Understanding How Email Works on the Internet

Introduction to Email Protocols

• Email is a common service used frequently, but its transmission across the internet involves various protocols.
• This discussion uses an example featuring two individuals: Greg and Ziz.

Key Concepts in Email Transmission

Email Servers

• Each email address is associated with an email server.
• Example: Greg uses [email protected], Ziz uses [email protected].
• Email servers are essential for sending and receiving emails.

Initial Communication

• When Ziz sends an email, her computer interacts with the Gmail server.
• The Gmail server is informed of the intent to send an email to Greg's hotmail.com address.

Email Protocols

IMAP and POP

• IMAP: Internet Mail Access Protocol
• POP: Post Office Protocol
• These protocols help mail clients (running on computers) communicate with mail servers.
• Functions include retrieving, sending, organizing mail, and more.
• They run the first step in sending an email.

SMTP

• SMTP: Simple Mail Transfer Protocol
• Used by mail servers to communicate with each other.
• Gmail uses SMTP to send Ziz's email to Hotmail's server.
• Handles error messages (e.g., wrong username) and ensures message delivery.

Email Delivery Process

• Once Ziz's email is sent, it arrives at Hotmail's server through SMTP.
• Greg's computer uses IMAP or POP to check for new messages on Hotmail's server.

Conclusion

• Email transmission is a collaborative process involving multiple internet protocols.
• Despite being a simple task, sending an email involves complex interactions between different protocols and servers.