Packet loss in mesh network

[Cooper]

I use the nRF OpenMesh from the GitHub. (https://github.com/NordicSemiconductor/nRF51-ble-bcast-mesh)

My mesh network just has two mesh node, node A and B. I made A node as a broadcaster, B node as a receiver. "MESH_INTERVAL_MIN_MS" setting to 20. And I send a mesh packet every 200ms from A node. But in this low broadcast speed, it still has packet loss issue. About 10~20s loss one mesh packet. What is the problem?

Is it possible that the scan interval and scan window size doesn't match the advertising interval? If so. How to modify the scan interval and scan window size?

And what is the default value on scan interval and scan window size?

[Hung Bui]

The Openmesh doesn't use Softdevice, so there is no scan interval or scan window. The device stay in scanning mode all the time. But of course there could be chance that it might catch other packet from other peer, or a corrupted packet or interference that it can't detect a packet.

Again, it's RF. It's impossible to guarantee on 100% packet delivery. That's why we need the trickle algorithm to re-transmit broadcast data in a power efficient way.

Why it's important for you that all the packets should be received ? and re-transmission is not OK ?