IS5411 Lab Plog 1: Overview of Design Techniques

IS5411 System Design: Core Tools Summary

A concise guide to the essential tools/techniques used in system design and analysis. This would be kept till you guys finish the final examination, best wishes!^^

Part 1. Identifying A Business Problem (Lab 1-4)

  • Interview: Stakeholder conversations, aims to gather requirement narratives and identify system needs.
    • Do not ask abstract questions, “big” questions, or questions that require cognitive load to answer.
      • Make the interviewee comfortable.
    • Do not strictly follow the interview outline.
      • An interview is a dynamic process.
      • Better adjust your question based on previous answers.
    • Focus on the core requirement rather than:
      • 1) specific details out of the focused use case (e.g., repairment)
      • 2) risk management: what if… (e.g., I have changed my mind)
  • (Intermediate) Use Case Diagram`: Visual map showing what use cases exist and which actors interact with each one. Provides high-level system functionality overview.

Part 2. Designing the Database (Lab 5-6)

  • Noun Technique: Extract nouns from interview narratives to identify data entities that become database tables.
    • Criteria of exclusion in the noun table (IOSO)
      • Irrelevant / Not target (Within the scope? Unique to the process?)
      • Only 1 of these items?
      • Synonym
      • Output/input
    • When using the noun techniques, for the first column, better to put the modifier + noun.
      • E.g., doctor’s office
    • Attributes are based on common sense (when you do the final examination)
  • Class Diagram: Blueprint defining entities, attributes, and relationships for database structure.

Part 3. Designing Use Cases

  • Step 1. what are detailed workflows (Lab 7)
    • Use Case Description: Step-by-step narrative of detailed workflows (how users accomplish goals) within the system.
  • Step 2. visual workflow & investigate information flow (Lab 8-9)
    • Activity Diagram: Visual workflow showing detailed actor processes, decision points, and loops.
    • Analysis SSD: Documents user-system information exchange. Focuses on inputs and outputs (information cross the boundary between user and system).
  • Step 3. use case realization: design a specific use case! (Lab 10)
    • 1. Input and output & data retrieval logic:
    • 2. Technical logic design:
      • Design SSD: Specifies technical logic with method calls, parameters, and return values
    • 3. Finalization: