What Is Internet Message Access Protocol? How Does It Work?
What Is Internet Message Access Protocol
What is Internet Message Access Protocol? Internet Message Access Protocol is also called IMAP. The Internet Message Access Protocol is an application-layer protocol that operates as a contract to receive email from a mail server.
It is a remote access mailbox protocol designed by Mark Crispin in 1986, the current version of IMAP is IMAP4. It is used as the most common protocol for retrieving emails. The term is also known as Internet Mail Access Protocol, Interactive Mail Access Protocol, and Temporary Mail Access Protocol.
How Does Internet Message Access Protocol Work
As an incoming email protocol, IMAP acts as an intermediary between email servers and email clients. When users read emails using IMAP, they read them from the server. They don’t download or store emails locally on the device. This means that email is not tied to a specific device and users can access it from anywhere in the world using different devices, for example:
The following are the general steps and procedures involved in an IMAP operation:
- When a user logs into an email client, such as Microsoft Outlook, the client uses IMAP to contact the server.
- Connections are made on specific ports.
- The headers of all emails are displayed by the email client.
- IMAP downloads messages to the client only when the user clicks; attachments are not downloaded automatically.
- Users can check their mail faster with IMAP than with other email retrieval protocols, such as Post Office Protocol 3 (POP3).
- Emails will remain on the server unless the user explicitly deletes them.
- The IMAP server listens on port number 143, while IMAP over Secure Sockets Layer (SSL)/Transport Layer Security assigns port number 993.
Features of Internet Message Access Protocol
The following are the features of the Internet Message Access Protocol:
- It can manage multiple mailboxes and organize them into different categories.
- It can add a message flag to keep track of the message being viewed.
- It can decide whether to retrieve emails from the mail server before downloading.
- It can easily download media when multiple files are attached.
Advantages and Disadvantages of Internet Message Access Protocol
Advantages of Internet Message Access Protocol
Most implementations of IMAP support multiple logins. This enables users to connect to the email server from different devices at the same time. For example, users can access their email using both the Outlook app on the iPhone and the Outlook desktop app.
Multiple access is not possible with POP3, where the downloaded email disappears from the server and thus cannot be accessed from other devices later. Therefore, POP3 is only useful when users access their email from the same device each time.
IMAP provides greater access flexibility for users who travel frequently or need to view email from different devices or locations. The protocol doesn’t specify how to handle multiple connections, it’s left to the developer of the mail client.
In a conclusion, the advantages of Internet Message Access Protocol are as follows:
- Email accessible from multiple devices
- Fast and efficient access
- A mailbox can be shared by multiple users
- Users can organize emails on the server by creating folders and subfolders
- support email functions such as search and sorting
- The IMAP server supports the IDLE extension (push mail), so mail appears as unread in the inbox without setting a polling interval or requiring the user to hit receive first and can be used offline.
Disadvantages of Internet Message Access Protocol
Here are the disadvantages of Internet Message Access Protocol:
- IMAP is complicated to maintain.
- The user’s email is only available when there is an internet connection.
- Loading messages is slow.
- Some emails do not support IMAP and are therefore difficult to manage.
- Many browser-based solutions are not available due to a lack of IMAP support.
Originally published at https://www.minitool.com on August 8, 2022.