Introduction to Mail Services POP3, SMTP and IMAP

The essence of the mail service is several background services for sending and receiving mail. This article introduces the related content of POP3, SMTP and IMAP.

POP3

POP3 is the abbreviation of Post Office Protocol 3, the third version of the Post Office Protocol, which specifies how to connect personal computers to Internet mail servers and download electronicElectronic agreement for mail.It is the first offline protocol standard for Internet e-mail. POP3 allows users to store e-mails from the server to the local host (ie their own computer), and delete the e-mails stored on the mail server, while the POP3 server follows POP3The incoming mail server of the protocol, used to receive email.

IMAP

IMAP stands for Internet Mail Access Protocol, the Interactive Mail Access Protocol, which is one of the similar to POP3 mail access standard protocols.one.The difference is that after IMAP is turned on, the emails you receive in the email client still remain on the server, and the operations on the client will be fed back to the server, such as: delete emails, markIf it has been read, etc., the mail on the server will also act accordingly.Therefore, whether you log in to the mailbox from the browser or log in to the mailbox from the client software, the emails and statuses you see are the same.

SMTP

SMTP stands for Simple Mail Transfer Protocol, the Simple Mail Transfer Protocol.It is a set of specifications for transferring mail from a source address to a destination address, and it controls how mail is relayed.The SMTP protocol belongs to the TCP/IP protocol family, which helps each computer find the next destination when sending or relaying a letter.An SMTP server is an outgoing mail server that follows the SMTP protocol.Sending mail generally uses the SMTP service.

• SMTP authentication, in short, requires that you have to provide an account name and password before you can log in to the SMTP server, which makes it impossible for spammers to take advantage.
• The purpose of adding SMTP authentication is to protect users from spam.

Service common port number

• The default port numbers and common addresses of related services are as follows:

References

• http://help.163.com/09/1223/14/5R7P6CJ600753VB8.html