Chapter 6 Essentials of Design and the Design Activities

Chapter Overview

  • Chapter Title: Systems Analysis and Design in a Changing World, 7th Ed

  • Authors: Satzinger, Jackson & Burd

  • Edition: 7th Edition

  • Copyright: ©2016. Cengage Learning.

What Is Systems Design?

  • Systems Design describes the process of detailing how a system will be built.

  • Key aspects include contrast with systems analysis, design activities, system controls, and security considerations.

Systems Analysis vs. Systems Design

  • Analysis: Focuses on determining what is required for the system.

  • Design: Details how the requirements will be implemented into an operational system.

  • Relationship: Design acts as a bridge between analysis and implementation.

Key Objectives of Systems Design

  • Define, organize, and structure components of the final solution.

  • Serve as a blueprint for construction and implementation.

  • Document results to coordinate work across teams.

Design Activities

Model Building

  • Design is fundamentally a model building activity.

  • Model complexity depends on the project's formality; i.e., Agile projects may require fewer but still significant models.

  • Jumping directly into programming without a solid design can lead to suboptimal solutions requiring rework.

Corresponding Design Components

  1. Environment: Considerations for external systems and network communications.

  2. Application Components: Focuses on individual software units and how to package them.

  3. User Interface: Critical impact on user productivity and may require adaptation across multiple devices.

  4. Database: Often utilizes Relational Database Management Systems (RDBMS) and entails addressing various technical challenges.

  5. Software Classes and Methods: Define functionality and structure in programming terms.

Integrity and Security Controls

Types of Controls

  • Integrity Controls: Ensure the accuracy and validity of inputs, outputs, and data throughout the system.

  • Security Controls: Protect assets from internal and external threats.

Objectives of Integrity Controls

  • Facilitate proper handling of business transactions.

  • Safeguard database assets.

Important Control Mechanisms

  • Input Controls: Prevent erroneous data entry (e.g., value limits, completeness checks).

  • Output Controls: Ensure data accuracy and proper distribution (e.g., labeled reports).

Security Considerations

Access Controls

  • Manage who can access what within the system and data.

  • Use of authentication methods including multifactor verification.

Data Protection Strategies

  1. Encryption and Decryption: Essential for protecting stored data and data in transit.

  2. Digital Signatures: Authenticate documents and transactions, ensuring integrity.

  3. Secure Protocols: Use of SSL, TLS, and HTTPS to secure data transmission over the internet.

Summary of Design Activities

  • Environmental Design: Assess external systems and existing technology architecture.

  • Application Component Design: Define functional scope and programming parameters for software components.

  • User Interface Design: Develop user-friendly and efficient interfaces tailored to various environments.

  • Database Design: Transition data models into relational databases while addressing performance issues.

    Methodology Design: Specify software classes and methods that define system operations.

Examination of Security Framework

  • Focus on integral approaches to secure data and transactions while preventing fraud and ensuring operational continuity.