How to test if a TLS handshake is successful


Microsoft Azure is changing its root certificate for IoTHub and we have to do some testing with this new certificate on a specified endpoint. Specifically : The credentials for the test environments are:

More info here.

I am successfully doing this with MQTTfx by tracing all messages via wireshark

but I can’t do this with the modem and it returns +KTCP_NOTIF: 1,13 everytime.

Is there a way I could know if a TLS handshake has been made?

Other than the new root certificate now SHA384 might be used (Microsoft claims sha256 will work also) which the HLxx series supports.


Hi @hkiol
For this case, can you please share with me the wireshark capture when device failed to start a TLS connection to server?

Hi @jerdung ,

Do you mean the wireshark capture of the device with the modem? How would I do that since the device tries to connect to an external server?


Hello @jerdung ,

This is quite important as it has to do with Azure connection which I am sure a lot of people are interested in.

Is there a way I can see the internal messages from the modem and see if the TLS handshake has been achieved?