@DianeTrout: I was finally able to get a wireshark capture of an unsuccessful connection attempt (thanks for your help Diane!), and I can confirm that "unknown 15" is present in the Client Hello handshake protocol.
@DianeTrout: I was finally able to get a wireshark capture of an unsuccessful connection attempt (thanks for your help Diane!), and I can confirm that "unknown 15" is present in the Client Hello handshake protocol.