While setting up a new website you probably want to set up a mail server to handle the incoming and outgoing emails. A mail server is a complex system that consists of various software components each component provides a specific function. You can set up your own mail server or can use paid service.
In this article, we will discuss the components used to set up the mail server on a Linux system.
Mail service components
A mail server usually consists of the given components –
- Mail User Agent
- Mail Transfer Agent
- Mail Delivery Agent
- IMAP and/or POP3 server
Ahead we will discuss each component required to set up a mail server in detail.
Mail User Agent
The email component that a user can see and interact with is called a mail user agent or MUA. Examples of MUA are a thunderbird mail client, Microsoft Outlook, etc. It allows a user to read and compose emails on a system.
Mail Transfer Agent
The mail transfer agent (MTA) is a software program that handles the SMTP (Simple Mail Transfer Protocol) traffic. The responsibility of MTA is to send mail from users to external MTA and receive mail from external MTA.
Some examples of MTA softwares are postfix, Exim, Sendmail.
Mail Delivery Agent
A mail delivery agent (MDA) also known as a local delivery agent (LDA) retrieves emails from a mail transfer agent and places them in the inbox at the appropriate address.
Examples of mail delivery agents are postfix-maildrop, dovecot, and Procmail.
IMAP and/or POP3 server
IMAP (Internet Message Access Protocol) and POP3(Post Office Protocol) are the protocols used by mail clients. IMAP allows multiple clients to connect to an individual mailbox simultaneously. Clients generally leave messages on the server until the user explicitly deletes them.
POP3 (Post Office Protocol) is a simpler protocol that downloads the email and deletes it from the server. IMAP is recommended for receiving emails if you are working across multiple devices. POP3 is recommended if you prefer to have all the emails accessible offline.
Examples of softwares that can provide IMAP and/or POP3 server functionality are Dovecot, Zimbra, Courier, etc.
Mail server additional component
The additional mail components can be useful in some way. For example, an antivirus program can be used to scan mail for potentially harmful messages or attachments. So that a user can be protected from an external threat.
You might want the following additional program to configure with your mail server.
- Spam filter
The spam filter is a program that is used to detect unwanted mails and prevents those mails from getting to a user’s mailbox. The program finds spam mails on the basis of certain criteria defined to the program.
This filter can also be applied to outgoing mails. SpamAssassin is a popular open-source spam filter program.
As discussed earlier antivirus program is used to detect viruses, trojans, malware, and such other threats in incoming and outgoing emails. There are various antivirus programs available. ClamAV is an example of a popular antivirus engine.
Webmail is a mail client that can be accessed using a web browser. Gmail is a well-known example of this. Examples of a webmail program are Roundcube and Citadel.
Before setting up your mail server you should have an understanding of these terms. Now if you have a query then write us in the comments below.