Email: POP & IMAP

POP and IMAP are used to retrieve email from an email server. Either one can be used. Let’s discuss both.

POP

The most commonly used version of the Post Office Protocol (POP) is version 3, or POP3. This is how it works:

POP Phases

Emails are simply downloaded from the server in 4 phases: connect, authorize, transaction, update.

1. Connect: The user agent first connects to the POP3 server on TCP using port 110.
2. Authorize: The user agent authenticates

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