Is Dovecot required for mail server like Exim or Postfix?

Question

I am really confused about this, because I thought Exim and Postfix can authenticate user logins and nothing is required. Reading the page at

https://www.digitalocean.com/community/tutorials/how-to-install-and-setup-postfix-on-ubuntu-12-04

It states:

" Conclusion

Once Postfix is installed, mail can be sent to and from the server, although without a mail server like Dovecot or Cyrus, you will only be able to see the email on the server. "

Now reading at Dovecot's main site http://www.dovecot.org it states:

"Dovecot is an open source IMAP and POP3 email server for Linux/UNIX-like systems"

So does it mean that if I want to read the email messages using my desktop email client software, this is absolutely required due to IMAP and POP3?

Is SMTP protocol used by a mail server like Postfix or Dovecot?

Thank you.

Answer 1

SMTP protocol is used to accept and relay email, but is not used for email reading.

So - when you authenticate to SMTP, server can accept your emails and forward them to other MX servers, but cannot let you download existing mails from the server.

If you want to read emails on your mobile phone or your PC you will need to use IMAP or POP3 protocol. To enable reading emails - you will need to set up Dovecot (or some other service that serves POP3/IMAP).

Also, in the ever expanding wireless network access, I would advise you on setting up mandatory IMAPS and/or POP3S - those are ssl encrypted variants of IMAP and POP protocols. Email is a private stuff and should be hidden from curious eyes sniffing the network ;)