mesh sniffer - NRF52840

[Domneck]

Hi All,

I'm using Ellysis sniffer for debugging my ble mesh network.

I've made network setup using generic on/off application and I'm able to communicate and capture the sniffer log.

In sniffer log I see some packets are with locked symbol and how do I see complete packet. 

Screenshot is attached and what IV index is used in the application and what its?

[Joakim Jakobsen]

Hi. 

I assume this is because the sniffer needs the device keys in order to decrypt the messages, and I don't think the sniffer can sniff the device keys (formed during provisioning).
I believe that the messages you are seeing are the configuration messages. 

I haven't used the Ellisys sniffer myself, but I'll ask internally if there are a way to get around this. 

Best regards, 
Joakim 

[Joakim Jakobsen]

Hi. 

Talked to one of my colleagues; 

You need to open the form with Mesh Security options and add all your pairs key + IV index. That is the same for all kind of keys (network, application, device). After that, the sniffer will decrypt and specialize all Mesh traffic. 

Best regards, 
Joakim

[Domneck]

Thanks for reply..

Yes I've found that option in application and able to decrypt the packet.

I dint understand what is this IV index and why it's used.

Regards,

Domneck