I am a beginner at cloud computing, and I'm hoping to get some guidance or advice as to how I can set up a cloud connected to IoT devices and a running application to control the behavior of these devices.
Firstly, there are 5 devices that have to connected via 3G or LTE because of the distance among the devices, so the way I am thinking of is connecting them to the internet using dynamic public ip addresses and using a dynamic DNS server. It seems like I should be using AWS-IoT service to manage these devices. How should I go about doing that, or is there a better approach? The devices all use MQTT and/or REST API.
The next step is to write an application and I was suggested to use AWS Lambda, am I heading towards the correct direction? How do I link the connected devices on AWS-IoT to AWS Lambda?
I know the question may sound vague but I am still new and exploring different solutions. Any guidance or recommendations for the right step forward is appreciated.
I assume your devices (or, one of them) has 64-bit CPU (x86 or Arm) that run Linux.
It's a kind of 70:30 balance where:
- 70% of the work needs to focus on building and testing edge-logic.
- 30% of the work on the rest (IoT Cloud, Lambda etc).
Here is what I suggest.
1/ Code your edge-logic first! (the piece of code that you want to execute ultimately on your devices).
2/ Test it on-the-edge by logging on to the devices (if you can) via SSH and running it.
3/ Once you have that done, 70% of the job is over.
4/ Rest 30% is to complete the jigsaw in cloud. Best place to start: Lambda and Greengrass.
5/ To summarize it all, you will create greengrass components on cloud, install AWS Greengrass Core software on your device, followed by deploying your configuration on your device over-the-air (OTA).
Now, you can use any MQTT client (or) biult-in MQTTTester of AWS IoT -> Test wizard to send a message to your topic to trigger your edge-logic on the device!
Good luck!
cheers,
ram
Related
I was searching in the net about connection between STM32 microcontroller and AWS IoT core, didnt come across any. I cam across articles where the discovery board of STM32 is used to connect to AWS IoT core. But I want a simple way to connect the STM32 microcontroller to AWS IoT core with the help of WiFi module (since STM32 microcontroller boards dont usually have WiFi modules)
I tried searching as I have already told but didnt come any resources related to what I was searching. I was specifically looking for resources related to STM32F1 series.
You need internet connectivity to be able to connect to aws iot. That could be wireless or ethernet. STM32f4 could work with ethernet.
Or, you move to ESP32.
What I’ve done in the past is to connect a stm32L1 to esp8266 over spi.
AWS provides a tutorial on how to use the IoT Device SDK for Embedded C - https://docs.aws.amazon.com/iot/latest/developerguide/iot-embedded-c-sdk.html
They also provide sample apps specifically ported for STM32 (STM32L4 discovery board - https://www.st.com/en/evaluation-tools/b-l475e-iot01a.html) based on WiFi connectivity.
That can be a good starting point if you build it and review the codebase.
However if you want to use a different STM32 family then you will need to port the project to your specific hardware.
Also if you have a different WiFi module, you will need to rewrite the drivers to fit to your hardware configuration. (You can only use a WiFi module which supports TLS connectivity, as that is mandatory for the AWS IoT Broker connection).
Another approach: in the AWS console under IoT Core > Device Software > FreeRTOS Device Software (https://eu-west-1.console.aws.amazon.com/iot/home?region=eu-west-1#/software/freertos) there are preconfigured packs for download. Alternatively you can also customize a device pack for download. You will be able to find the same device (STM32L475 Disco board) listed there.
I have a need to poll for a close-to-real time reading from a serial device (using ESP32) from a web application. I am currently doing this using Particle Photons and the Particle Cloud API, and am wondering if there is a way to achieve similar using Google Cloud IoT.
From reading the documentation, it seems a common way to do this is via PubSub and then to publish to BigQuery via DataFlow or Firebase via Cloud Functions. However, to reduce pricing overhead, I am hoping to only trigger a data exchange(s) when the device receives an external request.
It looks like there is a way to send commands to the IoT device - am I on the right track with this? I can't seem to find the documentation here, but after receiving a command it would use PubSub to publish to a Topic, which can trigger a Cloud Function to update Firebase?
Lastly, it also looks like there is a way to do a GET request to the device's DeviceState, but this can only be updated once per second (which might also work, though it sounds like they generally discourage using state for this purpose).
If there is another low-latency, low-cost way to allow a client to poll for a real-time value from the IoT device that I've missed, please let me know. Thank you!
Espressif has integrated Google's Cloud IoT Device SDK which creates an authenticated bidirectional MQTT pipe between the device and IoT Core. As you've already discovered, you can send anything from the cloud to the device (it's called a "command" but it's just an MQTT payload so you can put almost anything you want in it) and vice versa (it's called "telemetry" but again it's just an MQTT payload). Once incoming messages from devices reach the cloud, pubsub can route them wherever you want. I don't know if I'd call it real-time, but latencies in a good WiFi network tend to be under a second.
I'm making a project where temperature and humidity levels are sensored by Arduino and send those data to AWS with ESP-8266-01s. At the same time, those data are also shown on the web application (it may be on Node.js/Java, etc.).
So what I'm asking is how the architecture should be. What is the best practice? Does AWS also provide a web app where I can use it for both database cloud as a web application or should I make a separate project as a web app to connect to AWS?
I searched on Google but the only answers I can find are two ways: Arduino and AWS without another aspect connected to it in my case the web app.
Make use of MQTT protocol.
Components required -
Pubsubclient.h library on esp8266 that will be used to publish temp and humidity data to MQTT Broker on AWS
mosquitto MQTT broker setup on AWS used to accept data from esp8266
Python script that will subscribe to data from the mosquitto broker and dumps into any database(my suggestion is influxdb)
Graphing platform to query database and display visual timeseries-graphs(my suggestion grafana)
Use AWS only for purchasing a virtual machine. Rest can be taken care using open-source Platforms.
Assuming you want to display graphs of temperature and humidity, Using grafana is the best practice.
You will not find a silver bullet here. A proper architecture for your case depends on many things and there can be different approaches with their own pros and cons.
There are many aspects to cover including connectivity, security, update, availability, costs.
Usually IoT devices are not connected directly to the cloud, because they don't have a constant connection, or any network connection. There is a hub (or middleware) that collects data from sensors/devices and send them to the cloud for processing.
But many cloud vendors provide some out of the box complex solutions here (including AWS).
I listed just examples.
Upon using the Google Cloud IoT Core platform, it seems to be built around the idea of sending configurations down to the device and receiving states back from it.
Google's own documentation suggests using that approach instead of building around sending commands down (as a config) and getting responses back (as a state).
However in the very end of the documentation they show an example of exactly that.
I am struggling to understand how does one support both approaches? I can see the benefit of how it was designed but I am also struggling to understand how would one be able to talk to the device using such an idiom of values and results as the config.
Has anybody implemented a command/response flow? Is it possible to subscribe to the state topic to retrieve the state of the device in my own application?
Edit based on clarifying comment below:
We've got a beta feature we're calling "Commands" which will do the reboot you're talking about. So the combination of config messages (for persistent configuration that you want to send a device on startup/connect to IoT Core) and Commands for fire and forget like a reboot message can do what your'e talking about. Current state is a bit trickier, in that you could either have a callback mechanism where you send a command to ask, and listen on the events/ channel for a response, or have the device report state (/state/ MQTT topic) and just ask IoT Core's admin SDK rather than the device.
Commands just went open beta, you should have access to it now. If you're using the gcloud SDK from command line, you'll need to do a gcloud components update and then gcloud beta iot devices --help will show the commands group. If you're using the console, when you drill down to a single device, you should now see "Send Command" next to "Update Configuration" on the top bar.
Old Answer: As a stab at answering, it sounds like rather than using the state topic, you could/should just use the standard /events/ topic and subscribe to the Pub/Sub topic the devices go into instead?
It really depends on the volume and number of devices we're talking about in terms of keeping that state machine in sync.
Without knowing what specifically you're implementing, I'd probably do something like send configs down, respond from device on the /events/ topic, and have a Cloud Function that tracks the Pub/Sub topic and updates something like a Firestore instance with the state of the devices, rather than using the /state/ topic. Especially if you're doing something in response directly to the state reporting of the device.
Send command to device
To send a command to a device, you will need to use the sendCommandToDevice API call.
Receive command from device
To receive a command from a device, subscribe to the /devices/<your-device-d>/commands/# topic.
Full examples will eventually be published to the Google Cloud IoT Core samples repos:
Java
NodeJS
Python
Some background
I'm working on a project that involves a standalone LAN network with number of linux PC's and 1 central windows PC. I need to write web services (right now I got some examples work with jersey in java) for both the linux PC's and the central window PC. I'm wishing to publish an API Gateway in the central PC, which will need to know the addresses and ports of the other PC's so he can address their REST services.
The question at hand
My question can be seperated into 2 parts:
1) How will I make service discovery work? The option I know about from my research till now is:
Using etcd. Seems easy and simple, but I don't see the benefit of it over managing a database in the API Gateway and publishing on it routes for registering and deregistering services.
2) How will the other linux PC's services will know the address of the central windows PC? I read many articles about the service discovery pattern, and failed to find a single one that address the part about how exactly the services know the address of the service registery. Lets assume that the address is fixed in the LAN and doesn't change while my system should be working, but I don't know it when deploying (My clients need to deploy it in several different LANs where the address of central station can be different, and I can't trust them to define it in a config before deploying)
Thanks a lot in advance for any assistance :)
I don't have the reputation to answer but I am interested in this question for similar reasons.
You might find this question and answer useful on programmers stackexchange which talks about a broadcast approach.
I'm researching etcd and Netflix eureka and trying to understanding if this could be applied on the local LAN.