The Diffie-Hellman key exchange parameter in nginx usually a file named dhparams.pem that provides better security during the exchage of the ssl encryption keys. One can generate this file with the following command:
openssl dhparam -out dhparam.pem 40964096 bits is recommend to avoid the logjam attack: https://weakdh.org/. This file includes the prime p and the generator g. IT IS SAFE TO MAKE THIS FILE PUBLIC You can learn more here: https://www.youtube.com/watch?v=NmM9HA2MQGI
