Sniffing Thread Coap example with Wireshark

[Fabian Frei]

I have the Thread Coap examples running on two nRF52840 dev kits (coap server + coap client). When I try to check the coap traffic with a sniffer + Wireshark, Wireshark can only decode the 802.15.4 frame. It does not recognize the CoAP messages.

Then there is an expert info in Wireshark which says "No encryption key set - can't decrypt". So, I guess the 802.15.4 traffic is encrypted.

I tried to set "mode.mSecureDataRequest" in the "thread_init" function to "false", but it did not seem to affect the 802.15.4 encryption.

Is there a way to either disable encryption or set an according encryption key in Wireshark?

Thanks in advance!

[Jørgen Holmefjord]

Are you using the nRF52840 OpenThread based sniffer? Did you setup Wireshark as described in the documentation, with the decryption key?

[Fabian Frei]

No, I used a freescale USB sniffer. I followed the instructions and it worked. Thanks!