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TCP / IP messages

E-mail is one of the most important applications of TCP / IP.


You will not be used ...

When you write a message, you will not be using TCP / IP.

When you write a message, you use the e-mail programs, such as Lotus Software Notes, Microsoft produced the Outlook, or Netscape Communicator, and so on.


Mail program will be used ...

Your e-mail program uses a different TCP / IP protocol:

  • Use SMTP to send mail
  • Use POP to download mail from the mail server
  • Use IMAP to connect to the mail server

SMTP - Simple Mail Transfer Protocol

SMTP protocol for transmitting e-mail. SMTP is responsible for sending messages to another computer.

Under normal circumstances, the message will be sent to a mail server (SMTP server), then sent to another (or several) server, and then eventually sent to its destination.

SMTP can also be transferred in plain text, but can not transmit binary data such as pictures, sounds or movies and the like.

SMTP uses the MIME protocol to send binary data over TCP / IP networks. MIME protocol binary data will be converted to plain text.


POP - Post Office Protocol

POP protocol is used to retrieve the mail server mail program above message.

If your mail program uses POP, then once it is connected to the mail server, all your messages will be downloaded to your mail program (or called mail client).


IMAP - Internet Message Access Protocol

Similar to POP, IMAP e-mail protocol used by the same program.

The main difference between the IMAP protocol and the POP protocol is: If even on IMAP mail server, it does not automatically download mail to into the mail program.

IMAP allows you the ability to view messages before downloading them through the mail server. Through IMAP, you can choose to download messages or just delete them. For example, when you need to access the mail server from different locations, but only want to return to the office to download e-mail, IMAP in this case it would be useful.