The flow of emails from the sender to the recipient undergoes a certain process which can be likened to the process of sending mails through a traditional postmaster. When you send a mail via the post, certain processes are undergone –including the necessary registration and eventual delivery– before the mail gets to the recipient. The same thing happens when an email is sent out by a sender. The procedure which the internet emails undergo before they get to the email inbox of the recipient is known as simple mail transfer protocol which is normally abbreviated as a SMTP Server. The SMTP server is an essential aspect of this process. It performs the function of a postmaster who in the traditional mail sending process handles mail delivery. It is a computer running SMTP that receives emails from the senders and delivers them to the recipients. You can buy SMTP server at authority providers on th web.
Email sending process via SMTP Server
Normally before you send an email, you need to have an email address with an email service provider such as Google, Yahoo and others. It is through this email ID that you will be able to send email to another person that owns an email address. When you compose your emails and click on the send button in order to deliver it to a particular recipient with your mail client or webmail (this is in technical language called message user agent), they normally leave you email compose box via port 25. But they are not delivered immediately to the recipients.
It hits the SMTP server assigned to your message user agent when you set up an email address. The SMTP performs the function of MTA (message transfer agent). A short conversation is initiated between your client and the server. In this process, all the data concerning the transfer or delivery of the message such as the domain, the recipient and sender will be verified by the SMTP server. Bear in mind that the content of the message is not defined by SMTP. It only defines the transmission of the message.
The email will be delivered quickly if there is a direct connection with the server and the domain where the recipient account is domiciled. When no such connection exists, the email will be pushed to the incoming server nearer to the recipient by the SMTP. In situation where the server of the recipient is busy or experiencing downtime, the message will be delivered to a backup server by the SMTP host. When there is no backup server, the email will be queued to be resent at a regular intervals. If no success is recorded after this, the email will be sent back to the sender as failed delivery.
When everything goes smoothly without any hitches, the last stage of email delivery is handled by another protocol known as POP. It is the function of the POP to receive the email from the SMTP server and delivers it directly to the inbox of the recipient.