Before explaining single-tier applications, let us first understand the term “tier.” We can think of tiers are layers. These layers are divided into three parts: Presentation Layer (User Interface), Application Layer (Backend Login), Data Layer (Database). Now let us understand the use of these layers.
Presentation Layer: The presentation layer is also known as the client layer. This is the topmost level of an application. This layer’s primary function is to translate results into an interface that the end-user can understand.
Application Layer: This layer contains the business logic of the application. This data helps in the processing of the data between the presentation layer and the data layer. The complete business logic is written in this layer. This layer also picks up data from the data layer and sends it to the presentation layer depending on the requirement.
Data Layer: This layer stores the information. This layer sends the information to the application layer for the data to be processed and be presented to the presentation layer. It connects to the database and performs the required action (CRUD operations).
A single-tier application is an application where the backend logic, database, and user interface lies in the same machine. There are many single-tier applications, but the most famous ones are MS office, Desktop-based games.
Why Single tier applications?
Single tier applications are in a single machine; hence there is no network latency. Since the data is located on the same machine, the data is readily available, and there is no need to request a database server to receive data. Since the data is present in the same machine, data security is guaranteed.
Why not Single tier applications?
The application depends on the configuration of the user’s machine. This dependency can lower the application’s performance, and the look of the application might be incompatible.
The most significant disadvantage of a single-tier application is that it is not under the developer’s control. Suppose the application is packaged, uploaded, and is downloaded by a user. In that case, the application cannot be updated until the user manually downloads the application again or installs a new patch. This is a severe issue, as the developer might lose users if the application is buggy.
The application can easily be reverse-engineered, limiting the security of the application.