Layered architecture

Layered architecture is a software architecture pattern that organizes a system into distinct layers, where each layer performs specific functions and has defined responsibilities. The layers are hierarchical, with higher layers depending on lower layers. This architectural style promotes modularity, separation of concerns, and ease of maintenance.

• Modularity: Layered architecture promotes modular design by dividing the system into self-contained layers. Each layer focuses on specific tasks and responsibilities, allowing for easier development, testing, and maintenance of individual layers.

• Separation of Concerns: By separating different concerns into distinct layers, this architecture reduces complexity and improves clarity. Each layer is responsible for a specific aspect of the system's functionality, such as user interface, business logic, or data storage.

• Abstraction and Encapsulation: Layers provide abstractions that hide the internal implementation details of other layers. They encapsulate their logic and expose well-defined interfaces, allowing for loose coupling between layers and facilitating change management.

• Hierarchical Structure: Layers are organized in a hierarchical structure, where each layer relies on the layer beneath it. This structure facilitates the flow of data and control within the system, with higher-level layers building upon the services provided by lower-level layers.

• Ease of Maintenance: Due to the separation of concerns and modular design, layered architecture simplifies maintenance and updates. Changes made in one layer are less likely to affect other layers, which allows for localized modifications and reduces the risk of unintended side effects.

While the specific layers and their names may vary depending on the system and its requirements, a typical layered architecture consists of the following layers:

• Presentation Layer: Also known as the User Interface (UI) layer, this layer is responsible for handling user interactions, displaying information, and receiving user input. It may include components such as web interfaces, mobile app interfaces, or graphical user interfaces (GUI).

• Application Layer: The Application layer, also called the Business Logic layer, contains the core logic and rules that govern the system's behavior. It orchestrates the interaction between different components and implements the specific business processes and workflows.

• Domain Layer: The Domain layer represents the core domain concepts, business entities, and rules. It encapsulates the business logic and defines the behavior of the system's entities, such as entities related to customers, orders, or products. This layer often incorporates domain-driven design principles.

• Data Access Layer: Also known as the Persistence layer, this layer provides access to the data storage mechanisms, such as databases or external services. It handles data retrieval, storage, and manipulation, ensuring data integrity and consistency.