client_server_intro.html

this gives an introduction to microsoft dna.

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Java (Parts 1 and 2) in Slovak</A><BR>
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Introduction to Microsoft DNA
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Client Server Model Applications
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As technology advanced, connecting machines and sharing 
data became an important goal and a pressing reality for 
application developers. 

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Simple networks formed and new 
applications and application architectures arose. Since 
networking and resource sharing introduced larger and more 
complex problems into the development environment, and because
the inherent flaws in monolithic applications were becoming
clear, a new 
approach that captured the nature of these new applications 
was devised.  And because the "applications" had grown, so 
had the stages of an application from an abstract viewpoint.

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Client-Server applications became all the rage. And the 
monolithic applications started to fade into the past like 
some forgotten dinosaurs.

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In the client-server model, applications were broken apart,
distributing processing between client computers 
and server computers.

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As client-server applications became feasible, so too 
did the layering of the technology become more important. 
In the client server model, the three layers of an 
application could more easily be isolated.  In fact, 
such isolation became even more crucial as scalability, 
distribution and mainenance became even more complex.

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Another factor in the separation of the layers came 
from the data.  As sharing data became essential to 
faster and wider information distribution, the network 
systems drove applications to evolve into data sharers. 

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Rather than store data locally, in a client-server application,
data would be stored in a central repository where it could 
be accessed by multiple clients who wished to "share" it.

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The benefit of this architecture was that it gave access 
to large numbers of users so that they could store and 
retrieve important data in a consistent and stable manner 
generally from a "fully loaded" application on the client 
machine. Order processing, accounts, internal systems; email 
and database applications became the norm in the 
client-server era. 

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The traditional client server applications enabled, and 
encouraged, developers to build feature rich solutions 
that integrated key technologies in a single point of 
access. 

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Typically a developer would focus on delivery of the 
graphical user interface and storing data in repositories 
that enabled users to share data. Technologies like ODBC 
(Open Database Connectivity), Visual Basic, Visual C and 
MFC (Microsoft Foundation Classes) helped developers 
build applications in short timescales that could access 
and share data. 

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