What is a Mail Server?

With the click of a mouse button, you can send an email from one point of the globe to another in a matter of seconds. Most of us take this process for granted, giving little thought to how it actually works. It’s easy to understand how standard snail mail gets from point A to point B – but how does an email message make its way from a sender to a recipient? The answer to that question revolves around something called a mail server.

What is a Mail Server?

A mail server (sometimes called an email server) is a software program that sends and receives email. Often, it is used as a blanket term for both mail transfer agents (MTA) and mail delivery agents (MDA), each of which performs a slightly different function.

Mail servers play a crucial role in the email delivery process. Without them, users would have no way of transferring those messages to and from other mail clients.

How does it work?

A mail server facilitates the sending and receiving of emails using a series of well-defined steps and protocols. Here’s how it typically works:

Sending an Email

• Compose. The process begins when a user composes an email using an email client. This client can be either a web-based interface or a desktop application.
• Connect to server. Once the email is ready to be sent, the email client connects to the email server using the Simple Mail Transfer Protocol (SMTP). The client submits the email along with the recipient’s address to the server.
• Authentication. The server then verifies the sender’s credentials (username and password) to authenticate the request. This step ensures that the sender is permitted to use the server for email transmission.
• Lookup and routing. Next, the server looks up the domain of the recipient’s email address in the Domain Name System (DNS) to find the corresponding recipient server. Once identified, it forwards the email to the recipient’s email server.

Receiving an Email

• Receipt by recipient’s server. The recipient’s mail server receives the message and processes it. This server also uses SMTP to receive messages but employs additional protocols like Post Office Protocol version 3 (POP3) or Internet Message Access Protocol (IMAP) for email retrieval by the client.
• Storage. Upon receipt, the email is stored in a mailbox on the recipient’s server until the recipient accesses it.
• Access by recipient. When the recipient opens their email client, the client contacts the server to download new mail. If using IMAP, the email can be viewed directly on the server, allowing synchronization across multiple devices. With POP3, emails are typically downloaded and possibly removed from the server, depending on the client’s settings.

Additional Functions

• Spam and security filters. As emails are processed, both incoming and outgoing messages are checked by the server for spam and malicious content, using various filters and scanning software to protect users.
• Backups and archives. Mail servers often include functionality to backup and archive emails, ensuring data integrity and compliance with data retention policies.

What is the purpose of a Mail Server?

At its simplest, a mail server collects and distributes emails to their intended destination. You can think of it as a computer that acts as an electronic post office for email, which allows you to control the transfer of emails within a network through different protocols.

A mail server can also encrypt the transfer of emails, so nobody can gain access to the information in your personal email inbox. Today’s mailboxes can include a treasure trove of sensitive information from social media details to financial data that hackers are eager to sell. So it’s more important than ever to secure your emails. To do just that, some mail servers and server software can also provide additional security features to guard against cyber security attacks.

Whether you’re checking your emails from your phone, at work, on the web, or by using a software solution, your email is handled by both incoming and outgoing mail servers. Without this well-oiled machine of protocols and server software, you wouldn’t receive all of your important messages or time-sensitive emails. Additionally, problems with your incoming mail server may present challenges for your emails coming in on time or at all.

Benefits of using a Mail Server

• Efficient Email Communication: A mail server streamlines email communication by efficiently managing the flow of messages. It ensures reliable delivery of emails, reducing the chances of lost or undelivered messages. With a mail server, businesses can have a centralized system for sending, receiving, and storing emails, allowing for easy access and management of email correspondence.
• Enhanced Security and Privacy: By using a mail server, businesses can enhance the security and privacy of their email communication. Mail servers often incorporate advanced security measures, such as encryption and spam filtering, to protect against unauthorized access and ensure the confidentiality of sensitive information. Additionally, hosting emails on a private mail server gives businesses more control over their data and reduces the reliance on third-party email providers.
• Customization and Branding: Mail servers offer the flexibility to customize email configurations and settings to align with the specific needs of a business. This includes setting up personalized email addresses with the business domain name (e.g., [name]@yourcompany.com), creating email aliases, and implementing custom email routing rules. Such customization options enable businesses to establish a professional email presence and reinforce branding in all email communications.
• Scalability and Control: A mail server provides businesses greater scalability and control over their email infrastructure. Organizations can tailor the server’s performance and storage capabilities to meet their requirements, ensuring reliable email delivery even as the business grows. Control over the mail server also allows businesses to implement advanced features and integrations, such as email archiving or CRM integration, to streamline internal processes and enhance productivity.
• Compliance and Regulatory Requirements: Certain industries, such as healthcare or finance, have specific compliance and regulatory requirements for handling sensitive data through email. Using a mail server enables businesses to implement the necessary security measures and meet industry-specific regulations, such as HIPAA or GDPR. Compliance with these standards helps businesses avoid legal complications and maintain the trust of their clients and partners.

Types of Mail Servers

Mail servers can be broken down into two main categories: outgoing mail servers and incoming mail servers. Outgoing mail servers are known as SMTP, or Simple Mail Transfer Protocol, servers. Incoming mail servers come in two main varieties. POP3, or Post Office Protocol, version 3, servers are best known for storing sent and received messages on PCs’ local hard drives. IMAP, or Internet Message Access Protocol, servers always store copies of messages on servers. Most POP3 servers can store messages on servers, too, which is a lot more convenient.

Considerations for choosing a Mail Server

An organization must take the following into account before choosing a mail server:

• Security. Email services should use advanced tools to protect information. Other features an email provider may provide include encryption, antimalware, spam filtering, and data loss prevention tools.
• Cost. On-premises email servers cost more upfront but also provide more fine-grained control over systems and security. Cloud-based email services typically have less upfront cost and require less maintenance.
• Archiving and storage. Ensure a vendor offers sufficient storage for email archiving. Some services may also offer an option to move old messages to an archive automatically.
• Compatibility. Email services may also offer options to sync with web-based and mobile applications, such as email, calendar, and contact applications.

Conclusion

Mail servers are specifically designed to offer a more secure and optimized environment in which online communication is faster, encrypted, and uninterrupted.

To choose the right electronic mail server for your business, you need to look for one that will offer support for all communication services, advanced security tools, archiving capabilities, and other features that will satisfy your needs.