Does someone know the bare minimum required for a device to connect to the Azure IoT Hub and to send and receive messages (in terms of memory usage, processing power etc.). Or is this really case-specific?
I couldn't find a conclusive answer on the web. Does someone have experience with this?
Many thanks!
Does someone know the bare minimum required for a device to connect to
the Azure IoT Hub and to send and receive messages (in terms of memory
usage, processing power etc.).
As #juunas pointed out, it is hard to say precisely.
But you can check from the following two aspects(I assume you mean devices that communicate directly with Azure IoT Hub)：
Using Azure IoT SDKs, the device needs to be capable of establishing an IP connection, support TLS, have at least 64KB of RAM ...
Using REST api, the device can connect to the Azure IoT Hub and to send and receive messages directly over the Internet from any application that can send an HTTPS request and receive an HTTPS response.
There's nothing like system/set-up requirements for Azure IoT Hub so there's no specific document from Microsoft talking about this topic. Depending on your target application you can pick the device, as all descent embedded devices can act as IoT device for Azure.
You can take a look at Azure Certified IoT device catalogue and find out whether particular device is listed under that.
MS has published 2 Whitepapers on this. You may find this useful
Evaluating Your IOT Security
The right secure hardware for your IoT deployment
Related
I want to implement the following system.
There are users and each user will have an IoT device. The user should be able to do the following:
Login with their email and password.
Control the IoT device in real time (the user will perform some operation on the IoT device and the result will be displayed instantly on the app).
See the state of IoT device in real time. If something changes on the IoT device it should reflect on the app in real time.
I was wondering if this is doable using azure IoT Hub. I came across an architecture where the device is connected to IoT hub and the app is connected to signalR. The messages from IoT device will go to IoT Hub which will update the app using signalR.
But is there any way we can not have additional component like signalR? Can IoT device and mobile app be connected directly to azure IoT hub and exchange data between them without an entity in between other than IoT hub?
Connecting mobile app to IoT hub seems like an option but I did not find any way to implement email and password based authentication to allow users to connect to IoT hub.
Any help in this regard is appreciated.
You could absolutely go without SignalR. You can use the IoT Hub Service SDK to send C2D messages to your device from your phone, and also listen to the device telemetry with the same SDK.
However, it would probably be a better idea to have some restrictions on what you can do with that SDK. If the user first has to log in, I take it that they don't get access to every device in your application? Using some kind of role-based access might be preferable, you would build an API for that, which then uses the Service SDK to give you the data.
Also, even though you could listen to the device data directly from your phone, that means that if you have bad reception/wifi, data might not be received. You might want to consider storing it somewhere? I don't know the details about your application, but if you would then want to listen to events from that storage and send it to your app... SignalR might not be the worst idea.
"See the state of IoT device in real time. If something changes on the IoT device it should reflect on the app in real time."
For this EventGrid integration (https://learn.microsoft.com/en-us/azure/iot-hub/iot-hub-event-grid ) would help. For realtime telemetry as Matthijs said SignalR would be a better choice.If you are fine with some delay (say 10 sec) then Azure Time Series Insights can also be used.
Right now, on IoT Hub there is an information that limit for messages per day 8000. I would like to ask you about any patterns which are being used in Azure.
I am curious if I am able to hit to Azure with some service outside Messages in order to prevent it from being overloaded by big amount of data, or save some confidentiality for this service.
For example, I would like to store some data from given service to Messages that are not being confidential and other data by using some WebSocket or any Rest protocol. I think that there are some patterns that serve that scenarios.
Does anyone has experience with that kind of situation?
Not everything needs to go through IoT Hub. IoT Hub is great for two way communication to/from IoT devices. You could also look at Event Hubs for ingestion from devices that don't need two way comms. We have a write up on the differences here Connecting IoT Devices to Azure: IoT Hub and Event Hubs.
How can an IoT device which connects to an IoT Hub using the Azure IoT Hub SDK retrieve larger amounts of sensitive data which is part of the device configuration?
I know i can use Device Twins as configuration documents per Device, but those are limited to 8K in total.
I need larger amounts of data in binary format to be transfered to the device when i a device - for example - gets reset to factory defaults or somehow loses it's local storage as part of a hardware fault.
I was thinking about using a D2C method triggering a request which results in a series of C2D or direct method calls to the requesting device transmitting the information in question (basically mimiking request/response behavior). However this feels like a workaround.
My other thought was about transmitting urls to a storage account as part of the device twin properties allowing the device to download the binary information using the Storage SDK, however given the sensitive nature of the information downloaded i can't directly expose this information to the internet using a public accessible container in Azure Storage.
So my last thought was to access a REST API which controls access to the information. However my concern is, that i break out of the secure communication channel, the IoT Hub SDK provides with it's build in communication methods and i have to secure the communication between device and the REST API using some kind of rotating secret anyway which could expose other risks along with a complicated custom implementation.
What is the suggested way of providing access to this kind of device-specific data for Azure IoT Clients?
I do recommend to use a new feature (still in the preview) of the Azure IoT Hub such as a Device Streams.
You can test this new preview feature using my updated tool Azure IoT Hub Tester (see Appendix A2)
So, I am working on an IoT solution on Azure, we have been using a partner solution where we had the partner's devices linked to his cloud solution that exposes the data to us Via REST services. Right now we want to have our own IoT Cloud Solution on Azure.
At first, I am planning to build a Bridge between our IoT Solution and the partner's cloud solution via its REST Services that will link to our IoT Hub in order to ingest the data to our cloud.
Also, the data will not be only telemetry data but we'll have to send commands as well to those devices.
My question: I would like to know what would be the appropriate technology/solution to use a gateway (Data Grid, Azure Function, Azure WebJob)
The numbers in the picture represent the step that I am considering to tackle this problem.
1- First we are implementing an Application gateway that will have to get the data from the partner's system and sending commands to their system. It will allow us to first build the other components of our system and make sure that it can handle what is in place right now.
2- Second, the partner's devices will connect directly to a device gateway that is connected to our IoT Hub. In this case, we will not be using the gateway made in 1 anymore.
3- Finally, we will have our own devices connected to our IoT Hub, the partner's devices will always be connected to our IoT Hub via the gateway built in 2.
Let me try to answer your questions in the order you have asked.
For application gateway, where you are trying to pull data through
REST, you can use Azure functions and then you use Cosmos DB or any
storage to save data. I see , after getting device data from Partner
network, you are routing it to IoT-Hub (I would not say, its
incorrect), however once we pull data through Rest, we can directly
put into DB. So my Answer is to use Azure functions to pull data
from Partner solutions and put into DB.
If partner device is capable of running Azure IoT sdks or can be
provisioned to send data to IoT Hub directly, this will ease lot of
things and you would be able to send D2C and C2D messages easily.
further, here you can route data to DB by using configuration from
IoT Hub.
For your devices you can use IoT Hub Directly or can use Azure
IoT Edge (device gateway as you pointed ), both are fine , depends
on use case and also if we want to do some edge computation or
analytics at device side. And one important suggestions, use Azure
functions where ever you find that you have to integrate devices
data through Rest. Most cost effective in such scenarios.
Let me know if it clears your doubts.
After some time working on the subject, I did implement an AZURE Function app for the following reasons :
Supports Continuous Deployment and Integration Even though Azure Functions is serverless architecture, it still supports Continuous Deployment and Continuous Integration
Capabilities for implementing code - Being event-driven, the application platform has capabilities to implement code triggered by events occurring in any third-party service or on-premise system.
Compute-on-demand: This delivery model ensures that computing resources are available to the users as per their demand.
I have also used Azure Table Storage as database storage technology.
I have a question about an Azure IoT project based on Windows Azure. In short; it's an embedded application (ARM based device, running on a custom RTOS) who's sending device information to Windows Azure using the recently announced Serverbus Event Hub. It's using the HTTS endpoint of the Event Hub to send it's information to. So for so good.
But now I want to "talk" to the device from the cloud. Basically, I have a website running on Azure, and I want to send commands to that device (which is not 100% of the time connected, as it's an on-the-field device). What's the best way to do this? What technologies can I use?
Do I need to use Sockets, TCP connections, long-polling HTTP requests, ..? The big 'thing' is that the device is running a custom RTOS, so there are no libraries or whatsoever available..
Thanks! :)
You can think about AMQPS and Azure Service Bus Topics/Subscriptions. Create a subscription with a filter (e.g. by device name or ID) for each device and send annotated messages to the topic.
Count of subscriptions limited by 2000 for 1 topic.