Information Systems, Development Models & Feasibility
Transaction Processing Systems (TPS)
- Computerized systems that capture, process, store, and retrieve the high-volume, routine, day-to-day transactions of an organization
• Examples: sales orders, payroll, inventory receipts, banking deposits
• Serve operational-level users (front-line clerks, cashiers, shop-floor staff)
• Emphasize speed, accuracy, reliability, and data integrity; failures can halt core operations
• Foundation layer for higher-level information systems—data generated here feed MIS, DSS, BI, etc.
• Ethical/practical implication: data privacy and security are critical because TPS handle personally identifiable information (PII) and financial data.
- Provide routine summary, exception, and ad-hoc reports that aid planning, controlling, and decision-making
• Target user group: middle management
• Transform raw TPS data into aggregated metrics (e.g., weekly sales by region, inventory reorder alerts)
• Operate on structured problems with well-defined procedures
• Significance: bridge between operational detail (TPS) and strategic insight (DSS/ESS)
• Typical outputs: dashboards, scheduled PDFs, email alerts
• Depend heavily on reporting cycles; latency is acceptable (daily/weekly) compared to real-time needs in TPS.
Decision Support Systems (DSS)
- Combine internal databases with analytical models, optimization algorithms, or data-mining tools to support semi-structured or unstructured managerial decisions
• Users: analysts, senior/middle managers
• Capabilities: what-if analysis, goal seeking, forecasting, Monte-Carlo simulation, OLAP cube slicing
• Examples: supply-chain network design, loan-portfolio risk analysis
• Real-world relevance: enhances evidence-based decision culture; can uncover hidden patterns but may introduce bias if models are poorly validated
• Ethical dimension: transparency of algorithms is vital to maintain trust.
Executive Support Systems (ESS)
- High-level information systems that present critical success factors (CSFs) and key performance indicators (KPIs) through advanced graphics and communication tools
• Users: C-suite & strategic planners
• Emphasize visualization (heat maps, interactive scorecards) and quick drill-down
• Focus on long-term trends, competitor intelligence, macro-economic variables
• Example scenario: CEO views real-time global sales versus strategic plan on tablet during board meeting
• Success relies on data accuracy from TPS/MIS layers; any inconsistency propagates upward.
- Computer systems that map, model, query, and analyze large volumes of location-tagged data inside a single database
• Provide facilities for visualization (layered maps), scenario simulation, and spatial decision-making
• Typical uses: urban planning, logistics routing, disaster management, precision agriculture
• Integrate disparate datasets—satellite imagery, census data, IoT sensors—to develop powerful, location-aware solutions
• Advanced functions: heat-map generation, shortest-path algorithms, spatial interpolation
• Ethical concerns: surveillance, geoprivacy, equitable resource allocation.
Knowledge Management Systems (KMS)
- Practices and technologies that identify, create, represent, distribute, and enable adoption of organizational knowledge
• Knowledge types: tacit (in people’s heads) vs. explicit (documents, procedures)
• Tools: intranets, expertise locators, wiki platforms, lessons-learned repositories
• Aim to prevent “brain drain,” foster innovation, shorten problem-solving cycles
• Success factors: supportive culture, incentives for sharing, taxonomy governance
• Connections to DSS: captured insights can be input for future analytical models.
Content Management Systems (CMS)
- Computer applications that allow multiple users to create, edit, manage, and publish digital content collaboratively
• Core features: version control, workflow approval, format management, indexing, search & retrieval
• Web CMS examples: WordPress, Drupal, Joomla
• Architectural principle: strict separation of content and presentation to allow multi-channel delivery (web, mobile, print)
• Use cases: corporate websites, e-learning portals, digital asset libraries
• Security implication: role-based access to prevent accidental/unauthorized edits.
Enterprise Resource Planning (ERP) Systems
- Integrated process-management suites that unify core back-office functions across departments
• Modules: product planning, procurement, manufacturing, inventory, sales, CRM, HR, finance
• Provide a single source of truth; reduce data redundancy and manual reconciliation
• Example vendors: SAP, Oracle, Microsoft Dynamics
• Implementation challenges: business-process re-engineering, change management, high TCO
• Ethical/practical implication: tight data integration raises need for robust access control and compliance (e.g., SOX, GDPR).
Expert Systems
- Applications that embed human expert knowledge into a rule-based inference engine to deliver advice to non-experts
• Core components
– Knowledge Base: domain facts, heuristics, production rules (IF–THEN)
– Inference Engine: applies reasoning (forward/backward chaining)
– User Interface: allows queries & explanations
• Development role: Knowledge-engineer interviews SME to codify expertise
• Example: medical diagnosis system suggesting treatments
• Strengths: consistency, availability 24/7, training aid
• Limitations: brittle outside encoded domain, knowledge acquisition bottleneck.
Smart Systems
- Systems capable of sensing, actuating, analyzing, and controlling to make adaptive decisions in near real-time
• Embedded with sensors/actuators; operate on closed-loop control principles
• Attributes: autonomy, energy efficiency, network connectivity (IoT)
• Application domains: smart grids, autonomous vehicles, intelligent factories
• Workflow: data acquisition → predictive/diagnostic analytics → decision → actuation
• Ethical concerns: safety, algorithmic accountability, cybersecurity of connected devices.
Software Development Process Models
Waterfall Model
- Sequential, linear life-cycle model introduced by Dr. Winston W. Royce (1970)
• Phases (in order): Feasibility Study → Requirement Analysis → System Design → Implementation → Testing → Deployment → Maintenance
• Each phase must finish before the next begins; deliverables “flow” downward like a waterfall
• Best for stable, well-understood requirements
• Advantages: simplicity, clear milestones, ease of management
• Disadvantages: inflexible, late visibility of final product, idle team members, poor for changing requirements
• Real-world note: pure waterfall is rare; many firms follow modified or “waterfall-with-feedback” variants.
Spiral Model
- Combines iterative prototyping with systematic aspects of waterfall in a risk-driven spiral
• Each loop (spiral) includes: objectives setting → risk assessment & reduction → development & test → planning next iteration
• Suitable for projects with medium-to-high risk, complex or evolving requirements
• Advantages: strong risk mitigation, customer feedback each cycle, design flexibility
• Disadvantages: process complexity, higher cost, unsuitable for small/simple projects.
Agile Model
- Umbrella term for iterative, incremental frameworks (Scrum, XP, Kanban, etc.)
• Key features: customer collaboration, continuous delivery, adaptability, cross-functional teams
• Work divided into time-boxed iterations/sprints; each produces a potentially shippable increment
• Suitable for both fixed or changing requirements
• Advantages: high flexibility, faster delivery, improved quality via continuous testing
• Disadvantages: requires active stakeholder involvement, difficult to predict schedule/budget precisely, may be costlier for large dispersed teams.
Prototyping
- Building a quick, partial implementation (prototype) to demonstrate functionality, gather user feedback, and refine requirements
• Types: throw-away (exploratory) vs. evolutionary (grows into final system)
• Benefits: clarifies vague requirements, enhances user involvement, reduces overall risk
• Costs: added time & expense, not ideal for every project (e.g., safety-critical with strict specs).
Rapid Application Development (RAD)
- Parallel development of modular prototypes that are later integrated for rapid delivery
• Emphasizes component reusability, visual tools, and time-boxed cycles
• Advantages: faster “go-live,” reduced failure risk, higher user satisfaction
• Disadvantages: demands highly skilled staff, not optimal for large-scale systems.
System Development Methodologies
- Structured Methodology: sequential, well-defined guidelines (often aligned with waterfall)
- Object-Oriented Methodology: models the system as interacting objects; promotes reusability and maintainability
- Choice depends on project size, complexity, and organizational culture.
Preliminary Investigation & Feasibility Study
- First stage of the System Development Life Cycle (SDLC)
- Consists of two phases:
• Problem Definition: preliminary survey to identify scope & boundaries
• Feasibility Study: evaluate practicality & benefits of the proposed system from both developer and user perspectives.
Feasibility Dimensions
- Technical Feasibility
• Do required technologies exist?
• Developer expertise and resource availability? - Economic Feasibility
• Cost-benefit analysis: do projected benefits justify development & operational costs? - Operational Feasibility
• Will end-users accept and effectively use the system?
• Assess resistance, training needs, cultural fit - Organizational Feasibility
• Alignment with organizational strategy, goals, and structures
- Outcome: formal feasibility report; project proceeds only if approved.
Requirement Analysis
- Systematic study of user needs to define functional and non-functional requirements for the new system
• Functional Requirements: services the system must provide, interactions, data transformations
• Non-Functional Requirements: performance, security, usability, reliability, compliance, scalability
• Purpose: define problem domain boundaries, detect conflicts, and provide baseline for design & validation
• Tools/Techniques: interviews, questionnaires, use cases, user stories, observation, document analysis
• Business System Options (BSO): alternative high-level solution approaches evaluated before detailed design.