Requirements analysis in LLD - System Design Exercise

Design: Requirements Analysis Process

Focus on the process of gathering, analyzing, and documenting requirements for software systems. Out of scope are implementation details and coding.

Functional Requirements

FR1: Identify and document functional requirements clearly

FR2: Capture non-functional requirements such as performance and security

FR3: Prioritize requirements based on stakeholder needs

FR4: Ensure requirements are testable and measurable

FR5: Manage changes to requirements throughout the project lifecycle

Non-Functional Requirements

NFR1: Requirements must be understandable by both technical and non-technical stakeholders

NFR2: Analysis should be completed within project timelines to avoid delays

NFR3: Requirements must be feasible within given technology and budget constraints

Think Before You Design

Questions to Ask

❓ Question 1

❓ Question 2

❓ Question 3

❓ Question 4

❓ Question 5

Key Components

Stakeholder interviews and workshops

Use case and user story documentation

Requirement prioritization matrix

Traceability matrix linking requirements to tests

Change management process

Design Patterns

MoSCoW prioritization (Must have, Should have, Could have, Won't have)

User story mapping

Requirements traceability

Iterative refinement and validation

Reference Architecture

  +-------------------+       +---------------------+       +-------------------+
  | Stakeholder Input | ----> | Requirements Analyst | ----> | Requirements Doc  |
  +-------------------+       +---------------------+       +-------------------+
           |                            |                             |
           |                            |                             |
           v                            v                             v
  +-------------------+       +---------------------+       +-------------------+
  | Use Cases & Stories|       | Prioritization Tool |       | Traceability Matrix|
  +-------------------+       +---------------------+       +-------------------+

Components

Stakeholder Input

Interviews, Surveys, Workshops

Gather initial requirements and expectations from users and stakeholders

Requirements Analyst

Manual analysis, Documentation tools

Analyze, clarify, and document requirements

Requirements Document

Word processors, Requirement management tools

Centralized, clear, and accessible record of requirements

Use Cases & User Stories

Templates, Agile tools

Describe system interactions and user needs

Prioritization Tool

Spreadsheets, Specialized software

Rank requirements to focus on critical features

Traceability Matrix

Requirement management software

Link requirements to design and test cases for validation

Request Flow

1. Stakeholders provide input through interviews and workshops.

2. Requirements analyst collects and organizes this input.

3. Use cases and user stories are created to represent functional needs.

4. Requirements are prioritized using a prioritization tool.

5. A requirements document is created and shared with stakeholders.

6. Traceability matrix is maintained to ensure coverage in design and testing.

7. Change requests are managed and updated in the documentation.

Database Schema

Entities: Stakeholder (id, name, role), Requirement (id, description, type, priority, status), UseCase (id, title, description), TraceabilityLink (requirement_id, design_id, test_id). Relationships: Stakeholder to Requirement (1:N), Requirement to UseCase (N:1), Requirement to TraceabilityLink (1:N).

Scaling Discussion

Bottlenecks

Difficulty managing large numbers of requirements and stakeholders

Keeping documentation up to date with frequent changes

Ensuring all requirements are testable and traceable

Communication gaps between technical and non-technical teams

Solutions

Use specialized requirement management tools with collaboration features

Implement automated traceability and change tracking

Adopt iterative and incremental requirement refinement

Facilitate regular cross-team meetings and reviews

Interview Tips

Time: Spend 10 minutes understanding the problem and clarifying requirements, 20 minutes outlining the process and components, 10 minutes discussing challenges and scaling, 5 minutes for questions.

Importance of clear and testable requirements

Balancing stakeholder needs and technical feasibility

Use of prioritization and traceability to manage complexity

Handling changes and communication effectively