Get physical source of intermediate relay messages

[Mathias]

Hi!

I have a question about the Mesh SDK. Is it currently possible to get the physical source of a relayed message (thus the relay that send it) out of it? I only seem to able to get out the initial sender and ultimate receiver out of the network packet metadata. I want to visualize the path a packet has taken through the network and thus need the intermediate relay sources for that as well.

Thanks in advance!

Kind regards,

Mathias

[ovrebekk]

Hi Mathias

There is no built in mechanism for this, no. Since there is no routing in the mesh, having this included would add quite a lot of overhead to the communication.

You might be able to add a proprietary system on top, where each node can report that it received a packet, and what the TTL counter was at the time, but this would have to be added in the application.

Best regards
Torbjørn

[Mathias]

Sounds like a great idea, thanks for the answer and clarification!

[ovrebekk]

I am happy to help. The best of luck with your project :)

[Mathias]

Hi Torbjørn

After some thought, we came to the conclusion that looking at the TTL counter alone could still give situations where a node doesn't know where packets come from. We then looked a bit further still and found a possible solution that I put in the answer below.

[Mathias]

We ultimately found out that we could use the BLE GAP Advertiser address that is in the metadata of the received packet, to find out which physical source relayed the specific packet. We then used the function in core.tx to change the advertister address for both roles to something more readable. Not fully BLE standard but it's just for measurements. Thanks for your help again Torbjørn!