mesh Configuration

[MK Chen]

The relay successful rate of my Mesh setup is not 100%. I think light server miss packet from light client. I have tried to change configuration following:

1  #define BEARER_SCAN_INT_DEFAULT_MS 700 (default 2000) ;

2 #define BEARER_SCAN_WINDOW_DEFAULT_MS 700 (default 2000) ;

But it seems performance no much difference. May consult how to optimize Radio configuration in order to scan 37, 38, 39 channels fast effectively?

Thanks

MK Chen

[Hung Bui]

Hi Chen, 

What is the success rate do you have ? 

Do you have any retransmission for a packet you send ? In our example (light_switch) we have APP_UNACK_MSG_REPEAT_COUNT  = 2 

Changing BEARER_SCAN_INT_DEFAULT_MS  and BEARER_SCAN_WINDOW_DEFAULT_MS  wouldn't help since we already scanning at 100% 

Regarding RSSI filtering, you can filter after the message arrived in access layer, but not in the radio or in network layer.

[MK Chen]

directly without relay: successful rate is 100%

one hop relay:  successful rate is 90%

two hop relay: successful rate is 50%

[MK Chen]

Dear Hung Bui,

I checked node_setup.c, but this file is not inside project, so current light switch is not this method to get TTL?

Thanks

MK Chen

[Hung Bui]

How do you provision your mesh network ? 

[MK Chen]

using nRF Mesh mobile app.

Would you mind to provide more detail:

1 how to get TTL value in light switch server mode?

2 how to get  APP_UNACK_MSG_REPEAT_COUNT in light switch server mode?

3 where should be added RSSI filter at access layer?

Appreciate your help. Thnaks 

[Hung Bui]

If you setting up using the mobile app (I'm testing on Android) you can find the TTL setting when configuration the publication setting of the Generic OnOff server. 

You can also configure the number of retransmission on the network layer in the same window.

3. I don't think adding access layer RSSI filtering would help here. 

[MK Chen]

the purpose of adding RSSI filtering is to filter signal beyond adjacent relay note, to verify performance of BLE-Mesh relay feature. 

[Hung Bui]

Okey, my understanding is that you will not relay those message with very low RSSI to avoid network traffic. This is fine but it will reduce the redundancy capability of the network. 

To do this you can have a look at network_packet_in() inside network.c, you can find RSSI inside p_rx_metadata->scanner.rssi. Then you can choose to do packet_relay() or not.