What Are Mail Servers? Functions and How It Works

One of the sophistication of technology is in the process of sending correspondence. In the past, it was done traditionally, requiring paper and postage. Now everything can be done electronically via email. Its fast and practical use does not end there. With new technology with one click, you can send emails to other people at the same time. It’s called a mail server, still confused? Don’t worry, in this article, we will discuss what mail servers are for you!

Table of Contents

• Definition of Mail Servers
• MailServer Functions
• MailServer component
• Mail Server Protocol
• Types of Mail Servers
• How Mail Servers Work
  • 1. First Stage (Sending Messages)
  • 2. Second Stage (Recipient Email Connected to SMTP Server)
  • 3. Third Stage (Processing Email Address)
  • 4. Fourth Stage (SMTP Sender with DNS)
  • 5. Fifth Stage (SMTP Connected Email)
  • 6. Sixth Stage (Recipient SMTP Scans Incoming Messages)
• Advantages of Mail Servers
• Closing

Definition of Mail Servers

A mail server is a server whose job is to send and receive email. Sounds easy right? But it’s more complicated than imagined where the email must go through a series of long processes before the email finally reaches the recipient. In simple terms, a mail server is an intermediary medium in the process of sending and receiving letters.

MailServer Functions

The function of the mail server is to manage the management of incoming and outgoing e-mails. This management starts by distributing email from the server to the recipient through a smooth process without any problems. This process is important considering that the contents of the e-mail contain more or less personal data from personal and corporate entities. So data leakage can be minimized properly.

It is no less important is the mail server also functions as software to install email. The goal is of course to make the email network more secure, faster, and free from various disturbances and others.

MailServer component

The mail server consists of three main components that compose it, including:

• Mail User Agents

The first component of an MUA is commonly used to compile and receive emails. This component is an application or web that you are familiar with, such as Yahoo, Gmail, Outlook, and others.

• Mail Transport Agent

The second is the MTA component whose job is to send and receive email from one computer to another. In more detail, the tasks of the MTA include: receiving e-mails, requesting mail exchange records and then including them, then choosing a good e-mail server to transfer e-mail. It doesn’t just end there, if an email fails to reach its destination, the MTA is tasked with responding automatically.

• Mail Delivery Agents

The third component is MDA which is software to deliver emails to MTA. So that occasionally the MDA task can also be performed by the MTA, namely adding a new email message to the local user’s message file.

Mail Server Protocol

Not only components, there are two main protocol categories on the mail server, namely:

• SMTP (Simple Mail Transfer Protocol), is the protocol responsible for distributing email. So it is this SMTP that communicates with the server to send local e-mail to the server. 
• IMAP (Internet message access), with this protocol, allows you to access e-mail from anywhere and anytime via the internet network. Usually, this type of protocol is often used when traveling.
• POP3 (Post Office Control ), the job is to receive e-mails and then store e-mails that have been sent until they are picked up by the destination server. However, emails on this protocol will disappear when finished reading. So it is necessary to make a backup so that it remains in your storage.

Types of Mail Servers

Below are various types of mail servers that add to your reference, namely:

• Qmail

The first type is Qmail which is known as the safest email server to use. Because this type has almost no weaknesses that are at risk of attacking the security system. Providers that use the Qmail service include Yahoo and Hotmail.

• Sendmail

This second type is standard for Linux but can support any operating system. Its good performance and easy settings make sendmail also widely used by users. However, from a security point of view, many improvements must be made first.

• Postfix

Development of sendmail where postfix can be not only operate on Linux but also on Mac OS X. When compared in terms of security, Postfix is ​​better and more secure than sendmail.

How Mail Servers Work

As mentioned above, the main way of working on the mail server is to send and receive emails. This article will explain the five stages in detail about how it works.

1. First Stage (Sending Messages)

The user creates a message that will be addressed to the recipient by clicking send. Furthermore, it becomes the task of the MUA who sends the email. The recipient’s email is automatically connected to your domain’s SMTP.

2. Second Stage (Recipient Email Connected to SMTP Server)

Then the recipient’s email communicates with the MTA server via SMTP. It is in this section that the user’s email address, the recipient’s email address, the contents of the message, and its attachments are given.

3. Third Stage (Processing Email Address)

After that, at this stage, the MDA component through SMTP processes only its domain-specific recipient address. If the domain name is the same then it will be redirected to the POP3 server. If the domain name is different, the SMTP server communicates first with the domain server.

4. Fourth Stage (SMTP Sender with DNS)

The MTA communicates with DNS to obtain the receiving server. After that, DNS takes the recipient’s domain email name, then translates it into an IP address. After knowing the IP address, the mail server works more efficiently than before.

5. Fifth Stage (SMTP Connected Email)

The recipient’s IP address is known, the next step is that the email is forwarded by MDA to the SMTP server before finally arriving at the destination.

6. Sixth Stage (Recipient SMTP Scans Incoming Messages)

In this last stage, the MUA immediately moves incoming messages. If the domain name is recognized then the message is forwarded to the IMAP or POP3 domain. Next, the message is placed on the sendmail queue.

Advantages of Mail Servers

Just like other providers, mail servers also have advantages, including:

• Faster

The first advantage of the mail server is that this service is proven to be faster. Why is that? Because basically, you can set up a mail server freely in terms of email distribution, thus making your email reach the recipient faster and more efficiently use of time.

• Protected Privacy

Usually, email can only be accessed using the internet network. This is a factor of privacy and your data is well protected because not everyone can access it, only internal parties.

• Can Overcome Damage

The mail server assists with troubleshooting errors that occur to users when sending or storing emails. This assistance can be easily and quickly obtained without having to wait a long time.

• Can Create Business Emails For Members 

Finally, the mail server provides additional domain names for each member of the business team. You can use this if you choose a paid email service. The goal is to make the email look more professional and gain the trust of customers.

Closing

Thus an explanation of the Mail server. In short, this technology greatly facilitates the distribution of sending and receiving e-mails. In addition, the process is guaranteed to have no problems and run smoothly. If you look at how it works, it turns out to be quite complex with various stages that must be passed first.

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