What is the best way to start using mesh proxy with a ble peripheral using gatt

[Christopher Hunt]

Hi there,

My question is similar to https://devzone.nordicsemi.com/f/nordic-q-a/39447/central-role-in-a-mesh-proxy-node, but perhaps slightly different in that my existing BLE sensor provides a GATT service.

What I'd like is for my existing GATT service to advertise, a mesh proxy to connect, and then have that mesh proxy forward the GATT service's traffic across the mesh. So:

1. BLE sensor with GATT service X advertises
2. nRF52840 node with the proxy feature connects to devices advertising GATT service X
3. requests received at the proxy for the BLE sensor are forwarded to it over GATT
4. replies/notifications received at the proxy from the BLE sensor are forwarded over the mesh

Is there an example that provides this functionality "out of the box", or am I looking to write a program combining regular BLE calls with mesh calls and handle the translations?

Thanks for any help.

Cheers,
-C

[Hung Bui]

Hi Christopher, 

What you described is more likely the feature for Friend and Low Power Node (LPN) not for proxy and GATT device. 

There is no caching when doing Proxy. 

I would suggest to make the BLE sensor works as LPN node and if you need GATT it can do GATT in addition to LPN mesh role. 

[Christopher Hunt]

The BLE sensor is an Android tablet and hasn't got the ability to act as an LPN node, well, at least there's no software that I can find to make this happen. I also want to avoid changing the Android tablet as it can be communicated legitimately without the mesh network i.e. from another phone or tablet.

Perhaps I should treat the BLE sensor as per any other peripheral attached to my nRF52840 node i.e. have the node provide a dynamic set of services, even of the same type, in relation to the number of BLE sensors it can find... Do you see any problems with taking such an approach?

[Hung Bui]

Okey, I didn't know that the BLE sensor is an Android tablet. 

In that case I would think that you should do normal GATT and then has some proprietary code on the proxy node to convert (and cache) GATT messages from and to the BLE sensor.