How to build private and secure mail server
Steps for setting up secure mail server:
Encrypt POP3 and IMAP authentication for privacy concerns
Mail relay configuration
Connections and default settings – To avoid DOS attacks, limit the total no of connections.
Implement Access Control and SMTP Authentication
Maintain local IP blacklists - To block spammers
Activate Reverse DNS to block bogus senders
Great! Thanks for the clarification.