Few decades before, all of them use to send the messages in the form of letters after the improvement of technology and the usage of internet made this job simpler by introducing email service. The email is a form of electronic message which is sent from sender to receiver immediately. The email is highly used in the business places also it is used for personal needs as well. Sending an email seems to be like a magic as the electronic message you have sent to the receiver will be delivered correctly within a short span of time but this simple thing happen by involving on many process.

The email has been send from the sender to the receiver correctly can be achieved only with the assistance of SMTP server which plays a predominant role in the process of sending mail. Simple Mail Transfer Protocol (SMTP) server which acts moreover like a postman in the process of sending email as it takes the complete work of delivering the email on the respective address perfectly.

  • SMTP server is a server or collection of servers which is responsible for the entire process of email delivery.
  • The SMTP servers have their own address or set of addresses which has been set by the client using the server.
  • SMTP servers of the common providers were shared among the users as they are based on non-dedicated IP’s. While the common provider’s sets certain limits on sending the email.
  • In case of sending a mass mail then it is better to have an own SMTP server so that can have own dedicated address and can set free of limitations.

What the SMTP server will do while sending email?

The mail that has been send by the sender from their mail client to the declared recipient usually sent through Port 25 to the SMTP server which has its own address. Then the SMTP server acts as a Message Transferring Agent (MTA) and it is been set then it will given to its mail client. After that the mail client and SMTP server transmit the information of the email completely and then the SMTP server checks the flow of the data transmission which includes sender, receiver, domains, etc. This server will not deal with the body of the email as they will not check the message content.

The mail will be delivered to the recipient immediately if their domain is directly connected to the SMTP server. If the recipient domain doesn’t connect the SMTP server directly then the SMTP server broadcast the mail to the incoming server that is close to the recipient. Further the process will be continued as same until the recipient’s domain is connected directly and the mail get delivered once they are connected successfully. In case if the recipient server is down or busy the SMTP server will store the message in the backup server and process them. There is no backup server then the message will be queued in the SMTP server and processed until the message getting delivered successfully.