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3 tier architecture application or MVC application are different or same

Answer :-
http://en.wikipedia.org/wiki/Multitier_architecture#Comparison_with_the_MVC_architecture
Comparison with the MVC architecture

At first glance, the three tiers may seem similar to the model-view-controller (MVC) concept; however, topologically they are different. A fundamental rule in a three tier architecture is the client tier never communicates directly with the data tier; in a three-tier model all communication must pass through the middle tier. Conceptually the three-tier architecture is linear. However, the MVC architecture is triangular: the view sends updates to the controller, the controller updates the model, and the view gets updated directly from the model.

From a historical perspective the three-tier architecture concept emerged in the 1990s from observations of distributed systems (e.g., web applications) where the client, middle ware and data tiers ran on physically separate platforms. Whereas MVC comes from the previous decade (by work at Xerox PARC in the late 1970s and early 1980s) and is based on observations of applications that ran on a single graphical workstation; MVC was applied to distributed applications later in its history (see Model 2).

Today, MVC and similar MVP are Separation of Concerns design patterns that apply exclusively to the presentation layer of a larger system. In simple scenarios MVC may represent the primary design of a system, reaching directly into the database; however, in most scenarios the C (Controller) and M (Model) in MVC have a loose dependency on either a Service or Data layer/tier.

Question:-
Whats difference?

Answer:-
3 teir is a form of theoritical side .
while MVC is implemented practically. just like a layered architure and its implementation can be OSI & TCP-IP model.

They both are divided into 3 parts but difference comes in communication between 3 layers . If communication is of the linear form
or trinagular form that is diffrent. In a MVC model ther can be 2 commuincations,

1) View calling controller ; controller calling model & vice versa
2) View calling controller; controller calling model & model in turn updating view.

So,important difference would be 3 tier is theoretical, while MVC is practical.

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