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Understanding Windows Vista: HTTP, SMTP, POP3, and IMAP Protocols

written by: Ashwin Satyanarayana•edited by: Christian Cawley•updated: 5/11/2009

Do you email? Of course you do. But then, do you which protocol your email uses? Which protocol do you think the email that you check off your free gmail, hotmail or yahoo account would follow? What about MS Outlook? Read on to know more about the various email protocols:

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    The E-mail setting consists of a lot of acronyms, and they are: HTTP, POP3, SMTP, IMAP, among others. What does it mean and how much should the user worry about it? Usually there won’t be any choice of server types in the system. The ISP will hold up for either IMAP or POP3 for the incoming mail, and for the outgoing mail it will use SMTP. The meaning of these terms is given below.

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    HTTP Protocol

    The Hypertext Transfer Protocol in short is known as HTTP. The HTTP is the protocol that is used when you connect to a website over the internet. Its cousin, HTTPS (HTTP Secure) is used for websites or web pages that utilize enhanced security.

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    SMTP Protocol

    The Simple Mail Transfer Protocol in short is known as SMTP. For sending the e-mails, we use the SMTP protocol. It is a division of the TCP/IP protocol suite, which is used to run the Internet.

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    POP3 Protocol

    The Post Office Protocol in short is known as POP3, which is used as a garden variety or common internet mail service protocol for passing and storing in the mail box. The POP3 protocol is widely used because it works well, but it doesn’t contain the more advanced features of the IMAP protocol. The main limitations of POP3 protocol is that, when you want to check email, you’ll have to download the entire message waiting for the user. All the message copies can be left on the server. Several e-mail programs, however, work smarter now and they would download only the part of the message that hasn’t been downloaded yet. The SMTP protocol is use by POP3 to move the message from one processor to another and then to the client.

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    IMAP Protocol

    Internet Mail Access Protocol in short is known as IMAP protocol. The IMAP protocol is the newest protocol which has more features than POP3 protocol. It provides a strong verification and will support Kerberos security. From the standard user’s view, IMAP protocol's main advantage is that it’s smart enough to permit the user to manage his mail on the server. Only the message header can be downloaded so that you can decide what to download from the message or you can also delete the message from the server without reading it. Using the IMAP protocol, we can shuttle the message between the folders. These capabilities of the IMAP protocol make it useful for checking mails from many computers.