SMTP is the core protocol used for sending email and transferring messages between mail servers. When you click Send in an email application, the message is normally submitted to a mail server through SMTP.<\/p>\n
SMTP accepts a message from the sender and attempts to deliver it to the destination mail server. Incoming email is normally accessed through protocols such as IMAP or POP3.<\/p>\n
An SMTP server receives outgoing messages, performs required checks and attempts delivery to the recipient’s mail system.<\/p>\n
Business email systems normally require users to authenticate before sending mail. This helps prevent unauthorized people from using the server to send spam.<\/p>\n
TLS helps encrypt communication between an email client and the SMTP server. Secure connections are particularly important when account credentials are transmitted.<\/p>\n
A successful SMTP submission does not guarantee inbox delivery. Domain reputation, IP reputation, SPF, DKIM, DMARC and message content can all influence deliverability.<\/p>\n