If you use any email service, then you need to know this: You cannot send or receive emails without a Simple Mail Transfer Protocol(SMTP) server. This type of server is used by many email servers and other mail transfer agents for email transmission. SMTP is sometimes combined with Internet Message Access Protocol(IMAP) and Post Office Protocol(POP), which both retrieve messages, while SMTP predominantly sends messages to a server for forwarding.

How SMTP works   

SMTP uses Transmission Control Protocol(TCP), which is a connection-oriented protocol. When the user sends an email, it goes from the originating email client to the sender’s SMTP server. When the SMTP server receives the email, it then undergoes a quick, simple process with the SMTP client to transfer the email to the receiver's email server. When the receiver’s email server gets the email, it’s then delivered to the recipient's email client through IMAP or POP3, and from there they can view it on their computer.

Benefits of using an SMTP server 

Now that we’ve shown you how email transmissions work with SMTP, we’ll explain some of the benefits of using this email protocol.

• A regular SMTP server supports both inbound and outbound email delivery. Inbound delivery is an email processing method that allows users to interact with your email server via email. Outbound delivery is an email processing method where your email server interacts with the computers of other users via email.

• Sending an email using SMTP is the simplest form of communicating through email messages. The user only needs to write an email and send it to the recipient's address. The SMTP server transmits the email to an exchange server; from there, the email is forwarded to the recipient's server.

• You can completely rely on an SMTP server in terms of outgoing emails because it always tries to resend the same email until it reaches the recipient's mailbox. Also, because it was developed from a simple platform, email messages are delivered easily and quickly—usually within a few minutes.

• Because SMTP servers are sustained locally, they can be configured exclusively to regulate important and sensitive emails. This allows users across organizations to use SMTP servers as dedicated servers for handling outgoing email messages.

• SMTP offers extended area coverage. You can send emails to people who live in different cities or countries quickly and easily from your home at a reasonably low cost.

• If you run an organization with more than 1,000 users, then you’re likely sending hundreds if not thousands of emails every day. To take full control over your incoming and outgoing emails and ensure 100% deliverability, you can switch to a commercial SMTP server that allows bulk emailing to a large audience.

Limitations of using SMTP   

While you can see that there are many benefits to using SMTP to send your email, there are a couple of limitations to the protocol as well, which we explain below.

• SMTP is an insecure service compared to other methods. It generally sends email messages without using encryption or authentication. So, there is a chance that the messages you send might be disclosed to any user. This may lead to hacking of your data.

• SMTP usually requires more back-and-forth conversation or communication between email clients and servers to deliver your sent messages. While the process usually only takes a few minutes, it relies on a complete channel of communication to complete the transfer. This can hamper the delivery of your emails to the recipients, which could cause you trouble if your email is urgent in nature.

Wrapping up   

Whether you’re a small business owner or part of an enterprise, using SMTP will allow you to scale up your email marketing because it can handle large volumes of outgoing mail. If you need the ability to engage and nurture many leads and customers, SMTP is the best method for scaling up your email communication efforts.