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?

[Cooper]

I send packet like you said, use "rbc_mesh_value_set()". And setting "MESH_INTERVAL_MIN_MS" to 20. And I send a packet every 200ms. I use the setting above, and I use sniffer can see there has retransmission twice after each packet sent.

If node B was not listening at right time. Is it possible to change the scan setting? Like scan interval and scan window size. Or we can't modify it?