c/application-development/15.md?page=1)