INTRODUCTION TO SYSTEMS ANALYSIS AND DESIGN Nantes, Mark F. BSA ACCO 2063 Tutorial 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. Information technology (IT) refers to the combination of hardware, software, and services that people use to manage, communicate, and share information. The Impact of Information Technlogy The Future Three issues that will shape the future: Changes in world Changes in technology Changes in client demand The Impact of Information Technlogy Systems Development Business information systems are developed by people who are technically qualified, business-oriented, and highly motivated. Successful developers also must be good communicators with strong analytical and critical thinking skills. An information system combines information technology, people, and data to support business requirements. The Impact of Information Technlogy Systems Analysis and Design Systems analysis and design is a stepby-step process for developing highquality information systems. Data Analysts plan, develop, and maintain information systems. The Impact of Information Technlogy Who develops Information Systems? Traditionally, a company either developed its own information systems, called in-house applications, or purchased systems called software packages from outside vendors. 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. Every system requires input data. 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. An information system has five key components: hardware, software, data, processes, and people. Information System Components Hardware It is physical layer of the information system. Moore’s Law - the number of transistors on an integrated circuit would double about every 24 months. It has remained valid for more than 50 years. Software Information System Components It refers to the programs that control the hardware and produce the desired information or results. System software manages the hardware components, which can include a single workstation or a global network with many thousands of clients. Application software consists of programs that support day-to-day business functions and provide users with the information they require. Enterprise applications, include order processing systems, payroll systems, and company communications networks. Information System Components Software A horizontal system is a system, such as an inventory or payroll application, that can be adapted for use in many different types of companies. A vertical system is designed to meet the unique requirements of a specific business or industry, such as a Web-based retailer, a medical practice, or a video chain. When planning an information system, a company must consider how a new system will interface with older systems, which are called legacy systems. Information System Components Data An information system can store data in various locations, called tables. Linked tables work together to supply different data items to the screen form. Processes It describe the tasks and business functions that users, managers, and IT staff members perform to achieve specific results. People Stakeholders are people who have interest in information system. Users (end users) inside & outside the company who will interact with the system. Understand the Business Systems analysts use a process called business process modeling to represent company operations and information needs. It requires a business profile and a series of models that document business processes. . A business profile is an A business process is a A business process model overview of a company’s specific set of (BPM) graphically displays mission, functions, transactions, events, and one or more business organization, products, results that can be processes, such as services, customers, handling an airline described and suppliers, competitors, documented. reservation, filling a product constraints, and future order, or updating a direction customer account. Business process modeling notation (BPMN) includes various shapes and symbols to represent events, processes, and workflows. Understand the Business New Kinds of Companies At the other end of the The newest kind of company is the Product-oriented firms scale are traditional firms, manufactured computers, routers, Internet-dependent firm, often sometimes called brickdescribed as a dot-com (.com) or the microchips whereas and-mortar companies company because its primary business service-oriented companies because they conduct depends on the Internet rather than a included vendors, software business primarily from developers, and service providers. traditional business channel. physical locations. Impact of the Internet Internet-based commerce is called e-commerce (electronic commerce) or I-commerce (Internet commerce). E-commerce includes two main sectors: B2C (business-to-consumer) and B2B (business-tobusiness). B2C B2B electronic data interchange (EDI) extensible markup language (XML) supply chain management (SCM), or supplier relationship management (SRM). Business Information System In the past, IT managers divided systems into categories based on the user group the system served. Categories are: Office systems Operational systems Decision support systems Executive information systems Business Information System Identify a system by its functions and features rather than by its users. (1) Enterprise Computing refers to information systems that support company-wide operations and data management requirements. (2) Transaction Processing (TP) process data generated by day-to-day business operations. TP systems typically involve large amounts of Enterprise resource planning (ERP) systems provide data and are mission-critical systems because cost-effective support for users and managers the enterprise cannot function without them. throughout the company. It is efficient because they process a set of Many hardware and software vendors target the transaction-related commands as a group rather enterprise computing market and offer a wide array than individually. of products and services. Business Information System (3) Business Support systems provide job-related information support to users at all levels of a company. Decision support helps users make decisions by creating a computer model and applying a set of variables by what-if scenarios. Companies soon realized that computers also could (4) Knowledge Management produce valuable information. The new systems were called management information systems Knowledge management systems are called (MIS) because managers were the primary users. expert systems because they simulate human reasoning by combining a knowledge base and The newest development in data acquisition is inference rules that determine how the called radio frequency identification (RFID) knowledge is applied. technology, which uses high-frequency radio waves to track physical objects. Fuzzy logic allows inferences to be drawn from imprecise relationships. Business Information System (5) User Productivity Systems (6) Information Systems Integration Companies provide employees at all levels with technology that improves productivity. Most large companies require systems that combine transaction processing, business support, knowledge management, and user productivity features. User productivity systems also include groupware. Groupware programs run on a company intranet and enable users to share data, collaborate on projects, and work in teams. What Information Do Users Need? Top Managers Middle Managers and Knowledge Workers Top Managers develop long-range plans, called Middle managers provide strategic plans, which direction, necessary define the company’s resources, and performance overall mission and goals.feedback to supervisors and team leaders. Knowledge workers include professional staff members Supervisors and Team Leaders Supervisors, often called team leaders, oversee operational employees and carry out day-to-day functions. Operational Employees Operational employees include users who rely on TP systems to enter and receive data they need to perform their jobs. System Development Tools Modeling produces a graphical representation of a concept or process that systems developers can analyze, test, and modify. Business model, or requirements model describes the information that a system must provide. Data model describes data structures and design. Object model describes objects, which combine data and processes. Network model describes the design and protocols of telecommunications links. Process model describes the logic that programmers use to write code modules. System Development Tools Prototyping tests system concepts and provides an opportunity to examine input, output, and user interfaces before final decisions are made. A prototype is an early working version of an information system. It speeds up the development process significantly. A possible con is that important decisions might be made too early, before business or IT issues are understood thoroughly. It can be an extremely valuable tool. System Development Tools Computer-aided systems engineering (CASE), also called computer-aided software engineering, is a technique that uses powerful software, called CASE tools, to help systems analysts develop and maintain information systems. CASE tools provide an overall framework for systems development and support a wide variety of design methodologies, including structured analysis and objectoriented analysis. It can generate program code, which speeds the implementation process Systems Development Methods Structured analysis uses a series of phases, called the systems development life cycle (SDLC), to plan, analyze, design, implement, and support an information system. It is based on an overall plan,so it is called a predictive approach. It uses a set of process models to describe a system graphically. Process-centered tecnique, it focuses on processes that transform data into useful information.I In the waterfall model, the result of each phase is called a deliverable, or end product, which flows into the next phase. Systems Development Methods Some analysts see a 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. SDLC model: 1. Planning 2. Analysis 3. Design 4. Implementation 5. Support and security Systems Development Methods Object-Oriented Analysis (O-O) O-O analysis combines data and the processes that act on the data into things called object. An object is a member of a class (collection of similar objects). Objects possess characteristics called properties (inherits from its class or possesses on its own). In O-O design, built-in processes called methods can change an object’s properties. A message requests specific behavior or information from another object. O-O usually follow a series of analysis and design phases that are similar to the SDLC and phases tend to be more interactive. Systems Development Methods Agile Methods are the newest development. An agile approach emphasizes continuous feedback, and each incremental step is affected by what was learned in the prior steps. The notion of iterative development can be traced back to Japanese auto firms that were able to boost productivity by using a flexible manufacturing system. Typically use a spiral model, which represents a series of iterations, or revisions, based on user feedback. Agile process determines the end result. Systems Development Methods By their nature, agile methods can allow developers to be much more flexible and responsive, but can be riskier than more traditional methods. A cons of agile methods can include weak documentation, blurred lines of accountability, and too little emphasis on the larger business picture. Other Systems Development Methods: Joint Application Development (JAD) and Rapid Application Development (RAD). Rational Unified Process (RUP®). Microsoft Solutions Framework (MSF) Systems Development Guidelines Develop a Plan. Involve Users and Listen Carefully to Them. Use Project Management Tools and Techniques. Develop Accurate Cost and Benefit Information. Remain Flexible. The Information Technology Department Director Information Technlogy Application Development Systems Support and Security User Support Database Administration Network Administration Web Support Quality Assurance (QA) The Systems Analyst Responsibilities Translate business requirements into IT projects. Knowledge, Skills, and Education Needs technical knowledge, oral and written communication skills, an understanding of business operations, and critical thinking skills. Certifications Important credentials. Career Opportunities Job titles, Company organization, Company size, Corporate culture, Salary, Location and Future growth REFERENCE: Shelly, G. B., & Rosenblatt, H. J. (2011, March 7). Systems Analysis and Design (SAM 2010 Compatible Products) (9th ed.). Course Technology.
