|The Java Apache Mail Enterprise Server (a.k.a. James) is a 100% pure Java SMTP and POP3 Mail server and NNTP News server designed to be a complete and portable enterprise mail engine solution. James is based on currently available open protocols.
Apache James is released under the Apache Software License, Version 1.1.
More information about Apache James can be found at: http://james.apache.org/
The latest Apache James version can be downloaded from: http://james.apache.org/download.cgi
Explanation SMTP server
IMAP (Internet Message Access Protocol), port 143
POP3 (Post Office Protocol), port 110
SMTP (Simple mail Transfer Protocol), port 25
- A user Jack in domain foo.com sends an email to [email protected] using the Thunderbird mail client.
The mail client sends the message to the mail server using the SMTP protocol.
The SMTP server receives the message and checks if the message is for the local domain.
If the message is for [email protected] it is delivered to the mailbox belonging to Smith.
- If the message is for a foreign domain the DNS server is queried looking for the MX (Mail Transfer) record for mobilefish.com.
The DNS server returns the ip address of the mobilefish.com SMTP server.
- The SMTP server relays the message to the other SMTP server using the SMTP protocol.
- The SMTP server receives the message and checks if the message is for the local domain.
If the message is for [email protected] it is delivered to the mailbox belonging to Robert.
- The SMTP server administrator in the mobilefish.com domain only allows users to access their mailboxes using the POP3 protocol instead of the IMAP protocol. For both protocols users must always authenticate before they can access their mailbox.
POP3 (Post Office Protocol)
By using this protocol the mail is forwarded to the user machine and does not remain in the SMTP mailbox. The user can go offline to read the email.
IMAP (Internet Message Access Protocol)
By using this protocol the mail remains in the SMTP mailbox and is not downloaded on the user machine.