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The question setting here is little bit misleading, because actually these protocols cannot at all be compared together. They are like TCP and IP, layers above each other. [1] Websockets is a low level protocol to provide things that its 'competitor' RESTful http that is on same level does not provide: an always open channel without need for open and close ...


10

They're comparable in that both allow you to have full-duplex communication such that the server can immediately pass data to the client, without the client polling for it (as might be with HTTP). However, Websockets is designed for a simple point-to-point connection between a client and a server. MQTT layers extra abstractions on top of basic message ...


6

What does it actually monitor? From the company's web site: Lively pillbox activity sensors monitor daily medication activity and create an alert whenever anything is missed They also have a web based dashboard, which relatives or carers can check. Lively's safety watch features a pedometer to keep track of steps throughout the day. ...


5

There is the Sonoff Pow WiFi Switch With Power Consumption Measurement or the SONOFF S31 - COMPACT DESIGN SMART PLUG WITH ENERGY MONITORING that seems to be popular with the DIY community. You can reflash that with new firmware (might not be absolutely needed) and receive mqtt messages on your server. You can then have a TICK Stack to receive and store and ...


4

I've done something similar with my pool. I have a Temp/Ph/ORP sensor package that sits by the pool with its sensors in the water. I send the data over WiFi and MQTT to a Node.JS/Express program running on my Docker server. From my desk, I connect to the web interface of the Node.JS/Express program to see what my pool is doing. If the Ph or ORP get to a ...


4

Re the previous answer: the DS18B20 is a digital sensor - it takes the reading locally, stores it locally and though a separate read process digitally transmits the result (usually 12bit resolution) on the OneWire bus to which it is attached. The transmission of the reading to the host is not voltage sensitive (in that a different voltage will represent a ...


4

Keep in mind that the value returned from the DS18B20 is depending on the voltage received. If this voltage has fluctuations, then your readings are going to flux as well. I've seen mine go from 20C to -127C in seconds...found out one of my wires was starting to short. Replaced the wire, problem went away. I would hazard a guess that maybe something along ...


4

If you already have a digital meter inline (or can fit a cheap 2nd hand one), then you can optically monitor the 1000 impulse/kwH LED which is likely present (without needing to interface to the optical serial port present on the meter). You can then integrate the impulses to approximate instantaneous power. Bear in mind that you'll need to infer the ...


4

It probably won't come as a surprise to you, but it doesn't seem like there are any pre-existing solutions which can link your devices together. However, since you said you were interested in custom-built solutions, you might be able to get close to what you want. I did a bit of research into your devices to see if they had open APIs you could take ...


4

Firstly, a simple way to monitor these types of conditions is to monitor how long ago the last task was complete. Instead of knowing when the next script is supposed to be completed, if we know if should be executed every 6 hours, we now just need to compare the last execution time with 'now', if the number of hours between the two (now - lastExecution) is ...


3

I can only speak to AWS' IoT platform. It is certainly reliable and provides a lot of functionality. However there is a significant learning curve, especially if the user has never worked with AWS before. Based on the criteria in your post, I would recommend you also have a look at Grafana. It is a great monitoring tool that is easy to learn, can be self-...


2

You have edited the wrong settings.js file. The version in the node_modules/node-red directory is the template that gets copied to the User directory when Node-RED is started for the very first time. When Node-RED starts it logs the settings file it is using as follows: 21 Jul 13:31:49 - [warn] ------------------------------------------------------ 21 Jul ...


1

Brief your question little bit, if you want to measure water flow you need to learn working principle of solenoid valve and sensor unit if you are measuring water level or something, then you have to learn protocol unit, which protocol you are going to use there, for example if water flow is there you gonna get message in the sense you need to learn some GSM ...


1

I need to have more detail from your question. But, I think you can easily use an Arduino or Mbed to monitor the water meters and communicate back to a server on your LAN. If the sensors will have external power (no battery), then you can connect to a wi-fi network with this type of board. If you have batteries only, then choose a low-power network like Lora....


1

This is typically called a rule-engine where you define rules, and actions to be taken when a rule is met/breached. And this is a common requirement and not specific to IoT. There is no specific technology for rules I know of. But rule engines are provided by platform vendors. For e.g, if you use Azure's IoT services or AWS IoT core, they have rule engines ...


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