Architectures

What is an Architecture?

An architecture is a blue print image or a designed structure of any object.

why do we use an architecture?

We use architectures in-order to have complete visualization of a particular object we are working with.

There are many types of Architectures. They are:

• 1-Tier Architecture.
• 2-Tier Architecture.
• 3-Tier Architecture.
• n-Tier Architecture.

1-Tier Architecture:

One-tier architecture involves putting all of the required components for a software application or technology on a single server or platform. This kind of architecture is often contrasted with multi-tiered architecture or the three-tier architecture that's used for some Web applications and other technologies where various presentation, business and data access layers are housed separately.One-tier architecture is also known as single-tier architecture.

2-Tier Architecture:

Refers to client/server architectures in which the user interface runs on the client and the database is stored on the server. The actual application logic can run on either the client or the server. A newer client/server architecture, called a three-tier architecture introduces a middle tier for the application logic.

3-Tier Architecture: 

With the advent of internet,many people jumped to the conclusion that the das of a main frame were back. A host of 'thin-client' application were developed. Thus 3-tier architecture were born. This application runs the traditional client/server model but from a web server. The client only displays the GUI and data but has no part in producing results. Due to this type of architecture there are many benefits. Some of them are:

• Scalability.
• Better re-use.
• Improve data integrity.
• Improved security.
• reduced distribution.
• Improved availabilty.
• Hidden database structure.

Likewise, there are a few drawbacks:

• Increased complexity.
• Tools used are less compared to 2-tier (Eg: repporting tools).

N-Tier Architecture:

N-Tier architecture is an industry-proved software architecture model, suitable to support enterprise-level client/server applications by resolving issues like scalability, security, fault tolerance and etc.

N-tier application architecture provides a model for developers to create a flexible and reusable application. By breaking up an application into tiers, developers only have to modify or add a specific layer, rather than have to rewrite the enitire application over, if they decide to change technologies or scale up. In the term "N-tier," "N" implies any number -- like 2-tier, or 4-tier; basically, any number of distinct tiers used in your architecture. Application architectures are part of Layer 7 of the OSI model.

For more references : http://www.codeproject.com/Articles/430014/N-Tier-Architecture-and-Tips