What is N-tire Architecture ?

The n-Tier application has three tiers or layers; they are called the presentation layer, the business layer and the data layer. Each layer interacts with the layer directly below, and has specific function to perform. The presentation layer is responsible for displaying the user interface to the end user. The programmer uses this layer for designing the user interface and to transfer data. In ASP.NET, ASPX pages, user controls, server controls and sometimes security related classes and objects are used to support the presentation layer.

The business layer works as a go-between to transfer the data from presentation layer. In the three-tier architecture, the data access layer does not interact directly with the presentation layer. The architecture in ASP.NET includes using SqlClient or OleDb objects to retrieve, update and delete data from SQL Server or other databases and passing the data retrieved to the presentation layer in a DataReader or DataSet object, or a custom collection object. The data layer gets the data from the business layer and sends it to the database or vice versa.

The main advantage of using n-Tier is that the complexity associated with the business and the process is reduced and is easy to implement. The elements of performance, scalability and future development issues need to be considered when deciding on the architecture of the application.