Guts of a Mail Server: What is it and how does it work?
What's a Mail Server?
“What exactly is a mail server?” Considering how widely-used email is, and how technical it gets, this is not a question you should be embarrassed to ask. So, what is a mail server, then?
A mail server is a dedicated computer with a static IP address that your mail client (Gmail, Outlook, Apple Mail) talks to via SMTP and either POP3 or IMAP, and which uses a special program to route, receive, and store messages. That’s all simple enough but not exactly what you want to know. To understand what makes a mail server special, let's break it down:
A physical server
A good computer on a robust network switch with a high-bandwidth Internet connection and a static IP address.
The MTA, or mail transfer agent, is the program that turns your words into something ready to travel the Internet.
It accepts messages...