Computer Network Basics Questions Medium
SMTP (Simple Mail Transfer Protocol) is a standard protocol used for sending and receiving email messages over a computer network. It is responsible for the transmission of email messages from the sender's mail server to the recipient's mail server. SMTP operates on the application layer of the TCP/IP protocol suite and uses a client-server architecture.
SMTP works by establishing a connection between the sender's mail server and the recipient's mail server. The sender's mail server initiates the connection and sends the email message to the recipient's mail server. The recipient's mail server then stores the email in the recipient's mailbox until it is retrieved by the recipient.
SMTP uses a set of commands and responses to facilitate the transfer of email messages. These commands include HELO (used to identify the sender's mail server), MAIL FROM (specifying the sender's email address), RCPT TO (specifying the recipient's email address), DATA (beginning the transmission of the email message), and QUIT (ending the SMTP session).
SMTP is a reliable and widely used protocol for email communication. It allows for the efficient and secure transfer of email messages across different mail servers and networks. However, SMTP is primarily concerned with the transfer of email and does not provide mechanisms for email retrieval or storage, which are handled by other protocols such as POP (Post Office Protocol) or IMAP (Internet Message Access Protocol).