What email protocol is smtp?

smtp is an email protocol. It is a set of specifications for transmitting emails from a source address to a destination address. It controls the way emails are transferred. The SMTP server is a sending email server that follows the SMTP protocol.

Commonly used email protocols include SMTP, POP3, and IMAP4. They all belong to the TCP/IP protocol family. By default, they are sent through TCP ports 25, 110 and 143 establish a connection.

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SMTP introduction:

The full name of SMTP is "Simple Mail Transfer Protocol", that is, simple mail Transfer Protocol. It is a set of specifications for transmitting mail from a source address to a destination address, which controls how the mail is transferred. The SMTP protocol belongs to the TCP/IP protocol suite and helps each computer find the next destination when sending or relaying letters. The SMTP server is a sending email server that follows the SMTP protocol.

SMTP authentication, simply put, requires that you must provide an account name and password before you can log in to the SMTP server, which leaves no opportunity for those who spread spam. The purpose of adding SMTP authentication is to protect users from spam.

SMTP has become the de facto standard for E-Mail transmission.

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