SMTP Simple Mail Transfer Protocol

[mehadihasan123456]

SMTP, POP3, IMAP protocols

SMTP ( Simple Mail Transfer Protocol ) is a mail transfer protocol used to send email between mail servers. It provides a standardized way to transmit email messages over a network.

SMTP works on the following principle:

Establishing a connection: When a sender sends a message, their iran email list email client (such as Outlook or Thunderbird) establishes a connection to the sender's email server on a specific port (usually port 25).
Greeting. The sender's mail server greets the connection with the "220" command and provides information about itself, such as the server name or a greeting message.
Authentication. If required, the sender's mail server may request authentication of the sender to ensure that he or she is authorized to send the message from the specified address. Typically, a password or other authentication method is used.
Sending a command and an addressed letter. The mail client sends a "MAIL FROM" command to specify the sender of the letter, and then a "RCPT TO" command to specify the recipient. Each recipient is specified by a separate "RCPT TO" command.
Sending a message. After specifying the sender and recipient, the mail client sends the message itself using the "DATA" command. The contents of the message, including headers and message text, are transmitted to the mail server.
Server response and message transmission. The sender's mail server receives the message, checks it for errors or invalid content, and then transmits it to the recipient's mail server. If the message is successfully transmitted, the sender's server responds with a "250 OK" response.
Terminating the connection. After the letter has been successfully transmitted, the sender's mail server terminates the connection using the "QUIT" command.
SMTP is the standard for sending email, and it provides reliable and efficient transmission of emails between mail servers. SMTP also supports authentication, encryption, and other advanced features to ensure safe and secure delivery of email.