3 Tier Architecture

3 Tier Model contains following layers

1) Application Layer

2) Business Layer(Property Layer(Sub layer of Business Layer))

3) Data Layer

* Application layer is a from where we design using controls like textbox,labels and command buttons etc.

* Business layer is class where we write the functions which get the data from application layer and passes through the data access layer.

* Data layer is also the class which gets the data from business layer and sends it to the database or gets the data from database and sends it to the business layer.

* Property layer is the sub layer of business layer in which we make the properties to set or get the values from the application layer.These properties help to sustain  the value in an object so that we can get these values  till the object destroy.

Data Tier

This tier is responsible for retrieving;storing and updating from information therefore this tier can be ideally represented through a commercial database.Usage of stored procedures increases the performance and code transparency of an application.

Logical Tier

This is the brain of 3 Tier Application.Some of the advantages are

(1)Increases code transparency.

(2)Supports changes in data layer.

Business Tier

Through a website could talk to the data access layer directly,it usually goes through another layer called the business layer.The business layer is vital in that it validates the input conditions before calling a method from the data layer.This insures that the data input is correct  before proceeding, and can often ensure that the outputs are correct as well.

Data Access Layer

This tier acts as an interface to Data tier.This tier known how to (from which database) retrieve and store information.

Presentation Tier

This Tier is responsible for communication with the users and web service consumers and it will use objects from Business layer to response GUI raised events.