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This article mainly introduces what are the differences between imap and pop3, the article is very detailed, has a certain reference value, interested friends must read it!

Difference: the POP3 protocol allows the e-mail client to download messages from the server, but the actions on the client are not fed back to the server. IMAP provides two-way communication between webmail and the e-mail client. The operation of the client will be fed back to the server, and the mail on the server will also do the corresponding action.

POP3 introduction

POP3, full name is "PostOfficeProtocol-Version3", that is, "Post Office Protocol version 3". Is a member of the TCP/IP protocol family, defined by RFC1939. This protocol is mainly used to support the remote management of e-mail on the server using the client. The POP3 protocol that provides SSL encryption is called POP3S.

The POP protocol supports "offline" mail processing. The specific process is: the mail is sent to the server, the e-mail client calls the mail client program to connect to the server, and downloads all unread e-mail. This offline access mode is a store-and-forward service that sends mail from the mail server to a personal terminal machine, usually a PC or MAC. Once the message is sent to the PC or MAC, the message on the mail server will be deleted. But most of the current POP3 mail servers can "only download mail, the server side does not delete", that is, the improved POP3 protocol.

POP3 protocol features:

Default port of POP3 protocol: 110,

POP3 protocol default transport protocol: TCP

The applicable architecture of POP3 protocol: Cramp S

Access mode of POP3 protocol: offline access

The POP3 protocol schematic is shown in the following figure.

POP3 scope of application:

POP, which is suitable for the offline model of Cramp S structure, has been developed to the third edition, called POP3. The offline model cannot be operated online, and POP does not support extended operations on server mail, which requires a more advanced IMAP4 protocol. The POP protocol is supported to use ASCII codes to transmit data messages, which can be instructions or replies.

Imap introduction

IMAP (InternetMailAccessProtocol,Internet Mail access Protocol) was formerly known as Interactive Mail access Protocol (InteracTIveMailAccessProtocol). IMAP is an email access protocol developed by Stanford University in 1986. Its main function is that the mail client (such as MSOutlookExpress) can obtain the mail information from the mail server and download the mail through this protocol. The current authoritative definition is RFC3501. The IMAP protocol runs on top of the TCP/IP protocol and uses port 143s. The main difference between it and POP3 protocol is that users can operate the mail on the server directly through the client instead of downloading all the emails.

Imap features:

Similar to POP3 protocol, IMAP (Internet message access Protocol) also provides a user-oriented mail collection service. The commonly used version is IMAP4.

IMAP4 improves the shortcomings of POP3, allowing users to browse headers to decide whether to receive, delete, and retrieve specific parts of the message, and to create or change folders or mailboxes on the server. It not only supports offline operation mode of POP3 protocol, but also supports online operation and disconnection operation. It provides users with selective function of receiving mail from mail server, server-based information processing function and shared mailbox function. IMAP4's offline mode is different from POP3 in that it does not automatically delete messages that have been checked out on the mail server, and its online mode and disconnection mode also access the mail server as a "remote file server", which is more flexible and convenient. IMAP4 supports multiple mailboxes.

These features of IMAP4 are ideal for users who operate mail between different computers or terminals (for example, you can operate the same mailbox on your mobile phone, PAD, PC mail agent), as well as those who use multiple mailboxes at the same time.

Functions of IMAP:

Compared with POP3, the method of "summary browsing" provided by IMAP greatly improves the speed of mail browsing and can effectively save customers' valuable time. This feature is very useful for users who often receive a lot of mail and want to block spam. After setting up an IMAP account, users can specify which folders are displayed and which are hidden. The summary browsing function provided by IMAP enables users to decide whether to download or not after reading the arrival time, sender, subject, size and other information of all emails. At the same time, they can also enjoy the decision of selectively downloading attachments. For example, the user receives a letter with three attachments. Users can download only one of them according to their own needs, thus saving a lot of valuable time and avoiding the passivity that the mail must be received locally before judgment can be made when using POP3 to receive mail.

The difference between pop3 and imap

The POP3 protocol allows the e-mail client to download messages from the server, but actions on the client (such as moving messages, marking read, etc.) are not fed back to the server.

IMAP provides two-way communication between webmail and the e-mail client. The operation of the client will be fed back to the server, and the mail on the server will also do the corresponding action.

Compare the following table to see the difference between IMAP and POP on the client side:

At the same time, IMAP, like POP, provides a convenient email download service that allows users to read offline. The summary browsing function provided by IMAP allows you to read all the email arrival time, subject, sender, size and other information before making a decision on whether to download or not. In addition, IMAP better supports access to new mail from many different devices at any time.

In short, IMAP brings users a more convenient and reliable experience as a whole. POP is more likely to lose messages or download the same messages multiple times, but IMAP avoids these problems through two-way synchronization between the mail client and webmail.

These are all the contents of this article entitled "what are the differences between imap and pop3". Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!

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