Prepare the private key and self-signed X-509 certificate. For this purpose, the OpenSSL utility could be used. By executing the command openssl genrsa -out server.key 2048, the private key derived with the use of an RSA algorithm is generated to the file server.key. Based on this private key, the X-509 certificate could be generated by calling openssl req -new -x509 -sha256 -key server.key -out server.crt -days 365. The server.crt file is created.