Week 3 Lab Overview:
Set up a sendmail server on the Linux system. I also sent a message to my own username and made sure that the mail was sent correctly.
Electronic mail has become an integral part of our daily lives. The architecture behind electronic mail is similar to the postal system. Email is address similar with to and from addresses and is dropped off at an outgoing mail server. Mail is then transferred from one server to another server. This week, we will set up our own post office to accept e-mail address and transfer them to other post offices to deliver them to a local user's mailbox. Two commonly used e-mail server apps on Linux are Sendmail and Postfix. Both of these server applications are actually comprised of smaller programs that each perform specific tasks. We will also look at many different protocols and approaches to set up an e-mail architecture, with separate incoming and outgoing mail servers and clients that are applications themselves or web-based clients.
The following are two types of e-mail servers:
Outgoing Mail Server: Using the simple mail transfer protocol (SMTP), this server type receives e-mail messages from an e-mail client application or another server. This server forwards the message to the server of the recipient's domain or, if the recipient is part of the same domain, forwards it to the incoming mail server for the domain. The outgoing mail server is referred to as the mail transfer agent (MTA). Two common outgoing mail servers for Linux are Sendmail and Postfix.
Incoming Mail Server: The incoming mail server receives e-mail from the local outgoing mail server and stores it in a local directory the user can access when his or her mail client connects to this server. When a client connects to an incoming mail server, either the post office protocol version 3 (POP3) or Internet message access protocol (IMAP) is used. The incoming mail server is referred to as the mail delivery agent (MDA). If a system is using Sendmail as the outgoing mail server, the MDA is the program procmail.
SMTP - protocol. To send e-mail
MUA - e-mail client application i.e. Thunderbird
MDA - Connect to this server to receive mail
MIME is the format used to send attachments with mail
IMAP is the protocol mail clients use to synchronize their mail with the server.
MTA is another way to refer to the outgoing mail server.
POP3 is the protocol used by clients to move a copy of a. mail message to their computers.