How Email Works: Understanding the Basics
1. What Is SMTP (Simple Mail Transfer Protocol)?
SMTP (Simple Mail Transfer Protocol) is the standard protocol used for sending emails across the internet. It handles the transmission of messages from the sender's email client or server to the recipient's email server. SMTP operates on port 25 by default (or ports 465/587 for secure connections) and ensures reliable email delivery by following a set of rules for communication between servers.
2. Why Should You NOT Host Your Own Email Server?
Hosting your own email server can be complex and risky due to challenges like maintaining security (spam, phishing, DDoS attacks), ensuring high deliverability (avoiding blacklists), and handling infrastructure costs (uptime, backups, scalability). Most businesses and individuals prefer using third-party providers (e.g., Gmail, Outlook) for better reliability and reduced administrative overhead.
3. What Are the Key Components of Email System Design (SMTP, IMAP, POP3)?
An email system relies on multiple protocols:- SMTP: Sends emails between servers.- IMAP (Internet Message Access Protocol): Allows users to view emails stored on a server across multiple devices (syncs in real-time).- POP3 (Post Office Protocol): Downloads emails to a local device, deleting them from the server by default.Advanced designs may also include spam filters, encryption (TLS), and APIs for integration.
