Information Technology Reference
In-Depth Information
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message 1
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message 2
message 3
Note again the Message-Id and In-Reply-To parameters, as well as the new
References parameter. The In-Reply-To parameter is message ID of the pre-
cedingmessage,buttheReferencesparameterincludesallthemessagesinthis
exchange (also called a Thread), starting with the original. Just to be different,
the Subject line was changed by the sender instead of using the default con-
vention. And note that in the message body the previous message is quoted at
levelone,whiletheoriginalmessagethathasmadethreetripsnowisquotedat
level two. The References parameter helps mail clients sort how message
threadsaredisplayed.Eventhoughthesubjectlinewaschanged,theclientcan
use the message IDs in the reference field to group all messages in the thread
together.
Mail clients and servers
E-mailismanagedwithane-mailclient,whichmaybeanapplicationinstalled
locally on the computer, or it may be web-based, in which case it is accessed
through a web browser. Some advantages of an installed mail application are
the ability to copy messages to a local store, and to access them offline, which
isusefulwhenthereisaneedtoanalyzealargequantityofmessagesandsome-
what more sophisticated user interfaces. The main advantage of web-based
clients is that your mail can be accessed from any computer with a web
browser. Web-based email comes in two forms. Your organization's mail
server may provide a web page which accesses mail on its servers. The other
alternative is an independent mail provider such as Yahoo!, Google or MSN.
The mail on these sites will be completely separate from your organization.
Inaweb-basedclient,thestorageandaccessofmailishandledentirelybythe
remotemailserverandiscompletelyhiddenfromtheuser.Locallyinstalledmail
clientapplicationsneedtobeabletoaccessamailboxormailstore.Ifthelocal
computerisamailserver,thenthemailstoremaybeonthelocalfilesystem,but,
much more likely, the mail client is used to access a mail store on separate mail
server. The mail client needs to be set up with the correct connection parame-
ters to the mail server. There are a few different protocols for communication
between mail clients and mail servers, among them POP and IMAP, which are
internetstandards,andMAPI,whichisaMicrosoftprotocol.Thechoiceofmail
applications depends to some extent on what computer platform you are using
