WHAT IS A 3-TIER APPLICATION?

The 3-tier architecture is a fairly popular design that is used in many organizations, whether they are using AWS, not using AWS, using another cloud provider, or using on-premises resources.

This structure is associated by three tiers:

1. Tier1- Client
2. Tier2- Logic
3. Tier3- Data

1. Client Tier

In a three-tier application, the client tier is the first layer, and it typically provides us with the UI level of Tier, such as any bootstrap UI framework, using react JS or any JavaScript framework. Also by mobile devices like Android, Flutter, etc.

Therefore, tier one essentially includes a feature that users often engage with and check for utilisation. Therefore, whatever occurs in the backend, the cloud, or the services you use are connected to the first layer in some way, but the user cannot interact with the same.

Additionally, frontend engineers or mobile developers typically work in the engineering office for tier one applications. Occasionally, full stack also assumes responsibility.

2. Logic Tier

The logic layer is the project’s central component that deals with the system’s algorithmic requirements and satisfies them.

Every time a user attempts to access something in the logic tier, some logic must unavoidably execute in the background, placing logic under this tier.

As an illustration, imagine that you are a user trying to order something and that you are trying to access the payment and make payments correctly. In that case, logic must be implemented so that you can easily select your net banking option, it should be validated, and you should be able to pay securely and easily. That section is logic-tiered.

As an engineer, you can observe that both full stack engineers and backend developers handle the same issue. To accomplish it, they use many frameworks and technologies, such as node, java, python, jango, spring, etc.

3. Data Tier

The data tier is equally crucial, therefore in this tier we often acquire the data that has been saved, retrieved, searched for, etc. The data tiers work behind the scenes whenever you try to obtain certain data.

Imagine that you are attempting to find a cloth on an e-commerce website. The logic will operate, the data will be retrieved, and they will display the item you are looking for on a user interface (UI) like this. These are all things that are not possible with the data tier. Like past invoices, orders, payment histories, information from the prior year, etc.

Backend engineers are often the ones who take care of databases, however sometimes full-stack or separate database engineers also work on the same. People utilise Mysql, NoSql, Mngodb, Aurorradb, RDS services from Amazon, etc. for databases.

User Journey:

Presently, how a user navigates the three-tier application and uses it
For that, we must first deploy these three-tier applications, either on an on-premises server or a cloud server. Once it is implemented, users can use all three tiers.

Assume we are a user right now, and we want to go book a cab, so first we open our phone and launch the app.

Now a first-tier user uses an application to open it and enter it.

The tier two module awakens and begins working on the backend logic to locate the closest and available taxi when the user searches for the can after entering the destination.
Naturally, when it searches for the closest cab, it may access the data tier because there will only be one available rider there.

As a result, when a driver becomes available, Tiers 1 and 2 retrieve the necessary information and book the cab, making the user pleased.

This is how the user interacts with all three levels and how the applications function.