Chapter 01_2024.ppt

Systems Analysis and Design 8 Edition th Chapter 1 Introduction to Systems Analysis and Design Introduction Companies use information as a weapon in the battle to increase productivity, deliver quality products and services, maintain customer loyalty, and make sound decis...

Systems Analysis and Design 8 Edition th Chapter 1 Introduction to Systems Analysis and Design Introduction Companies use information as a weapon in the battle to increase productivity, deliver quality products and services, maintain customer loyalty, and make sound decisions. Information technology can mean the difference between success and failure 2 The Impact of Information Technology Information Technology (IT) – Combination of hardware and software products and services that companies use to manage, access, communicate, and share information The Future of IT – Will see robust growth for at least a decade – The greatest need will be for systems analysts, network administrators, data communications analysts, and software engineers 3 The Impact of Information Technology The Role of Systems Analysis and Design – Systems Analysis and Design Step-by-step process for developing high- quality information systems – Systems Analyst Plan, develop, and maintain information systems 4  The Impact of Information Technology Who develops Information Systems? –In-house applications –Software packages –Internet-based application services ? –Outsourcing –Custom solutions –Enterprise-wide software strategies? How versus What: Know what the system must do before how to implement the new system. 5 Information System Components A system is a set of related components that produces specific results A Mission-critical system is one that is vital to a company’s operations Data consists of basic facts that are the system’s raw material Information is data that has been transformed into output that is valuable to users Information systems have five key components: hardware, software, data, processes, and people 6 Information System Components Hardware – Is the physical layer of the information system – Moore’s Law Software – System software – Application software – Enterprise applications 7 Information System Components Software – Horizontal system – Vertical system – Legacy systems Data – Tables store data – By linking the tables, the system can extract specific information 8 Information System Components Processes – Describe the tasks and business functions that users, managers, and IT staff members perform to achieve specific results People – Stakeholders – Users, or end users 9 Understanding The Business Business Process Modeling – To represent a company’s operations and information needs Business Profile – Describes a company’s overall functions Business Models – Business model – Business process – Business process reengineering (BPR) 10 11 12 Understanding The Business New Kinds of Companies – Production-oriented – Service-oriented – Internet-dependent – Dot-com (.com) – Brick-and-mortar 13 Impact of the Internet E-Commerce or I-Commerce B2C (Business-to-Consumer) B2B (Business-to-Business) – EDI Electronic Data Interchange – Extensible markup language (XML) Standard protocols, universal availability, low cost – Supplier relationship management (SRM) Supplier collaboration over the web to add efficiencies and reduce costs 14 Impact of the Internet Web-Based System Development – WebSphere –.NET – Web services – Internet-based systems involve various hardware and software designs 15 How Business Uses Information Systems In the past, IT managers divided systems into categories based on the user group the system served – Office systems – Operational systems – Decision support systems – Executive information systems 16 How Business Uses Information Systems Enterprise computing systems – Support company- wide operations and data management requirements – Enterprise resource planning (ERP) – Many hardware and software vendors target the enterprise computing market 17 How Business Uses Information Systems Transaction processing systems – Involve large amounts of data and are mission-critical systems – Efficient because they process a set of transaction-related commands as a group rather than individually 18 How Business Uses Information Systems Business support systems – Provide job-related information to users at all levels of a company – Management information systems (MIS) – Radio frequency identification (RFID) – What-if 19 How Business Uses Information Systems Knowledge management systems – Called expert systems – Simulate human reasoning by combining a knowledge base and inference rules – Many knowledge management systems use a technique called fuzzy logic 20 How Business Uses Information Systems User productivity systems – Technology that improves productivity – Groupware Information systems integration – Most large companies require systems that combine transaction processing, business support, knowledge management, and user productivity features 21 Information System Users and Their Needs 22 Systems Development Tools Modeling – Business model – Requirements model – Data model – Object model – Network model – Process model 23 Systems Development Tools Prototyping – Prototype – Speeds up the development process significantly – Important decisions might be made too early, before business or IT issues are thoroughly understood – Can be an extremely valuable tool 24 Systems Development Tools Computer-Aided Systems Engineering (CASE) Tools – Also called computer-aided software engineering – CASE tools – Can generate program code, which speeds the implementation process 25 Overview of Systems Development Methods Structured Analysis – Systems development life cycle (SDLC) – Predictive approach – Uses a set of process models to describe a system graphically – Process-centered technique – Waterfall model 26 Overview of Systems Development Methods Structured Analysis – Deliverable or end product – Disadvantage in the built-in structure of the SDLC, because the waterfall model does not emphasize interactivity among the phases – This criticism can be valid if the SDLC phases are followed too rigidly – Adjacent phases usually interact 27 Overview of Systems Development Methods Structured Analysis – The SDLC model usually includes five steps Systems planning Systems analysis Systems design Systems implementation Systems support and security 28 Overview of Systems Development Methods Structured Analysis – Systems Planning Systems planning phase Systems request – begins the process & describes problems or desired changes Purpose of this phase is to perform a preliminary investigation Key part of preliminary investigation is a feasibility study: Update, Replace, or Null Alternative 29 Overview of Systems Development Methods Structured Analysis – Systems Analysis Deliverable is the System requirements document What the system should/must do – Systems Design Deliverable is system design specification Management and user involvement is critical How the system will accomplish what it should do 30 Overview of Systems Development Methods Structured Analysis – Systems Implementation New system is constructed – Systems Support and Security A well-designed system must be secure, reliable, maintainable, and scalable Most information systems need to be updated significantly or replaced after several years of operation 31 Overview of Systems Development Methods Object-oriented Analysis – Combines data & processes that act on the data into things called objects – Object is a member of a class – Objects possess properties – Methods change an object’s properties 32 Overview of Systems Development Methods Object-Oriented Analysis – A message requests specific behavior or information from another object – Usually follow a series of analysis and design phases that are similar to the SDLC – Interactive model 33 Overview of Systems Development Methods Agile Methods (p. 23) – Are the newest development – Emphasizes continuous feedback – Iterative development – Agile community has published the Agile Manifesto – Spiral model 34 Overview of Systems Development Methods Agile Methods – Agile process determines the end result – Other adaptive variations and related methods exist – Two examples are Scrum and Extreme Programming (XP) the entire development process is performed by one cross-functional team – Analysts should understand the pros and cons of any approach before selecting a development method 35 Overview of Systems Development Methods Other Development Methods – Joint application development (JAD) – Rapid application development (RAD) – Might encounter other systems development techniques – Rational Unified Process (RUP®, IBM approach) – Microsoft Solutions Framework (MSF) 36 Systems Development Guidelines Develop a project plan Involve users and listen carefully to them Use project management tools to identify tasks and milestones Develop accurate cost and benefit information Remain flexible 37 Information Technology Department 38 The Systems Analyst Position Responsibilities – Translate business requirements into IT projects Required Skills and Background – Solid technical knowledge, strong oral and written communication skills and analytic ability, and an understanding of business operations and processes Certification – Important credential 39 The Systems Analyst Position Career Opportunities – Job titles (beware “programmer analyst”) – Company organization (how does IT fit in?) – Company size (plusses to both large and small) – Corporate culture (Beliefs, rules, traditions, values and attitudes) – Salary, location, and future growth 40