I want to use SSL/HTTPS protocol to secure the transmission between my server and my clients but I am not sure how to perform it in a fast and correct way.
From my understanding, if an HTTPS connection is established, I then have to ask the client to authenticate itself so the client is either accepted or rejected. This solution seems to me a bit expensive in time because of the additional authentication messages.
Looking into certificates, I found a field called challenge password. So the question is: Is it safe to use the challenge password to authenticate the client? Or in other words, is the client's certificate encrypted when sent to the server?