The world of Information technology is evolving every day, making ways for new and advance software and applications. However, developing an app from scratch is quite strenuous, as it requires time, resources, as well as finances. Therefore, the programmers needed an Hobe Sounds architects model, which allow them to create flexible and reusable applications. As a result, the concept of ‘N-tier’ architectural model” came into light. Often known as Multi-tier architectural model, it is an application development system divided into different layers or tiers. The default values of “N” is kept three. This structural concept serves as an integral element, while developing web-based software applications.

Entity Tier: Also known as the presentation layer, this top most layer acts as the face of the application, which directly interacts with the user. This incorporates features which are often found in web apps, such as control and input validation. This layer communicates with other layers, by providing the relevant and processed information to them.

Business Tier: Often termed as middle layer, or logic layer, this tier serves as the ‘brain’ of the entire app. Filling the gap between the presentation layer and the data layer, the Business layer sometimes processes the data, otherwise ensures the smooth flow of information. This layer is the heart of all the processes, that takes place inside the application.

The logic layer interacts with the data layer to fetch the required information. Once received, it apply the business rules from the earlier gathered details.

Data Tier: This layer of the application interacts with the database servers, and fetches the required information. The information is stored and delivered without any questions i.e. the layer is neutral and independent of any logic. However, this layer accounts for the application’s performance, faster the data gathering, better the application speed.

The data retrieval in the layer happens in the form of data selection, query, insertion, update, or deletion of information to and from the database.

Scalability: A layered structure facilitates the required amount of flexibility, and scalability to the overall system. At any point of the process, the layers can be upgraded or interchanged, due to their low-level of dependency on each other for proper functioning.

Ease in Implementing Changes: Software systems need upgrades, according to the project requirements. Often the modifications are carried out, as a change or enhancement in the functionality, addition of a brand-new module, or a new hardware, and so on. In most cases, modifications occur during the initial phase of development, or after the alpha-test. Using the multi layer system architecture from the start itself, allows you to minimize the effect of the modifications carried out on the single layer, on the entire system.

Ease of Maintenance: It is a universal truth that an organized structure is easy to maintain. In the same way, the source code is easy to debug, and maintain, if neatly organized into a multiple tiered structure. As for a programmer, the layer architecture allows locating of the sections, wherein the changes need to be implemented. Furthermore, a well-organized architecture ensures ease in system upgrades or enhancement addition, which are often time-consuming.