Everything You Need To Know About The Outgoing Mail Server.
The outgoing mail server can be alternatively referred to as the SMTP (Simple Mail Transfer Protocol), a procedure that controls the transport of emails on the Internet.
What Happens When You Send An Email?
The email delivery mechanism is actually very similar to that of the classical mailing process: an organized system is responsible for transporting your message along a series of steps that ultimately results in the deposition of the same in the recipient’s inbox. In this process, the SMTP server is simply a computer that provides SMTP service - much like an electronic postman. Once the message has been delivered to the server, it also ensures smooth delivery to the recipients.
How Does The Whole Process Work?
Basically, the trip from your computer to your receiver is performed as follows:
Let’s say that you send an email with your desktop email client or via the web from your own email address (for example email@example.com) to a certain contact (eg firstname.lastname@example.org). In computer terms, the desktop email client or webmail service is called MUA - Message User Agent.
The message is usually sent using port 25 to an SMTP server (for examplesmtp.servidor.com) which is configured in your mail client and acts as MTA - Message Transfer Agent.
The client and server then begin a brief "conversation" where the server verifies all relevant information with regards to the transmission of the message (sender, recipients, domains, etc.). Note that the language defines SMTP message transmissions only, and does not observe the content of the message body.
Then, recipient’s domain is directly connected to the server, the email is delivered immediately. Otherwise, the SMTP server delivers the message to another server that is closer to the recipient. In tech jargon, these passages are called deliveries.
What happens if the recipient's server is down or busy?
The outgoing mail server simply delivers the message to a server backup: if no authorized recipient is available. The email is then queued and the delivery process is retried periodically. If the delivery of the message is not successful even after a certain period of time, a failure notification is sent to the original sender. If there are no problems, the final segment is controlled by POP, a protocol that is responsible for collecting emails and placing it in the recipient's inbox.
A Common Issue
It should be noted that the SMTP servers that are associated with services like Hotmail, Gmail, Yahoo - are shared among many users. This means that you could end up using an IP address that has also been used by a spammer - a fact that may adversely affect the deliverability of your messages. These providers also use strict limits on the amount of emails you can send in a particular time frame. For example, Yahoo doesn’t deliver more than 100 emails per hour on any particular ID.
For this particular reason, if you plan to send out mass communications in the event of a campaign or such, it is always recommended to use a professional delivery service, which guarantees a controlled IP and avoids all these problems.