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Questions tagged [mqtt]

For questions concerning the MQTT messaging protocol, a lightweight TCP/IP-based system for machine-to-machine communication.

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0answers
23 views

Not getting LWT MQTT Arduino

I'm trying to test a two combined examples: OTA and MQTT . My goal it to check a LastWill when disconnecting an ESP8266 devic. Surprisingly, a LWT is not sent to designated topic. code has not ...
2
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2answers
30 views

MQTT - keepAlive using Arduino

I'm using MQTT broker for my IOT devicess, mostly ESP8266 ( some are NodeMCU, some Wemos mini, and some are Sonoff) , running an Arduino code, some time ( about a year ). MQTT broker is running on a ...
3
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0answers
32 views

Using RPC in IoT environments

I would like to use RPC for communication between fog nodes. As the connection between the nodes is wireless (802.15.4), I don't want to use an RPC framework that uses HTTP (like gRPC). I know that ...
2
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1answer
52 views

Difference between edge server and mqtt broker

As I am new to the IoT world, I would like to ask for a clarification. I was reading somewhere about the general idea of having devices communicating with each other or storing information in a ...
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0answers
28 views

ESP8266 and MQTT not working with new router [closed]

Got a new router from the ISP and my ESP8266 NodeMCUs are causing problems, they need very long to connect to WiFi (3-4 mins), which wouldn't be that big of a problem, but they also don't connect to ...
3
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2answers
70 views

Is MQTT-SN still “new” or is it obsolete?

I have an existing IoT project based on MQTT and am looking at extending the application to include battery powered end nodes using Zigbee mesh. It logically seems the most appropriate way to do this ...
2
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1answer
53 views

Why one should choose GraphQL instead of MQTT for an IOT project?

Just got assigned to the IoT Project. It is regarding a simple IoT cellular device that pretty much acts as a garage door control. The device can be called using the phone and then opens the gate, ...
2
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1answer
23 views

Why does MQTT Broker forget connection from SIM800 module?

I am working on SIM800 module and MQTT broker (Mosquitto) to design a kind of IoT device. When i try the MQTT server, i encountered this problem. The SIM800 connects MQTT server on TCP connection. You ...
3
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1answer
40 views

What is wrong with this MQTT-SN bridge?

I am using this MQTT-SN bridge, with no changes except that I rigged it to give a hex dump of the buffer if it does not contain a valid MQTT-SN packet. I am experiencing a strange problem: sometimes ...
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0answers
46 views

What are lower latency alternatives to using MQTT brokers with the ESP8266

I'm experimenting withThe nodeMCU board Attempting to proto type out an IOT project. My first iteration involved Using an MQTT broker to send messages between my computer and the board. Due to the ...
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3answers
57 views

Cloud mqtt broker

I am completely new to the world of IoT and I want some recommendations. I want to build a home automation system that is accessible from anywhere in the world using internet. The ultimate goal is the ...
2
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0answers
40 views

MQTT implementation recommendation for an IoT device

I have used HTTP/s based REST API for IoT application and it works well but consumes more data bandwidth and power. Also, the server resources consumed are too high for the long polling-based method. ...
2
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0answers
79 views

Looking for MQTT broker and client recommendations

Working to make a network of remote sensors using MQTT I'm looking for an implementation of a broker an a matching client. Requirements broker to be deployed in a cloud server like EC-2 and client ...
2
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1answer
58 views

MQTT vs HTTP Connection - Server to Client

I need to understand the difference between HTTP and MQTT connection. I want to send data from a Server to a Client without using port forwarding. If I understand, using HTTP is not possible; so ...
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0answers
60 views

Is Firebase a valid replacement for MQTT?

I wonder if the realtime techology of Firebase (Either Cloud Firestore or Realtime Database) is a valid workaround for MQTT, for avoiding the broker link. We must bear in mind that the system could be ...
2
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0answers
45 views

Scalability: CoAP vs. MQTT-SN

Which of these protocols is better in scalability? In terms of security, QoS and LLN are only small differences. It would even say, they are very similar to each other. But how is the performance in ...
3
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1answer
39 views

MQTT-SN using any encryption?

Does MQTT-SN provide any encryption like AES-128 etc.? As I know, it's using a simple binary encryption but in my opinion this cannot be seen as a security feature. Many thanks in advance :)
3
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1answer
97 views

How to send continuous data from a few ESP8266 to a webserver?

I am new to ESP8266 boards and IoT programming and I don't know how to describe better what I want to do without a picture. Question: How to send continuous data from 4 esp8266 WiFi clients to a ...
4
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0answers
56 views

Advice for building a home automation system

I am not sure what technologies to use in order to build an IoT system for my home. I have a few sensors and some other devices that need to be controlled (like a doorlock) placed in my house. All ...
0
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1answer
13 views

Eclipse broker publishes off on subscribe

I'm testing an MQTT client setup with the Eclipse test server. I noticed off is sent automatically to every topic my client subscribes to, and the retain flag is set. I can see the logic behind it but ...
4
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1answer
74 views

How to extract values of multiple topics in onMessageArrived(message) function of Paho MQTT JavaScript API?

I have created a Publisher Script using Paho MQTT JavaScript API which publishes values to two topics MyHome/Temp and MyHome/Hum. The script is running successfully and publishing data to CloudMQTT ...
2
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1answer
70 views

Connect to MQTT Server without opening port

I have a MQTT client in an internal network and an MQTT server somewhere in Cloud. How can I connect to MQTT Server without opening port in the Client network?
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0answers
154 views

MQTT subscribing is not working

I am working to connect my server to the clients via an MQTT broker. The mqtt client gets connected. But after publishing a message, the subscribe code receives a connection acknowledgment. The ...
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0answers
110 views

Why is Mosquitto broker and Paho client running CPU 100% on connection?

I would like to use the mosquitto MQTT broker using Websockets. I am running mosquitto version 1.6.2 on a Debian 8 server. "normal" MQTT works fine, but I am having a problem trying to connect using ...
2
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1answer
129 views

What's the size in bytes of a single, TLS-encrypted MQTT message?

To determine the use of bandwidth usage, I need to know the exact size of a MQTT message sent from a device to a server. This message looks something like this: client.publish(topic="foo", payload="...
3
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1answer
89 views

How can I use Raspberry Pi to communicate with my Z-Wave gateway?

I am quite new to Z-Wave. I have a gateway, 2 z-wave sockets and 3 light switches. Everything comes from Keemple brand if that helps. However, using Keemple I cannot automate things the way I would ...
2
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0answers
68 views

Create Light Switch with HAP-NodeJS, MQTT and fail safe

I'm trying to get into setting up my own home automation. I've already setup HAP-NodeJS & MQTT on a raspberry and I've flashed a esp01 with NodeMCU. What I want to do is create a light switch ...
0
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1answer
67 views

MQTT Client behind router and Port forwarding for subscription of Client [closed]

I use MQTT (Mosquitto) and several ESP8266 for sensoring issues. I want that the clients also can "subsribe" to trigger actions on the clients. The MQTT Server is placed in a VLAN of my main router. ...
1
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1answer
330 views

How to send data to ThingsBoard using MQTT in python?

I want to send data to ThingsBoard and display it in widget On dashboard. By Following this tutorial I have: Created Device on ThingsBoard by logging into Tenant Administrator. Device Description: ...
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0answers
24 views

is it possible to add devices via Android app by a user using google AUTH API in Google Iot core

I am trying to make an app in which the user can login via google and then add devices (multiple but will have same telemetry data fields) so that user can click (/touch) on each field and view the ...
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0answers
96 views

Digital Gauge Widget not showing live reading of device in thingsboard Dashboard

I am following getting started guide of ThingsBoard. In their getting started tutorial, I was instructed to run demo-tool.js file from here. It will send the random value of humidity and temperature. ...
1
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0answers
155 views

use Gsm Sim800L To Publish data using MQtt [closed]

I have a Module Gsm Sim800L and I must Publish Data to a nodeRed Server Of IBM Bluemix. I used the library (Arduino MQTT Library for SIM800 GSM Modem) at this Link : https://elementztechblog....
3
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1answer
58 views

IoT <-> Cloud communication method

I am struggling with creation of multiple IoT devices (NanoPi like) which will be controlled via cloud server. I wish to use MQTT as I see this is the best method for small footprint. I know MQTT has ...
3
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2answers
76 views

connect a device automatically without configuring at iot platform end

My main goal is to connect devices but only with an access token and not by manually adding devices to the cloud IoT platform Is there a platform to do that automatically? How to do it/Which platform ...
2
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1answer
62 views

Cannot connect SensorTag cc2650 to IBM watson IoT platform using their android app

I have SensorTag cc2650 from Texas Instruments with their android app installed in my Phone. I am getting an exception while connecting IBM Watson IoT. It worked fine with quick-start service but ...
7
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4answers
454 views

Which IoT platform to visualize real-time and historical sensor data?

In order to prepare some tutorials for my students, I am working on a few DIY electronics projects in the field of IoT. I want to use ESP32, ESP8266, Arduino Uno, and Raspberry Pi. I am more deep on ...
3
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1answer
135 views

The Things Network AWS IoT integration

I have followed the tutorial for the AWS integration but cannot get the MQTT messages to display in the AWS IoT Core. I assume bridging is not working since I can get the messages in an external ...
2
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1answer
716 views

Communicate with MQTT over LoRa

I have two Raspberry Pis with a LoRa module each (Microchip RN2483, connected over serial). How do I tell MQTT (in Python) to use the LoRa motes (/dev/ttyAMC0) instead of Ethernet or Wi-Fi?
2
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1answer
577 views

Are MQTT Brokers able to retain/cache some data for a certain amount of time and then send to the subscribers?

I currently have a Mosquitto MQTT Broker on which some IoT Nodes publish their information on a specific topic. I have an instance of Telegraf from InfluxData running that subscribes to this topic and ...
2
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2answers
266 views

Custom sensor readings with Amazon Alexa

TLDR: I want to query Alexa for the current humidity sensor reading by asking: "What is the current humidity, Alexa?" The answer should be similar to: "The current humidity level is 56.7%" ...
6
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3answers
596 views

Which free dashboards are also MQTT brokers?

I'm trying to find a dashboard which: Has pretty widgets for data display Can subscribe to, and display MQTT data that I publish Can publish commands to subscribers (eg: "Driveway light switch: turn ...
3
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1answer
450 views

mosquitto_pub succeeds but ThingsBoard device telemetry not updated

I'm using ThingsBoard demo, with a throw-away test device: Name: Test Device ID: 779e65d0-366f-11e9-b411-fdd6fdf5c064 Access Token: DdqzgX0Q4QLBbveiuY8e I set up a subscriber: mosquitto_sub -h demo....
3
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1answer
98 views

Connect MQTT to cloud

I installed mosquitto 1.5.7 on Windows 7 and made it subscribe and publish successfully on a local host but mosquitto failed to make connection to ubidot the publish mosquitto_pub -h "things.api....
6
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4answers
760 views

Alternatives to MQTT for local / remote bridging

Amongst the plethora of MQTT questions, I am wondering what are some alternatives to MQTT for when all messages sent to a topic need to be kept, and in a queue for a new subscriber. At my company, we ...
3
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1answer
88 views

Quick questions about MQTT of a beginner

I'm new to MQTT so I'll try to explain my situation first and then ask some questions about MQTT. Basically what I'm trying to do is set up some sensors in two houses, A and B, and be able to manage ...
2
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1answer
195 views

How does the MQTT server output a single raw file from multiple client publications?

I'm trying my first IoT project whereby I want to: have an electret microphone capture audio have an ESP8266 NodeMCU 12-E board submit captured audio to a remote server have a remote server receive ...
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1answer
37 views

Does mqtt have late delivery feature if no client is subscribed?

Can Mqtt broker forward messages which have not been sent to any client ?
1
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0answers
125 views

How does Homeassistant MQTT publish via POST [duplicate]

I am currently using Home Assistant MQTT publish service from this the link below Link: https://developers.home-assistant.io/docs/en/external_api_rest.html The URL is: https:///api/services/mqtt/...
4
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0answers
267 views

Node red MQTT node cannot connect to Azure IoT Hub

I am aware that there is Azure IoT Hub palette in Node-red, which is specifically designed to interact with Azure IoT Hub. I tried that and it worked fine most of the time. However, due to an ...
0
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1answer
273 views

POST messages in JSON to mosquitto MQTT not being received from node-RED mqtt node

Not sure how much better I can phrase it in the question but i'll try to explain to the best I can. What I am trying to do: Using IFTTT Webhook to POST a JSON message in MQTT Format. POST URL: ...