Build simple mesh network.

[twar]

Hello.

I am trying to build something like this in the picture below:

so my guess is that I need mesh functionality.

So my initial questions are.

Are there any tutorials describing how to connect those nrf52 into mesh network? How to customize criteria for adding nodes, let say some kind of key authentication before adding node to such network?
How co communicate with individual nodes from perspective of "Relay node"?

I tried to compile this example -> github.com/.../Nordic-Thingy52-mesh-demo but it seems like mission impossible, it seems that there is some next issue to fix, missing headers files etc.

For example I would like to get temperature from every node in such network. Any ideas where to start?

Best regards.

[Rorisang]

Hi. I can only tell you how to set up the mesh network but as a beginner, i can only do the demos : light switch and dimming examples. Do you need that or you are past that stage?

[twar]

Hi.

I would be good start, so yes please. :)

[Bjørn Kvaale]

Are you sure that you require mesh? From the diagram, it seems that all of the nRF52 "peripheral" devices are the same length from the relay "central" device. Will this be the case or not? Remember that mesh is not low power, since the radio must be on almost all of the time to listen to incoming messages (I am referring to regular nodes, not low power nodes).

I would take a look at the multilink example first if I were you. It is a lot easier to understand than mesh & allows for low power implementations because the links are just regular BLE links.

Let me know if this would work. Otherwise, if you really want mesh, we can discuss this.

[twar]

@Bjørn

Thank you for answer. I'll try that solution but I would really like to check this mesh thing and learn at least basics of its functionality. How to configure such network so that only chosen nodes can access, how to address request for some data to specific node etc.

[Bjørn Kvaale]

Are there any tutorials describing how to connect those nrf52 into mesh network?

 There are multiple tutorials explaining this. For starters, I would take a look at the light switch documentation from mesh sdk v2.2.0. Then, I would also take a look at this Youtube video & the links in the description.

How to customize criteria for adding nodes, let say some kind of key authentication before adding node to such network?

 Take a look at the source code from the Youtube video. There, the Thingy node blinks a certain number of times & you need to authenticate this in the nRF Mesh app. However, there is also security in the mesh example itself to make sure that the communication is secure (e.g. app keys, device keys, network keys).

In addition, you should be able to use NFC on the 52 DK to enable extra security. You would need to merge the mesh sdk example with one of the nfc examples to get this to work.

How co communicate with individual nodes from perspective of "Relay node"?

 I do not understand this question unfortunately. The relay node only relays information, such as a unicast or broadcast message. If you want to communicate with individual nodes, I would take a look at unicast messaging.

I tried to compile this example -> github.com/.../Nordic-Thingy52-mesh-demo but it seems like mission impossible, it seems that there is some next issue to fix, missing headers files etc.

For example I would like to get temperature from every node in such network. Any ideas where to start?

Start with the standard light switch example. Try to provision with the provisioner, a client & a server (using the provisioner, client & server examples) first. Then, once that has worked, try the same with the nRF Mesh application (see the youtube video). Use a proxy client & proxy server example instead. 

What you can also do is take a look at the github code located here. Take a look at the included pdfs. Hope that helps!