Requirement Determination: A Critical Phase in System Analysis and Design

Requirement determination is a fundamental phase in the Systems Development Life Cycle (SDLC), where the analyst plays a pivotal role in identifying and defining the functional requirements for a new system. This article aims to provide an expert overview of requirement determination, drawing upon insights from the provided sources.

The Analysis Phase

Requirement determination is an integral part of the analysis phase in the SDLC. During this phase, the analyst meticulously examines the existing system, gathers relevant information, and analyzes the system’s strengths, weaknesses, and areas for improvement. The primary objective is to gain a comprehensive understanding of the current system and establish a solid foundation for designing the new system.

Deliverables of the Analysis Phase

The primary deliverable of the analysis phase is the system proposal, which serves as a comprehensive document outlining the requirements for the new system. The system proposal encompasses various sections, including the requirements definition statement, which plays a crucial role in defining the scope and objectives of the new system.

Types of Requirements

Requirements can be categorized into different types based on their nature and purpose. Common categories include:

• Business RequirementsThese requirements align with the organization’s strategic goals and objectives. They define the overall purpose and scope of the new system.
• User RequirementsThese requirements originate from the end-users of the system. They specify the specific tasks and functions that the system must perform to meet the users’ needs.
• Functional RequirementsThese requirements describe the specific functions and capabilities that the system must possess. They define the system’s behavior and how it should respond to various inputs and conditions.
• Nonfunctional RequirementsThese requirements specify the constraints and limitations that the system must adhere to. They encompass aspects such as performance, reliability, security, and usability.

Requirements Definition Statement

The requirements definition statement (RDS) is a critical component of the system proposal. It outlines the purpose and structure of the requirements for the new system. The RDS typically includes the following sections:

Provides an overview of the purpose and scope of the RDS.
• ScopeClearly defines the boundaries of the new system and identifies the specific areas that will be addressed.
• Functional RequirementsLists and describes the specific functions and capabilities that the system must possess.
• Nonfunctional RequirementsSpecifies the constraints and limitations that the system must adhere to.
• GlossaryDefines and explains any specialized terms or acronyms used in the RDS.

Requirements Elicitation Techniques

To effectively gather requirements, analysts employ a variety of techniques, each serving a specific purpose. Common techniques include:

• InterviewsOne-on-one or group discussions with stakeholders to gather their insights and perspectives on the new system.
• Joint Application Development (JAD) SessionsCollaborative workshops where stakeholders work together with the analyst to define and prioritize requirements.
• QuestionnairesStructured surveys distributed to stakeholders to collect their feedback and opinions.
• Document AnalysisReview of existing documentation, such as process flows, reports, and manuals, to identify requirements.
• ObservationDirect observation of users performing their tasks to gain insights into their needs and requirements.

Analysis Strategies for Discovering Requirements

In addition to elicitation techniques, analysts utilize various strategies to discover requirements. These strategies help to uncover hidden or implicit requirements that may not be readily apparent. Common strategies include:

• BrainstormingA group activity where participants generate a wide range of ideas and suggestions for requirements.
• PrototypingCreating a preliminary version of the system to demonstrate its functionality and gather feedback from stakeholders.
• Use Case AnalysisIdentifying and analyzing the different ways in which users will interact with the system.
• Data Flow AnalysisTracing the flow of data through the system to identify potential bottlenecks or areas for improvement.

Conclusion

Requirement determination is a critical phase in system analysis and design, as it lays the foundation for the successful development of a new system. By employing a combination of elicitation techniques and analysis strategies, analysts can effectively gather and define the requirements for the new system, ensuring that it meets the needs of the organization and its users.

References

• System Analysis and Design, Fifth Edition
• Requirements Determination

FAQs

What is requirement determination?

Requirement determination is the process of identifying, analyzing, and documenting the requirements for a new or modified system. It involves gathering input from stakeholders, understanding their needs, and defining the specific functions and capabilities that the system must possess.

Why is requirement determination important?

Requirement determination is important because it forms the foundation for the successful development of a new system. By clearly defining the requirements, the development team can ensure that the system meets the needs of the users and the organization.

What are the different types of requirements?

There are several types of requirements, including:

• Business requirements: These requirements define the overall goals and objectives of the system from a business perspective.
• User requirements: These requirements specify the specific tasks and functions that the system must perform to meet the needs of the users.
• Functional requirements: These requirements describe the specific functions and capabilities that the system must possess.
• Nonfunctional requirements: These requirements specify the constraints and limitations that the system must adhere to, such as performance, reliability, and security.

What are some techniques for gathering requirements?

There are several techniques for gathering requirements, including:

• Interviews: One-on-one or group discussions with stakeholders to gather their insights and perspectives.
• Joint Application Development (JAD) Sessions: Collaborative workshops where stakeholders work together with the analyst to define and prioritize requirements.
• Questionnaires: Structured surveys distributed to stakeholders to collect their feedback and opinions.
• Document Analysis: Review of existing documentation, such as process flows, reports, and manuals, to identify requirements.
• Observation: Direct observation of users performing their tasks to gain insights into their needs and requirements.

What are some strategies for analyzing requirements?

There are several strategies for analyzing requirements, including:

• Brainstorming: A group activity where participants generate a wide range of ideas and suggestions for requirements.
• Prototyping: Creating a preliminary version of the system to demonstrate its functionality and gather feedback from stakeholders.
• Use Case Analysis: Identifying and analyzing the different ways in which users will interact with the system.
• Data Flow Analysis: Tracing the flow of data through the system to identify potential bottlenecks or areas for improvement.

What is a requirements specification document?

A requirements specification document (RSD) is a formal document that captures the complete set of requirements for a new or modified system. It serves as a contract between the stakeholders and the development team, and provides a detailed description of the system’s functionality, performance, and other characteristics.

What are some common challenges in requirement determination?

Some common challenges in requirement determination include:

• Incomplete or unclear requirements: Stakeholders may not be able to fully articulate their needs, or may not be aware of all the requirements that the system must meet.
• Conflicting requirements: Different stakeholders may have different or even conflicting needs, which can make it difficult to prioritize and resolve requirements.
• Changing requirements: Requirements may change over time as the project progresses, due to new insights, changes in the business environment, or other factors.

How can requirement determination be improved?

Requirement determination can be improved by:

• Actively involving stakeholders: Engaging stakeholders throughout the requirement determination process ensures that their needs are understood and considered.
• Using a variety of techniques: Employing a combination of requirement gathering techniques can help to identify and capture a more complete set of requirements.
• Documenting requirements clearly and concisely: A well-written RSD helps to ensure that the requirements are understood by all stakeholders and can be easily implemented by the development team.