Comparison of IMAP and POP

IMAP is a protocol which shows the updated data it doesn’t matter from any device you access. IMAP works in both online and offline mode of operation. Clients using IMAP leaves the message on the server until the user deletes them.
Pop is a protocol which depends on the device. If the user makes some updates on one device then that update will not show on other device.

Advantage of IMAP over POP

• Pop internet protocol allows the email client to connect to the server for a short period of time while using IMAP4 client can stay connected as long as the user interface is active and down message content on demand. When user wants to open many or large messages this IMAP 4 results in a faster response times.
• The Pop protocol allows making changes in the currently activated account to the mailbox. IMAP allows access to multiple email accounts at the same time and provide mechanism for client to detect changes made to the mailbox by other clients.
• All the internet email message is transmitted in MIME format, where each message has the structure of the trees and there are various parts of message like attachment as leaf of tree. IMAP protocol allows the client to retrieve the individual portions of messages without retrieving the attached files.
• By using the flags defined in IMAP the email clients can keep track of message state. These flags are stored on the server so that different client can detect changes to the same mail box made by other clients. Whereas PoP does not have the facility to store information on the server.
• IMAP allows the clients to create, rename and delete mailboxes on the server and copy messages between mailboxes. Multiple mailbox support allows servers to provide access to shared and public folders.
• POP 3 is inadequate for the mobile user. As the message one downloaded will be accessed from the computer only.

Disadvantages

• IMAP is very complex to maintain and some of the clients do not support the protocol.
• IMAP is slower to load messages than IMAP
• IMAP is available online whereas POP can be used offline.
• POP 3 emails are easily manipulated because they exist on the user local machine.
• Some email programs have difficulty in supporting IMAP
• IMAP uses the host user hard drive space and enforce storage quota for their users.