For personal applications, email servers such as those hosted by Yahoo, Gmail, and others offer all of the features that you will ever need. For business applications, though, such as email marketing campaigns, using your own SMTP server is ideal for a number of reasons.
In this article, we’ll explore what SMTP servers are, how they work, and the benefits that they offer for organisational use.
What is an SMTP Server?
SMTP is an acronym that stands for “simple mail transfer protocol”. In the simplest possible terms, an SMTP server is a server or collection of servers whose sole purpose is to send and receive messages in the form of emails. From a technical standpoint, an SMTP server is built just like any other server – it’s the function of an SMTP server that sets it apart. SMTP servers will also have their own dedicated address or set of addresses that will be determined by the client using the server.
How an Email Goes from the Sender to the Receiver
Compared to many advances of the digital age, sending and receiving an email may seem like a fairly basic process. However, there’s still a lot that goes on when you hit “send”. The process for how an email goes from the sender to the receiver is as follows:
You compose and send an email using your mail client from your address (i.e. firstname.lastname@example.org) to the address of the email recipient (i.e. email@example.com).
Once you hit “send”, the email is sent via port 25 to an SMTP server, which has its own address (i.e. mail.websitename.com).
This SMTP server acts as a Message Transfer Agent (MTA) and is given to your mail client when you set it up. The mail client and the SMTP server relay information regarding your email back and forth, with the SMTP server checking the transmission data of the email such as its sender, its recipient, the domains of each, and so on. However, the SMTP server does not check the body content of the email.
If the recipient of your email has an account where the domain is directly connected to the SMTP server then the email is delivered right away. If they do not have an account where the domain is directly connected to the SMTP server then the SMTP server relays the message to an incoming server that is closer to the recipient. This process continues until the message is delivered to a server that is connected directly to the recipient’s domain, at which point the email is delivered.
If the recipient’s server is down or busy then the SMTP server simply stores the message in a backup server. If no backup server is available then the message is queued and the SMTP server will attempt to redeliver it periodically until a successful delivery is accomplished. After a certain number of unsuccessful delivery attempts, though, the message is returned to the sender and the sender is notified that it was not successfully delivered.
Benefits of Using Your Own SMTP Server
SMTP servers employed by Gmail, Yahoo, and others are shared among users. In most cases this is a fine solution, but when sending out mass emails it can be a problem. For one, you may end up using an IP address to deliver your messages that is also used by a spammer, which can cause them to not be delivered correctly. You may also not be able to send as many emails as you would like since email service providers often impose strict limits on the number of emails that can be sent out in a given time period. Yahoo, for example, lets you send out no more than 100 emails an hour. By setting up your own SMTP server, though, these issues are avoided since you will have your own dedicated IP address for your private use as well as no limits on the number of emails that you can send out.