IMAP4 (Internet Message Access Protocol 4) is a protocol used to retrieve e-mail from the mail server and defined in that RFC 3501.
What is IMAP (Internet Message Access Protocol)?
IMAP was developed in 1986 by Stanford University. By default, IMAP uses TCP 143 port and uses TCP 993 for a more secure connection. This protocol is the latest version of the advanced IMAP.
Another protocol used to receive e-mail from a server is POP3. In the previous article, we have provided detailed information about POP3. In this article, we will talk about IMAP4, the e-mail retrieval protocol.
Emails downloaded by a client using the POP3 are also deleted from the server when deleted in the mailbox. However, emails downloaded with the IMAP4 are not deleted from the mail server when deleted from the mailbox. Therefore, the server needs high storage.
The Internet Message Access Protocol 4 generally recommended for small businesses because e-mails are backed up at a central point. The working logic of IMAP4; if a user decides to delete a message after receiving a message from a mail server, the message stores on the mail server, and the user can access the message from any device.
In a structure that uses IMAP4, received emails are backed up and synchronized only on the mail server. As a result, a user can see these emails when they access their mailbox from other devices.
IMAP4 offers many advantages over POP3. As a result, the email control better provides with IMAP4.
Internet Message Access Protocol 4 Features
Let’s examine the characteristics of this protocol, respectively:
1. A user can create, delete, and rename customized mailboxes on the mail server.
2. A user can check the Mail header before downloading an e-mail.
3. A user can change e-mail properties. For example, E-mail messaging, marking, and so on.
4. A user can partially download the E-mail content. For example, if E-mail contains multimedia items, E-mail may be partially downloaded because of a bandwidth issue.
5. The user can create an E-mail hierarchy in the mail area.
Difference Between IMAP4 and POP3
You can compare the difference between IMAP4 and POP3 from the following table.
Email Reading Capability
Server Resource Usage
Mobile User Experience
User Control over Download
Partial Email Downloads
A user uses the SMTP protocol when sending e-mail. SMTP also establishes a connection between two servers. However, when the user wants to receive e-mail from the E-mail server, it uses the IMAP and POP3 protocols. The POP3 protocol is widely used because of the increased use of mobile devices. Thanks for following us!