i am new in this forum,and i am intent to do 3 things but i dont know how, if is possible any people help me to do this please?
a) i need to encrytp conecction to port 25
b) i need to permit only 1 IP to connect to the port 25 and reject the others
c) i need to reject mail from peope which there aren't authenticated, ( permit only to send mail people that are authenticated).
Thanks for all.