Sign in Subscribe

HLD (High Level Design)

Last updated on 

High Level Design (HLD) is a crucial phase in the software development life cycle (SDLC) that outlines the software architecture, system components, and their interactions. The HLD provides a comprehensive view of the software system and helps in the identification of potential issues, risks, and improvements. In this article, we will discuss what is HLD, its importance, and the key steps involved in creating a high-level design.

What is HLD?

HLD refers to the process of defining and designing the overall architecture of a software system. The primary goal of HLD is to define the system's structure and its components, the way these components interact, and the communication protocols they use. The HLD defines the system's functionalities and features and identifies the potential risks and issues that may arise during the development process.

The HLD should provide a clear and concise overview of the software system's high-level design, including the hardware and software components, network architecture, user interface, database schema, security mechanisms, and other critical aspects. The HLD should be created by the software architect, who is responsible for developing the overall software system design.

Importance of HLD

The HLD is essential in the software development process, as it lays the foundation for the development team to build the system's actual components. Here are some of the key reasons why HLD is so important:

  1. Provides a clear and concise understanding of the system's architecture: The HLD outlines the overall structure of the software system and provides a clear understanding of how the various components of the system interact with each other.
  2. Helps identify potential issues and risks: The HLD helps in identifying potential issues and risks that may arise during the development process, such as compatibility issues, scalability problems, or security vulnerabilities.
  3. Enhances communication and collaboration: The HLD provides a common language and framework for communication and collaboration between different stakeholders involved in the software development process, such as developers, project managers, and clients.
  4. Facilitates software testing and maintenance: The HLD serves as a blueprint for the development team to build the actual components of the system. It also provides a basis for testing and maintaining the software system in the future.

Steps involved in creating HLD

The HLD process involves the following key steps:

  1. Requirements gathering: The first step in creating an HLD is to gather requirements. The software architect should work closely with the client or end-user to understand their needs and expectations from the software system.
  2. Identifying the system components: Based on the requirements, the software architect should identify the various components that the software system will comprise. These may include hardware components, software modules, databases, and other system components.
  3. Defining the system architecture: Once the system components have been identified, the software architect should define the system architecture. This involves defining the system's overall structure, the way the components will interact, and the communication protocols they will use.
  4. Creating a functional specification: The functional specification defines the system's functionalities and features. This includes the software system's behavior, data flow, and user interface.
  5. Creating a technical specification: The technical specification defines the system's technical details, such as the hardware and software components, network architecture, security mechanisms, and database schema.
  6. Reviewing and refining the HLD: Once the HLD has been created, it should be reviewed and refined to ensure that it meets the requirements and addresses any potential issues or risks.
  7. Getting approval: Once the HLD has been finalized, it should be submitted for approval by the client or end-user. The HLD should be signed off before moving on to the next phase of the software development process.

Conclusion

In conclusion, High Level Design (HLD) is a critical phase in the software development life cycle (SDLC) that outlines the software architecture, system components, and their interactions. The HLD provides a comprehensive view of the software system and helps in the identification of potential issues, risks, and improvements. It is important to note that the HLD is a high-level view of the software system and does not go into the details of implementation.

The HLD should be created by the software architect, who is responsible for developing the overall software system design. The HLD process involves several key steps, including requirements gathering, identifying the system components, defining the system architecture, creating a functional specification and a technical specification, reviewing and refining the HLD, and getting approval from the client or end-user.