Systems Analysis & Design – Comprehensive Notes (Lectures 6–8)

System Development Life Cycle (SDLC)

• Definition
  • A step-by-step framework that describes activities & functions every developer performs, regardless of the chosen method.
  • Core phases: Systems Planning → Systems Analysis → Systems Design → Systems Implementation → Systems Support & Security (Maintenance).
• Structured/Waterfall Highlights
  • Time-tested, easy to understand.
  • Each phase produces a deliverable and feeds the next.
  • Interaction among phases (feedback loops) is possible but limited.

SDLC Phase 1 – Systems Planning

• Trigger: formal System Request (reaction to opportunity, problem, directive).
• Goal: conduct Preliminary Investigation & Feasibility Study.
• Key tasks
  • Understand problem/opportunity ⚑ (fishbone diagram optional)
  • Define scope & constraints (MoSCoW list: Must/Should/Could/Won’t Do).
  • Perform fact-finding (interviews, observation, surveys, doc review).
  • Analyze usability, cost, benefit, schedule (Pareto & scatter charts).
  • Evaluate feasibility
  • Operational, Technical, Economic (TCO), Schedule.
  • Prepare recommendation to management.

SDLC Phase 2 – Systems Analysis

• Objectives
  • Understand business requirements & build logical model.
  • Ensure system aligns with corporate culture & user expectations.
• Activities
  • Requirements Modeling – outputs, inputs, processes, performance, controls.
  • Data & Process Modeling – DFDs, data dictionaries.
  • Object Modeling (possible).
  • Deliverable: System Requirements Document.
• Fact-Finding Techniques
  • Interviews (open/closed/range questions).
  • Questionnaires (halo effect, ordering rules).
  • Observation, document review, site visits, brainstorming, sampling.

SDLC Phase 3 – Systems Design

• Goal: create physical model satisfying requirements.
• Decisions: architecture, database, user interface, security, hardware.
• Management & user involvement critical.
• Deliverable: System Design Specification.

SDLC Phase 4 – Systems Implementation

• Construct, code, test, document & install system.
• Includes conversion plan, training, and System Evaluation.
• Deliverable: fully functional & documented information system.

SDLC Phase 5 – Systems Support & Security

• Ongoing maintenance: corrective, adaptive, perfective changes.
• Must ensure security, reliability, maintainability, scalability.

Systems Development Methods

• Structured Analysis – Waterfall (good documentation, time/resources required).
• Object-Oriented (O-O) Analysis – iterative, continuous prototypes, UML.
• Agile / Adaptive Methods – spiral iterations, user feedback, fast change; disadvantage: scope creep, documentation gap.
• Hybrid Choices
  • Choose method based on culture, time-criticality, system modularity, legacy docs.
• Other Techniques
  • JAD – team-based fact finding with users.
  • RAD – compressed life cycle, heavy prototyping.

Modeling Business Operations (BPMN)

• Business Process = set of transactions, events, results.
• BPMN provides standard shapes for events, activities, gateways.
• Organizational elements
  • Pool – external business party/company.
  • Lane – subdivision inside pool (dept., role, system).
• Benefits: common language bridging intention & implementation.

Project Management Essentials

• Success metrics: on time, within budget, meets requirements, satisfies users.
• Project Triangle: Cost ↔ Scope ↔ Time (change one, others shift).
• Planning/Scheduling Steps
  1. Work Breakdown Structure (WBS).
  2. Identify Task Patterns (dependent, concurrent, multiple predecessor/successor).
  3. Calculate Critical Path (PERT/CPM).
• Estimating Duration (PERT weighted average)
  T_E = \frac{B + 4P + W}{6}
• Tools: Gantt (progress bars), PERT/CPM (network diagram).
• Risk Management
  1. Develop plan.
  2. Identify risks.
  3. Qualitative & quantitative analysis.
  4. Create response/contingency plan.
  5. Monitor continuously (risk matrix).

Requirements Modeling (Lecture 6B)

• System Requirement Categories: Outputs, Inputs, Processes, Performance, Controls (or Functional vs Technical).
• Interview Best Practices: pick right people, set objectives, avoid leading Qs.
• Additional Fact-Finding: observation, site visits, surveys, brainstorming, sampling.

Data Flow Diagrams (DFD)

• Purpose: show what system does—flows & storage of data—not program logic.
• Four Symbols (Gane-Sarson / Yourdon)
  • Process (verb phrase, ID).
  • Data Flow (named arrows).
  • Data Store (noun, D1…).
  • External Entity (terminator, noun).
• Rules
  • Process must have at least 1 input & 1 output.
  • No data store ↔ data store or entity ↔ entity flows without a process.
  • No “black holes”, “spontaneous generation”, or “gray holes”.
• Creating a Set of DFDs
  1. Context Diagram – one process (0) + entities.
  2. Level-0 (Diagram 0) – decompose process 0 into major processes & data stores.
  3. Further leveling (1.1, 1.2 …) until functional primitives.
  4. Balancing – parent & child diagrams’ interfaces match.
  5. Rule of 7 ± 2: ≤9 processes or data flows per diagram to avoid overload.

Object-Oriented Analysis & UML (Lecture 6C)

• Fundamental OOP Concepts
  • Abstraction – focus on essential ideas.
  • Encapsulation – hide data, expose methods.
  • Inheritance – subclasses reuse parent attributes/methods.
  • Polymorphism – same message, different behaviors.
• Terminology
  • Class: blueprint of similar objects.
  • Object/Instance: concrete member with attributes & methods.
  • Message: invocation of method.
• UML Diagrams used in Analysis
  • Use Case (starting point) – actors & system boundary.
  • Class Diagram – static structure.
  • Activity, Statechart, Sequence, etc.
• Use Case Relationships
  • <> (mandatory reuse).
  • <> (optional/exception flow).

Development Strategies

• Outsourcing
  • Types: Onshore, Nearshore, Offshore, Crowdsourcing.
  • Pros: cost, speed, focus on core business.
  • Cons: loss of control, dependency, info security risks.
• Self-Sourcing (End-User Dev.)
  • Pros: reduce backlog, flexible.
  • Cons: misuse of resources, poor documentation/security, standards gaps.
  • Mitigation: corporate guidelines, data administration enforcement.
• CASE Tools
  • Automate modeling, ensure rule compliance, maintain repository, track versions.
  • Output: specs, design docs, code skeletons.

E-Commerce Fundamentals (Lecture 7 Part A)

• Definitions
  • E-Business – all Internet-enabled internal & external processes.
  • E-Commerce – buying/selling goods/services online.
• Porter Value Chain & EC: EC can add value, reduce cost, improve ops.
• Advantages vs Disadvantages
  • + Price transparency, global reach, personalized service, admin savings.
  • – Bandwidth limits, security/privacy issues, user acceptance.
• Business Models
  • Merchant, Brokerage, Advertising, Mixed, Infomediary, Subscription.
• Transaction Categories
  • B2C, B2B, C2C, C2B, G2C, G2B, G2G, G2E, plus Intrabusiness EC.

B2C Cycle & Channel Strategies

• Activities: Information Sharing → Ordering → Payment → Fulfillment → Service/Support.
• Sales Channels: store, web, mobile, social.
• Strategies
  • Multichannel (independent); Cross-channel (connected); Omnichannel (integrated).

B2B Models

• Seller-Side Marketplace.
• Buyer-Side Marketplace.
• Exchange/Third-Party Marketplace (vertical/horizontal).
• Trading-Partner Agreements (e-collaboration).

Mobile & Voice Commerce

• m-Commerce uses WAP + handhelds.
• Voice-based uses recognition & TTS.

Supporting Technologies

• Electronic Payment Systems (cards, EFT, EDI).
• Micropayments – accumulate small amounts.
• Digital/Mobile Marketing: apps, in-game, LBS, QR, SMS, search & image ads.
• SEO: keywords, titles, inbound links, quality content.

Social Commerce & Hypersocial Org.

• Social networks influence purchasing; provide buy links & reviews.
• Hypersocial organizations leverage communities for deeper customer engagement.

Enterprise Systems (Lecture 8)

Supply Chain Management (SCM)

• Supply Chain = integrated network (org + suppliers + logistics + brokers).
• SCM functions: procuring materials → transforming → distributing.
• Information/Material/Financial flows; key decisions: location, inventory, production, transportation.
• Electronic Data Interchange (EDI) & Web-based EDI reduce cost, accelerate docs.
• Internet-Enabled SCM benefits: lower info cost, real-time sharing, global partnerships, e-marketplaces.
• CPFR – Collaborative Planning, Forecasting & Replenishment using POS data; reduces inventory & logistics cost.
• Emerging Tech: 3D printing, drones, IoT for visibility & personalization.

Customer Relationship Management (CRM)

• Tracks & organizes customer interactions to improve service & retention.
• Activities: sales automation, order processing, marketing automation, support, knowledge management, personalization.
• Implementations: On-premise vs Web-based (eCRM). Vendor examples: SAP, Oracle, Amdocs.
• Personalization Tools: Internet, data warehouses/marts, data-mining, mobile, Collaborative Filtering (recommendations) – needs large datasets; limited cross-category.

Knowledge Management (KM)

• Converts tacit → explicit knowledge, stores in repository, encourages sharing.
• Tools: Groupware, DBMS, data mining, DSS.
• Benefits: innovation, faster service, revenue gains, employee retention.

Enterprise Resource Planning (ERP)

• Integrated suite tying SCM, CRM, HR, Finance, Manufacturing, etc. via unified database.
• Core Components & Functions
  • Inventory, Supply Chain, Manufacturing, HR, CRM, Purchasing, Accounting, Vendor Integration, Sales, E-Commerce.
• Benefits: real-time integrated data, accuracy, better planning, reduced costs.
• Drawbacks: high cost, complex install, training needs, legacy compatibility.
• Vendors: SAP, Oracle, Sage, Microsoft.

Additional Analytical Tools

• SWOT Analysis – Strengths, Weaknesses, Opportunities, Threats (technical, human, financial resources).
• Fishbone (Ishikawa) Diagram – cause-and-effect, dig for root causes.

Key Formulas & Statistics

• PERT Expected Duration: T_E = \frac{B + 4P + W}{6}
• Pareto Principle: 80 % of problems from 20 % of causes.

Ethical, Philosophical & Practical Implications

• Outsourcing & data security (ethical duty to protect strategic info).
• Personalization vs privacy (data collection must balance user consent).
• Social commerce transparency (reviews, influencer responsibilities).
• Enterprise systems require change management—impact on culture, jobs, training.

Cross-Lecture Connections

• SDLC & Project Management underpin all later topics (EC, ERP, CRM).
• BPMN, DFD, and UML provide multi-view modeling; CASE tools ensure consistency.
• Risk management principles apply equally to outsourcing, ERP rollouts, & e-commerce security.
• Knowledge Management enhances CRM which, in turn, feeds data-driven personalization for e-commerce channels.