Maintenance<\/strong><\/li>\n<\/ol>\n\n\n\nIn this article, we will focus on Project Design: Phase 3 in the Software Development Life Cycle<\/em>.<\/p>\n\n\n\n<\/span>1. Software Requirement Specification<\/span><\/h2>\n\n\n\nThe design phase in the Software Development Life Cycle (SDLC) cannot be separated from the software requirement specification that serves as the basis for system development. In this stage, it is important to define functional and non-functional requirements in detail so that the developed system meets user expectations and works according to predefined goals.<\/p>\n\n\n\n
<\/span>1.1 Functional Requirements<\/span><\/h3>\n\n\n\nFunctional requirements refer to specific features and capabilities that must be possessed by the software system in order to function properly. Here are some examples of functional requirements in a software project:<\/p>\n\n\n\n
\n- User Authentication<\/strong>: The system must have a login mechanism to ensure that only registered users can access the service.<\/li>\n\n\n\n
- User Data Management<\/strong>: The system must allow storage, editing, and deletion of user data.<\/li>\n\n\n\n
- Notification Alerts<\/strong>: The system should be able to send notifications via email or text messages to users regarding specific activities.<\/li>\n\n\n\n
- Sales Tracking<\/strong>: The system must provide a feature to record and track sales transactions in real-time.<\/li>\n<\/ul>\n\n\n\n
How to Clearly Define System Features<\/h4>\n\n\n\n
Defining system features clearly is a crucial step for all team members to understand what needs to be done. Some methods that can be used include:<\/p>\n\n\n\n
\n- Using User Stories<\/strong>: Describe the requirements from the user’s perspective. Example: “As a user, I want to be able to order products online so that I don’t have to come to the physical store.”<\/li>\n\n\n\n
- Workflow Diagrams<\/strong>: Visualize the process and workflow with diagrams to provide a clearer picture of the interaction between various system components.<\/li>\n\n\n\n
- Product Requirement Document (PRD)<\/strong>: This document details all the functional requirements in one place, making it easily accessible and referenced by the entire team.<\/li>\n<\/ul>\n\n\n\n
<\/span>1.2 Non-Functional Requirements<\/span><\/h3>\n\n\n\nNon-functional requirements are quality aspects of the system that are not directly related to the main function but are crucial for the success of software projects. Some examples of non-functional requirements include:<\/p>\n\n\n\n
\n- Security<\/strong>: This aspect ensures that user data and information are protected from threats and cyber attacks. Examples of security specifications include end-to-end data encryption, two-factor authentication, and access audit logs.<\/li>\n<\/ul>\n\n\n\n
\n“The system must use end-to-end encryption for all data communication to protect user information from eavesdropping.”<\/p>\n<\/blockquote>\n\n\n\n
\n- Performance<\/strong>: The performance of the system must be optimized to provide quick response and efficiency in resource usage, especially under high load. Performance specifications may include maximum response time, throughput, and latency.<\/li>\n<\/ul>\n\n\n\n
\n“The system must respond to user requests in less than 2 seconds during peak load conditions.”<\/p>\n<\/blockquote>\n\n\n\n
\n- Scalability<\/strong>: Scalability allows the application to grow and adapt to increasing numbers of users or requests without reducing performance. Examples of scalability specifications include the ability to add servers without service disruption.<\/li>\n<\/ul>\n\n\n\n
\n“The application must be able to handle a 10-fold increase in the number of users without performance degradation.”<\/p>\n<\/blockquote>\n\n\n\n
Explanation of Non-Functional Requirements and Their Impact on the System<\/h4>\n\n\n\n
Non-functional requirements often influence the overall architecture of the system as well as the choice of technologies used. For example, if an application requires high scalability, a microservices-based architecture may be more suitable than a monolithic one. Additionally, attention to security aspects can determine the choice of framework or library used.<\/p>\n\n\n\n
Common examples of non-functional specifications:<\/p>\n\n\n\n
\n- Reliability<\/strong>: The application must have 99.9% uptime every month.<\/li>\n\n\n\n
- Usability<\/strong>: The user interface should be easy to use for non-technical users without the need for special training.<\/li>\n\n\n\n
- Maintainability<\/strong>: The application source code should be easily maintainable and updatable without causing significant downtime.<\/li>\n<\/ul>\n\n\n\n
Documentation of both functional and non-functional requirements is crucial in this design phase as it serves as the main reference for the development team throughout the development process. Make sure all requirements are well-documented in the Product Requirement Document (PRD) to avoid confusion or misinterpretation in the future.<\/p>\n\n\n\n
<\/span>1.2 Non-Functional Requirements<\/span><\/h3>\n\n\n\nNon-functional requirements play a crucial role in ensuring the quality and effectiveness of software systems. Unlike functional requirements that refer to specific features and functions that software must have, non-functional requirements focus more on aspects such as security, performance, and scalability.<\/p>\n\n\n\n
Security Aspect<\/h4>\n\n\n\n
Security<\/strong> is a crucial aspect that ensures the protection of user data and information from threats and cyber attacks. Examples of non-functional specifications in terms of security include data encryption, user authentication, and access control.<\/p>\n\n\n\nSystem Performance<\/h4>\n\n\n\n
The performance of the system<\/strong> must be optimized to provide quick response times and efficiency in resource usage, especially when dealing with high loads. For example, response time should be less than 2 seconds for critical transactions, and the system should be able to handle 10,000 requests per second.<\/p>\n\n\n\nApplication Scalability<\/h4>\n\n\n\n
Scalability<\/strong> allows applications to grow and adapt with an increasing number of users or demands without compromising performance. Non-functional specifications related to scalability can include the ability to add additional servers without downtime or support up to one million monthly active users.<\/p>\n\n\n\nImpact of Non-Functional Requirements<\/h4>\n\n\n\n
Non-functional requirements have a direct impact on user experience and the overall sustainability of the system:<\/p>\n\n\n\n
\n- User Experience (UX)<\/strong>: A slow or insecure system can undermine user trust and reduce satisfaction levels.<\/li>\n\n\n\n
- System Maintenance<\/strong>: Non-functional requirements such as good documentation facilitate maintenance and future system updates.<\/li>\n<\/ul>\n\n\n\n
Commonly Used Examples of Non-Functional Specifications<\/h4>\n\n\n\n
Some examples of non-functional specifications include:<\/p>\n\n\n\n
\n- Up-time<\/strong>: The system must have a minimum up-time of 99.9%.<\/li>\n\n\n\n
- Maximum Latency<\/strong>: The maximum latency for certain operations should not exceed 500 milliseconds.<\/li>\n\n\n\n
- Security Standards<\/strong>: The system must comply with industry security standards such as ISO\/IEC 27001 or GDPR.<\/li>\n<\/ul>\n\n\n\n
Clear documentation of requirements through a Product Requirement Document (PRD)<\/em> is essential for ensuring that all stakeholders have a shared understanding of what will be built. The requirement gathering process usually involves various stakeholders to ensure comprehensive coverage of both functional and non-functional aspects of the software.<\/p>\n\n\n\n<\/span>2. System Architecture<\/span><\/h2>\n\n\n\n<\/span>2.1 High-Level Architecture Design<\/span><\/h3>\n\n\n\nThe high-level architecture design is the first step in designing a comprehensive software system. In this phase, you will determine the main structure of the system and how various components will interact with each other.<\/p>\n\n\n\n
How to Create a High-Level Architecture Diagram<\/h4>\n\n\n\n
To create a high-level architecture diagram, follow these steps:<\/p>\n\n\n\n
\n- Main Component Identification<\/strong>: The first thing to do is to identify the main components of the system. This may include modules such as the database, application server, client front-end, and external services.
Example<\/em>: In an e-commerce application, the main components may include the product management module, user management module, and payment module.
<\/li>\n\n\n\n- Determine Interactions Between Components<\/strong>: Once the main components are identified, the next step is to determine how they will interact with each other. This interaction often involves the use of APIs or other communication protocols.
Example<\/em>: The user management module may need to communicate with the payment module to verify user payment information.
<\/li>\n\n\n\n- Select Appropriate Symbols and Notations<\/strong>: Use standard symbols and notations to depict various elements and relationships between elements in your architecture diagram. Some common notations include:<\/li>\n<\/ol>\n\n\n\n
\n- Box<\/strong>: To represent a component or module.<\/li>\n\n\n\n
- Arrow<\/strong>: To indicate the flow of data or control between components.<\/li>\n\n\n\n
- Dotted Line<\/strong>: To show optional or conditional relationships.<\/li>\n<\/ul>\n\n\n\n
\n- Include Important Details<\/strong>: Include important details such as the type of database used (relational or NoSQL), server technology (e.g., Node.js or Django), and front-end framework (such as React or Angular).
Example<\/em>: “The application server uses Spring Boot for the backend and React for the frontend.”
<\/li>\n\n\n\n- Validate with Development Team<\/strong>: Before finalizing the diagram, validate it with the entire development team to ensure that everyone has a shared understanding of the system architecture.
Example<\/em>: Conduct a brainstorming session with team members to get input and make adjustments if necessary.<\/li>\n<\/ol>\n\n\n\nKey Elements to Consider<\/h4>\n\n\n\n
Some key elements to consider when designing a high-level architecture include:<\/p>\n\n\n\n
\n- Modularity<\/strong>: Ensure that each component can be developed separately without depending on other components.
Advantages<\/em>: Facilitate development and testing processes.
<\/li>\n\n\n\n- Scalability<\/strong>: Design the system in such a way that it can handle increasing workloads without requiring significant changes to the overall architecture.
Example<\/em>: Using a load balancer to distribute traffic to multiple servers.
<\/li>\n\n\n\n- Security<\/strong>: Integrate security mechanisms from the beginning into the architectural design to protect data and maintain system integrity.
Example<\/em>: Adding an SSL\/TLS encryption layer between the client and server.
<\/li>\n\n\n\n- Performance Optimization<\/strong>: The architectural design should consider performance aspects such as low latency and high throughput.
Example<\/em>: Using server-side caching to accelerate data access.
<\/li>\n\n\n\n- Interoperability<\/strong>: Ensure that the system can integrate well with external services or other systems that may be used by stakeholders.
Example<\/em>: Using RESTful or GraphQL APIs for inter-service communication.<\/li>\n<\/ul>\n\n\n\nBy following these guidelines, you can design a high-level architecture diagram that is not only effective but also scalable and secure. This process will provide a visual roadmap for the entire development team, ensuring that everyone works towards the same goal with a consistent understanding of the system structure.<\/p>\n\n\n\n
<\/span>2.2 Component Interaction<\/span><\/h3>\n\n\n\nIn software architecture, system components interact with each other in various ways and protocols. A deep understanding of inter-component interaction<\/strong> is crucial to ensure seamless and efficient integration. One of the main methods to achieve this is through the use of Application Programming Interfaces (APIs)<\/strong>.<\/p>\n\n\n\nHow Components Interact<\/h4>\n\n\n\n\n- API<\/strong>: APIs act as bridges between components, allowing them to communicate and exchange data.<\/li>\n<\/ul>\n\n\n\n
\nExample<\/em>: In an e-commerce application, an API can be used to connect the payment module with the inventory management system.<\/p>\n<\/blockquote>\n\n\n\n\n- Communication Protocol<\/strong>: Protocols such as HTTP\/HTTPS, WebSockets, and gRPC are often used to ensure secure and efficient data transfer between components.<\/li>\n<\/ul>\n\n\n\n
\nHTTP\/HTTPS<\/em>: Used in web applications for communication between clients and servers.<\/p>\n<\/blockquote>\n\n\n\n\nWebSockets<\/em>: Ideal for applications that require real-time communication such as chat applications.<\/p>\n<\/blockquote>\n\n\n\n\n- Data Serialization<\/strong>: This technique converts objects into a format that can be transmitted over a network, such as JSON or XML.<\/li>\n<\/ul>\n\n\n\n
The Importance of System Integration<\/h4>\n\n\n\n
Good integration between components ensures that the system works as a coherent whole. Some benefits of good integration include:<\/p>\n\n\n\n
\n- Operational Efficiency<\/strong>: Reducing duplication of work and improving coordination among development teams.<\/li>\n\n\n\n
- Scalability<\/strong>: Facilitating the addition or replacement of components without disrupting the overall performance of the system.<\/li>\n<\/ol>\n\n\n\n
A well-designed software architecture enables efficient interaction between components, keeping the system performance optimal even with increased load or complexity.<\/p>\n\n\n\n
By understanding these concepts, you can design more robust and easily adaptable software systems to meet changing business needs.<\/p>\n\n\n\n
<\/span>3. Prototyping and Design Documentation<\/span><\/h2>\n\n\n\n<\/span>3.1 Prototype Development