In Depth Notes on Computer System Planning and Management

Topic 1.1.1: Context for New Systems

  • A new system is created to replace an outdated, inefficient, or redundant one.
  • The goal is to reduce flaws and errors present in the old system.
  • Example scenario: Assessing if a small bookshop would benefit from a computerized system.

Topic 1.1.2: Change Management

  • Definition: Transitioning individuals from their current state to a desired future state.
  • Importance: Ensures stakeholder acceptance and minimized negative impacts during transitions.
  • Example: Changing operating systems in a small business requires training for employees.

Reasons Why Change is Difficult:

  • Resistance from users.
  • Removal of features users are accustomed to.
  • Complexity of new systems.
  • Potential for data loss during migration.
  • High costs involved.
  • Compatibility issues with existing software/hardware.

Topic 1.1.3: Compatibility Issues

  • Legacy systems may cause issues during mergers, especially in international contexts.
  • Issues include software compatibility and language differences.

Reasons for Using Legacy Systems:

  • Old data remains unconverted to new systems.
  • Functionality from outdated software is still necessary.
  • Continued interaction with old hardware.

Disadvantages of Legacy Systems:

  • High maintenance costs.
  • Lack of tech support.
  • Vulnerable to security risks.
  • Difficulty integrating new systems.

Topic 1.1.4: Local vs. Remote Systems

Local Computing:

  • The client provides their own hardware.
Advantages:
  • Enhanced security.
  • Controlled backups.
  • Compatibility with legacy software.
Disadvantages:
  • Hardware costs.
  • Technical support challenges.
  • Collaboration difficulties.

Software-as-a-Service (SaaS):

  • Client uses servers from the software manufacturer.
Advantages:
  • No personnel costs for maintenance.
  • Access to manufacturer’s expertise.
Disadvantages:
  • Data security risks.
  • Potential for inconvenient maintenance times.

Topic 1.1.5: Installation Processes

  1. Direct Changeover
    • Fast and cost-effective.
    • Risks unrecoverable losses from old systems.
  2. Parallel Running
    • Old and new systems operate simultaneously.
    • Expensive and memory-intensive.
  3. Phased Changeover
    • Step-by-step implementation, allowing for error correction.
    • Time-consuming and costly.
  4. Pilot Running
    • Testing the new system in a single branch before full rollout.
    • Effective but costly.

Topic 1.1.6: Data Migration Issues

  • Data migration can face challenges like incompatible formats, structural differences, and validation conflicts.

Topic 1.1.7: Types of Testing

  • Alpha Testing: Conducted internally before public release.
  • Beta Testing: Open to external users for feedback.
  • Dry-Run Testing: Programmers verify algorithms manually.
  • Unit Testing: Individual parts tested separately.
  • Integration Testing: Ensures system components work together.
  • User Acceptance Testing: Verifies system meets customer needs.
  • Black/White Box Testing: Analyzes application functionality vs. internal design.

Topic 1.1.9: User Documentation Methods

Types of Documentation:

  • Internal Documentation: Code structure and comments.
  • User Documentation: Guides on using programs.

Documentation Formats:

  • Online Manuals (multimedia capabilities).
  • Offline Manuals (no tech dependency).
  • FAQs, Live Chat, and Remote Desktop Support.

Topic 1.1.10: User Training Methods

Types of Training:

  • Self-instruction: Users learn independently.
  • Formal Classes: Structured learning in groups.
  • Remote/Online Training: Tailored instruction but at a higher cost.

Topic 1.1.11: Causes of Data Loss

  • Causes: Accidental deletion, administrative errors, natural disasters, hardware failures.
  • Solutions: Backups, regular maintenance, using antivirus software.

Topic 1.1.12: Consequences of Data Loss

  • Varies by context; for example, in healthcare, it can lead to critical failures like loss of patient information.

Topic 1.1.13: Methods to Prevent Data Loss

  • Failover Systems: Backup systems operational upon error detection.
  • Redundancy: Same data stored in multiple locations.
  • Offsite Storage: Local data kept in external locations.

Topic 1.1.14: Managing Releases and Updates

  • Patches: Fix specific issues.
  • Updates: Improve functionality.
  • Upgrades: Major revisions requiring payment.

Topic 1.2.1: Definitions

  • Hardware: Physical computer components.
  • Software: Programs controlling hardware.
  • Peripheral: Devices enhancing computer interaction.
  • Network: Connected computer systems for resource sharing.
  • Human Resources: Personnel operating the systems.

Topic 1.2.2: Computer Roles

  • Client: Accesses resources such as files.
  • Server: Hosts resources for sharing.

Topic 1.2.3: Social & Ethical Issues in Networking

Social Issues:

  • Dominance of English, Over-connectedness, Cyberbullying, Identity Theft, Digital Distraction.

Ethical Issues:

  • Copyright Violations, Privacy Invasion, Anonymity, Criminal Activities.

Topic 1.2.4: Stakeholders in New System Planning

  • Include developers, end-users, critics, software manufacturers, brokers, investors, and government.

Topic 1.2.5: Methods for Gathering Requirements

  • Observation: Monitoring with natural behavior observation.
  • Surveys: Data collection using structured feedback forms.
  • Interviews: Direct stakeholder engagement for feedback.

Topic 1.2.6: Information-Gathering Techniques

  • Examining existing systems, competitor analysis, literature searches.

Topic 1.2.7: Representing System Requirements

  • Techniques: flow charts, data flow diagrams, structure diagrams.

Topic 1.2.8: Prototypes

  • Early versions to demonstrate proposed systems, useful for identifying issues early and facilitating user/client understanding.

Topic 1.2.9: Importance of Iteration

  • Key in design for ensuring issues are resolved and improvements made.

Topic 1.2.10: End-User Involvement Consequences

  • Missing user feedback can lead to products that do not meet user needs, resulting in lost productivity and potential legal problems for the company.

Topic 1.2.11: Social & Ethical Issues with IT Systems

  • Digital divide, less social interaction, privacy, reliability, and worker substitution.

Topic 1.2.12: Usability Definition

  • Usability: Ease of use and learnability of systems focusing on user interaction.

Usability Factors:

  • Accessibility: Design for users with disabilities.
  • Learnability: First-time usage efficiency.
  • Errors: Frequency and recovery.
  • Efficiency: Speed of task completion.

Topic 1.2.13: Usability Problems in Digital Devices

  • Examples in GPS, tablets, PCs, mobile phones, etc.

Topic 1.2.14: Improving Accessibility

  • Methods include touch screens, voice recognition, and Braille.

Topic 1.2.15: Usability Problems in Systems

  • Challenges with voice recognition software, automated feedback systems.

Topic 1.2.16: Human-Machine Interaction Implications

Moral/Ethical:

  • Use of AI in warfare, potential for criminal use.

Social:

  • Reduced human interaction.

Economic:

  • Job displacement from automation.

Environmental:

  • Impact of carbon emissions from decreased travel due to automation.