Intoduction: Multi Tear Architecture

Hi Brothers, This is so important specially for graduate students.......

First, What Multi-tear architecure means?N-tier (multi-tier) applications have become the normal for building enterprise software today. To most people, an N-tier application is anything that is divided into discrete logical parts. The most common choice is a three-part breakdown—presentation, business logic, and data—although other possibilities exist. N-tier applications first emerged as a way of solving some of the problems associated with traditional client/server applications, but with the arrival of the Web, this architecture has come to dominate new development. This will help u alot for designing application.


Then
What is the goal of Buidling such architecture?
1- Maintainability.
2- Security.
3- availability.
and so on.

The most common N-Tier is a 3 tear, as following:

Let's Descripe Each Component:
- Application Data: Which is our database of enterprise system.
- Data Access Logic Component: which handle all database operations like Create, Read , Update, Delete; CRUD is a standard behavior for all DB operations..
- Business Entities: Is an important component for representing all entities, ummm, such as order, products in an ordering system.
- Business Process Component: Handles all business process during system, like calculating total cost of order, get the balance of one customer, and so on.
- Presentation: Handle all user activies through user friendly interface, presentation may be desktop, web, or mobile.....

That is enough now, this is a start to multi-tier...
Later I will discuss how to represent each tier or layer seperatly, and how to imeplement it...

I wish This post help u, Waiting for ur comments