Systems Analysis and Design chapter 5 (1)

Systems Analysis and Design 11th Edition - Chapter 11 - Managing Systems Implementation

• Chapter Objectives: Explain the importance of software quality assurance and software engineering, describe application development methods (structured, object-oriented, and agile), draw a structure chart showing top-down design, modular design, cohesion, and coupling, explain the coding process, explain unit, integration, and system testing, differentiate between program, system, operations, and user documentation, list the main steps in system installation and evaluation, develop training plans for various user groups and compare training options, describe data conversion and changeover methods, explain post-implementation evaluation and the final report to management

• Software Quality Assurance: Companies are intensely concerned with product and service quality. The objective is to avoid problems or identify them as soon as possible. Poor quality can result from inaccurate requirements, design problems, coding errors, and ineffective testing.

• Software Quality Assurance (Cont. 1): Disciplined application of engineering principles to application creation. The Software Engineering Institute (SEI) at Carnegie Mellon University provides quality standards and procedures for developers and systems analysts. The Capability Maturity Model (CMM) aims to improve software quality, reduce development time, and costs.

• Software Quality Assurance (Cont. 2): Capability Maturity Model Integration (CMMI) tracks organizational processes, using five maturity levels (increasingly controlled and optimized). Process improvement strategies are defined and used at each level.

• Software Quality Assurance (Cont. 3): International Organization for Standardization (ISO) establishes globally recognized quality standards for products and services. ISO 9000-3:2004 provides quality assurance methodologies for developing and maintaining software.

• Overview of Application Development: The process of constructing programs that serve as the fundamental blocks of the information system. Popular methodologies include structured analysis, object-oriented (O-O) analysis, and agile methods. The objective is translating the design into program and code modules.

• Review the Systems Design: Tasks involved include breaking down complex business operations, creating data flow diagrams (DFDs), developing an object-oriented model, selecting a development strategy, designing the user interface, creating entity-relationship diagrams (ERDs), and considering overall system architecture.

• Application Development Tasks: Traditional methodologies establish an overall strategy and design, code, test, and document individual modules. Agile methods use an iterative approach of planning, designing, coding, and testing.

• Overview of Application Development (Cont. 3): Agile methods (like Extreme Programming) create systems through an iterative process of planning, designing, coding, and testing. Simplified models like Extreme Programming (XP) emphasize iteration.

• Systems Development Tools: Tools include entity-relationship diagrams to show interactions between system entities/objects, flowcharts to represent logical rules, pseudocode to describe program actions, and decision tables/trees for business logic modeling.

• Sample of a Sales Promotion Policy: Shows an example of a policy with corresponding pseudocode. The example illustrates logical rules for customer discounts and bonus coupons.

• Project Management: Assists with monitoring and controlling development efforts, including activities from planning to documentation.

• Structured Application Development - Structure Charts: Illustrate modular program code and relationships among modules. Modules are rectangles. Control modules are higher-level, subordinate are lower-level. Reusable code modules that can be invoked from multiple points are included in the chart.

• Structured Application Development - Data and Control Couples: Data couples are shown as arrows with empty circles, illustrating data transfer between modules. Control couples use filled circles to indicate status flags.

• Structured Application Development - Cohesion and Coupling: Cohesion measures a module's scope and characteristics, with a higher degree of cohesion for a module that performs a single function. Coupling describes interdependence among modules (loosely coupled modules are easier to maintain and modify).

• Structured Application Development-Testing: Includes unit testing (individual program/module testing), integration testing (two or more programs that depend on each other) and system testing (final test of all programs and verification of system performance and functionality). System testing also involves the evaluation of documentation and user instructions.

• Structured Application Development - Additional Considerations: Includes stub testing (simulating program outcomes), a test plan created during the systems design phase.

• Documentation: Program documentation describes inputs, outputs, and the logic of all program modules. The process starts in systems analysis and continues through implementation. Defect tracking tools/software document and track program defects, code changes, and patches; online documentation provides help when encountering problems; system documentation describes functions and implementation; operations documentation covers processing and output; user documentation includes instructions for users.

• Online Documentation: Examples like the Cisco Support Community provide immediate help for questions and problem resolution.

• Documentation - (Cont.): Sample pages from user manuals demonstrate how to add new tasks to the system, illustrating the use of inputs and information in forms/screens.

• Management Approval: Post-system testing, the results are presented to management. Documentation status is updated and input from users is summarized. Time schedules, cost estimates, and staffing requirements are provided for system transition to full operation

• System Installation and Evaluation: Establishing a separate operational and test environment, training users, managers, and staff, data conversion, changeover, post-implementation evaluation, and a final management report are key components of this phase.

• Operational and Test Environments: A test environment is distinct from a production environment for software development work. Tests are performed in the test environment prior to implementing the new system in the operational area.

• Training: Identifying who needs training, the type of training required, and the selection of program participants, is important. Training topics (specific to users, managers, and IT staff) and training methods (like vendor training, webinars, podcasts, tutorials, and outside training) are presented. Training should address all related processes, including learning and reliance on past training.

• Data Conversion: Existing data is loaded into a new system. Data conversion strategies such as automation, ASCII or ODBC (Open Database Connectivity) are introduced. Input controls and secure practices are needed to protect data integrity.

• System Changeover: Process of transitioning to a new system. Methods include direct cutover, parallel operation, pilot operation, and phased operation. Factors like cost and risk are considered during the changeover process.

• Post-Implementation Evaluation: Evaluates the system's quality. Focuses on accuracy, completeness, timeliness of data, and factors like user satisfaction, security, and performance.

• Post-Implementation Tasks (Cont.1): Assesses training effectiveness, the accuracy of cost-benefit estimates and schedules. Additional methods of evaluating the system are explored (interviewing personnel, observing operations, reading documentation materials, etc.).

• Post-implementation Tasks (Cont.2): Sample user evaluation forms illustrate the numerical scale for easy tabulation of results and open-ended comment/suggestion options/spaces.

• Chapter Summary (Cont.2 ): Provides a summary of the various tasks involved during the implementation phase (programming, testing, documentation, system changeover, training aspects, etc.

• Chapter Summary (Cont.3 ): Training should be provided to all new system users, and adequate documentation is needed. Data conversion is often required when implementing a new system

• Chapter Summary (Cont.4 ): A post-implementation evaluation and the required management report are included in the system implementation phase; documentation for the entire process is included.