Unit 5: Business System Development and Implementation




Business System Development and Implementation

Developing a business system is not just about coding; it involves testing, documentation, proper implementation, hardware/software selection, and ongoing maintenance. Each step ensures the system is reliable, efficient, and aligned with business goals.

System Testing and Quality Assurance (QA)

System testing ensures that the developed system meets business requirements and performs correctly. QA is the process to maintain high-quality standards throughout development.

Types of Testing

TypePurposeExample
Unit TestingTest individual components/modulesTesting login functionality separately
Integration TestingEnsure modules work together correctlyPayment gateway integration with order processing
System TestingTest the complete system end-to-endE-commerce website testing all features
User Acceptance Testing (UAT)Verify system meets user requirementsEnd-users test the dashboard and reports
Performance TestingCheck speed, scalability, and response timeLoad testing during Black Friday sale
Security TestingIdentify vulnerabilities and threatsPenetration testing for banking applications

QA Techniques: Code reviews, automated testing, regression testing, and adherence to software development standards.

Documentation for Systems

Documentation ensures that the system’s design, processes, and usage are recorded, helping in maintenance, audits, and knowledge transfer.

Types of Documentation

TypeDescription
User DocumentationManuals, guides, tutorials for end-users
Technical DocumentationSystem architecture, ER diagrams, coding standards
Process DocumentationWorkflow charts, standard operating procedures (SOPs)
Testing DocumentationTest plans, test cases, bug reports, QA reports

Tip: Good documentation reduces errors, improves maintenance, and helps new team members understand the system quickly.

Implementation and Development Processes

Implementation is the deployment of a system into a live environment, while development involves coding and constructing the system.

Implementation Approaches

1- Parallel Implementation

  • Old and new systems run simultaneously until the new system is stable.
  • Advantage: Low risk; Disadvantage: Costly.

2- Direct Cutover

  • Old system is completely replaced by the new system.
  • Advantage: Quick; Disadvantage: High risk.

3 - Pilot Implementation

  • New system tested in a limited environment before full rollout.

4 - Phased Implementation

  • System is deployed module by module.
  • Advantage: Less risk, easier problem detection.

Development Methodologies

  • Waterfall Model: Sequential, well-structured approach.
  • Agile Model: Iterative, adaptive development with user feedback.
  • Rapid Application Development (RAD): Focus on quick prototyping and iterative delivery.

Hardware and Software Selection Criteria

Choosing the right hardware and software ensures the system performs efficiently and meets business needs.

Hardware Selection Criteria

  • Processing power (CPU, GPU for intensive operations)
  • Memory and storage capacity
  • Reliability and scalability
  • Compatibility with existing systems
  • Cost and energy efficiency

Software Selection Criteria

  • Functional suitability for business processes
  • User-friendliness and learning curve
  • Integration capabilities with other software
  • Vendor support and maintenance
  • Security and compliance features
  • Cost of licensing and updates

Example: For an ERP system, servers must handle multiple users, and software should integrate with CRM, accounting, and inventory modules.

System Maintenance and Support

System maintenance ensures the system continues to function efficiently after deployment. It includes corrective, adaptive, perfective, and preventive maintenance.

Types of Maintenance

TypePurposeExample
Corrective MaintenanceFix bugs and errorsPatching login failures
Adaptive MaintenanceAdapt system to new environmentsUpgrading to new OS or database
Perfective MaintenanceImprove performance or add featuresAdding a new reporting module
Preventive MaintenancePrevent future issuesRegular system audits, backups, and updates

Support Activities

  • User training and helpdesk services
  • Performance monitoring and optimization
  • Updating documentation with changes

Tip: Proper maintenance increases system lifespan, reduces downtime, and improves user satisfaction.


Summary Table

AspectKey PointsExample / Tools
System Testing & QAUnit, integration, system, UAT, performance, security testingSelenium, JMeter, LoadRunner
DocumentationUser, technical, process, testingUser manuals, ER diagrams, SOPs
Implementation & DevelopmentParallel, direct, pilot, phased; Waterfall, Agile, RADERP, CRM, online platforms
Hardware & Software SelectionCPU, memory, storage; software integration, usability, costServers, Oracle DB, SAP, Microsoft 365
Maintenance & SupportCorrective, adaptive, perfective, preventive; user trainingSystem updates, helpdesk, monitoring tools

Information systems are vital for business operations, but they are vulnerable to security threats, errors, and failures. Implementing security controls, auditing, and disaster recovery planning ensures data integrity, confidentiality, and business continuity.

Security and Auditing of Information Systems

Security of Information Systems ensures protection against unauthorized access, misuse, or damage.
Auditing of Information Systems is the process of evaluating and verifying the effectiveness of controls and security mechanisms.

Key Objectives

  • Safeguard organizational data and resources.
  • Ensure compliance with laws and regulatory requirements.
  • Detect and prevent fraud, errors, and security breaches.
  • Evaluate efficiency and effectiveness of system operations.
  • Maintain trust and accountability for stakeholders.

Objectives and Techniques of Information System Controls

Information system controls are measures to manage risks and secure systems.

Objectives of IS Controls

ObjectiveDescription
Preventive ControlStop security breaches or errors before they occur.
Detective ControlIdentify and report errors or security violations.
Corrective ControlRectify errors or restore systems after a breach.
Directive ControlEstablish policies and procedures to guide system usage.

Techniques of IS Controls

TechniquePurposeExample
Authentication & AuthorizationVerify user identity and access rightsPasswords, biometrics, role-based access
EncryptionProtect data in transit and at restSSL/TLS, AES encryption
Firewalls & Intrusion DetectionPrevent unauthorized network accessCisco firewall, Snort IDS
Backup & Recovery ProceduresEnsure data restoration after lossCloud backups, RAID storage
Audit TrailsTrack system activity for accountabilitySystem logs, transaction logs

Tip: Explain controls with real business examples like banking, e-commerce, or ERP systems.

Auditing Information Systems

Information System Auditing evaluates controls, security, and compliance.

Key Steps in IS Auditing

  1. Planning & Risk Assessment - Identify critical systems, data, and potential threats.
  2. Control Evaluation - Assess effectiveness of preventive, detective, and corrective controls.
  3. Testing & Verification - Test system functionality, security, and data accuracy.
  4. Reporting & Recommendations - Highlight vulnerabilities and suggest improvements.

Types of IS Audits

  • Internal Audit: Conducted by in-house IT or audit team.
  • External Audit: Conducted by third-party auditors for compliance or certification.
  • Compliance Audit: Ensure adherence to legal and regulatory frameworks (e.g., GDPR, ISO 27001).

Example: Auditing ERP systems to ensure inventory, finance, and payroll data accuracy and security.

Disaster Recovery and Business Process Continuity Planning

Even with strong controls, systems may fail due to natural disasters, cyber-attacks, or human errors. Planning ensures business operations continue with minimal disruption.

Disaster Recovery (DR)

  • Objective: Restore IT systems and data quickly after an incident.

Key Components

  • Backup and replication of critical data
  • Redundant servers and storage
  • DR site (hot, warm, or cold site)
  • Recovery Time Objective (RTO) and Recovery Point Objective (RPO)

Business Continuity Planning (BCP)

  • Objective: Ensure critical business processes continue during and after a disaster.

Key Steps

  1. Risk assessment and business impact analysis (BIA)
  2. Identify critical processes and dependencies
  3. Develop contingency and communication plans
  4. Conduct regular drills and testing

Example: Banks maintain real-time backup at multiple data centers and BCP to handle system outages.

Summary Table

TopicKey PointsExample / Tools
Security of ISProtect against unauthorized access, misuse, errorsFirewalls, encryption, authentication
IS ControlsPreventive, detective, corrective, directivePasswords, audit trails, backup systems
Auditing ISInternal, external, compliance auditsISO 27001 audits, SOC reports, system logs
Disaster RecoveryRestore systems and data quicklyDR sites, cloud backups, RTO/RPO planning
Business ContinuityMaintain critical business processesBCP plans, drills, contingency procedures

Exam Tips

  1. Explain controls with examples from banking, ERP, or e-commerce systems.
  2. Draw audit flowcharts and DR/BCP frameworks for visual clarity.
  3. Highlight difference between DR and BCP.
  4. Emphasize regulatory compliance and security standards like ISO 27001.