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This chapter provides an introduction to the fundamentals of information systems, including the difference between data and information, the role of information systems architecture, and the stakeholders involved in systems development. It also explores the perspectives of data, process, interface, and geography in information systems architecture.
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Introduction • The chapter will address the following questions: • What is the difference between data and information? • What is the the product called an information system? • What are six classes of information system applications and how they interoperate? • What is the role of information systems architecture in systems development? • What are four groups of stakeholders in information systems development and the unique role of the systems analyst in relation to the four groups? • Could you be able to recognize categories of systems users and managers who become stakeholders in systems development?
Introduction • The chapter will address the following questions: • Can you differentiate between a perspective and a view as it relates to information systems architecture? • What are four perspectives of the DATA focus for an information system? • What are four perspectives of the PROCESS focus for an information system? • What are four perspectives of the INTERFACE focus for an information system? • What are four perspectives of the GEOGRAPHY focus for an information system?
A Review of Fundamentals ofInformation Systems • What is the difference between Data and Information? • Data are raw facts about the organization and its business transactions. Most data items have little meaning and use by themselves. • Information is data that has been refined and organized by processing and purposeful intelligence. • Information Systems transform data into useful information. • An information system is an arrangement of people, data, processes, interfaces, and geography that are integrated for the purpose of supporting and improving the day-to-day operations in a business, as well as fulfilling the problem-solving and decision-making information needs of business managers.
A Review of Fundamentals ofInformation Systems • Information technology has significantly expanded the power and potential of most information systems. • Information technology is a contemporary term that describes the combination of computer technology (hardware and software) with telecommunications technology (data, image, and voice networks).
A Review of Fundamentals ofInformation Systems • Transaction Processing Systems • Business transactions are events that serve the mission of the business. • Transaction processing systems are information system applications that capture and process data about (or for) business transactions. They are sometimes called data processing systems.
A Review of Fundamentals ofInformation Systems • Management Information Systems • Management Information Systems supplement transaction processing systems with management reports required to plan, monitor, and control business operations. • A management information system (MIS) is an information system application that provides for management-oriented reporting, usually in a predetermined, fixed format.
A Review of Fundamentals ofInformation Systems • Decision Support Systems • Decision Support Systems are concerned with providing useful information to support the decision process. • A decision support system (DSS) is an information system application that provides its users with decision-oriented information whenever a decision making situation arises. When applied to executive managers, these systems are sometimes called executive information systems. • A DSS is designed to support unstructured decisions.
A Review of Fundamentals ofInformation Systems • Decision Support Systems • A DSS provides one or more of the following types of support to the decision maker: • Identification of problems or decision making opportunities (similar to exception reporting). • Identification of possible solutions or decisions. • Access to information needed to solve a problem or make a decision. • Analysis of possible decisions, or of variables that will impact a decision. Sometimes this is called ‘what if’ analyses. • Simulation of possible solutions and their likely results.
A Review of Fundamentals ofInformation Systems • Decision Support Systems • A DSS can utilize a Data Warehouse. • A data warehouse is a read-only, informational database that is populated with detailed, summary, and exception information that can be accessed by end users and managers with DSS tools that generate a virtually limitless variety of information in support of unstructured decisions.
A Review of Fundamentals ofInformation Systems • Expert Systems • Expert Systems are an extension of the decision support system. • An expert system is an information system application that captures the knowledge and expertise of a problem solver or decision maker, and then simulates the ‘thinking’ of that expert for those who have less expertise. • Expert systems are implemented with artificial intelligence technology, often called expert system shells.
A Review of Fundamentals ofInformation Systems • Office Information Systems • Office Information Systems are concerned with getting all relevant information to all those who need it. • Office information systems support the wide range of business office activities that provide for improved work flow and communications between workers, regardless of whether or not those workers are physically located in an office. • Office information systems may use the following technologies: • Electronic forms technology • Work group technology • Electronic messaging technology • Office automation suite technology • Imaging technology
A Review of Fundamentals ofInformation Systems • Personal and Work Group Information Systems • Personal and Work Group Information Systems typically are built using personal computer technology and software. • Personal information systems are those designed to meet the needs of a single user. They are designed to boost an individual’s productivity. • Work group information systems are those designed to meet the needs of a work group. They are designed to boost the group’s productivity.
A Framework For Information Systems Architecture • What is an Information Systems Architecture? • An information systems architecture provides a unifying framework into which various people with different perspectives can organize and view the fundamental building blocks of information systems. • Stakeholders have different views of the system and each has something “at stake” in determining the success of the system. • Stakeholders can be broadly classified into four groups: • System Owners • System Users • System Designers • System Builders
Perspectives - The People Side of Information Systems • What are Information Workers? • The term information worker (also called knowledge worker) was coined to describe those people whose jobs involve the creation, collection, processing, distribution, and use of information. • System Owners • System owners are an information system's sponsors and chief advocates. They are usually responsible for budgeting the money and time to develop, operate, and maintain the information system. They are also ultimately responsible for the system’s justification and acceptance.
Perspectives - The People Side of Information Systems • System Users • System users are the people who use (and directly benefit from) the information system on a regular basis – capturing, validating, entering, responding to, storing, and exchanging data and information. • There are many classes of system users including: • Internal Users • Clerical and service workers • Technical and professional staff • Knowledge workers are a subset of information workers whose responsibilities are based on a specialized body of knowledge. • Supervisors, middle managers, and executive managers
Perspectives - The People Side of Information Systems • System Users • There are many classes of system users including: (continued) • Remote and Mobile Users • External Users
Perspectives - The People Side of Information Systems • System Designers • System designers translate users' business requirements and constraints into technical solutions. They design the computer files, databases, inputs, outputs, screens, networks, and programs that will meet the system users' requirements. They also integrate the technical solution back into the day-to-day business environment.
Perspectives - The People Side of Information Systems • System Designers • Today’s system designers tend to focus on technical specialties. • Database designers have a DATA focus. • Software engineers and programmers have a PROCESS (or program) focus. • Personal computing specialists and systems integrators usually have an INTERFACE focus. • Network and telecommunications specialists have a GEOGRAPHY focus.
Perspectives - The People Side of Information Systems • System Builders • System builders construct the information system components based upon the design specifications from the system designers. In many cases, the system designer and builder for a component are one and the same. • The applications programmer is the classic example of a system builder.
Perspectives - The People Side of Information Systems • The Role of the System Analyst • For the system owners and users, the analyst typically constructs and validates their views. • For the system designers and builders, the analyst (at the very least) ensures that the technical views are consistent and compatible with the business views.
Building Blocks - Expanding The Information System Framework • There are at least four distinct focuses in a system. • DATA - the raw material used to create useful information. • PROCESSES - the activities (including management) that carry out the mission of the business. • INTERFACES - how the system interacts with people and other systems • GEOGRAPHY - where the data is captured and stored; where the processes happen; where the interfaces happen.
Building Blocks - Expanding The Information System Framework • Building Blocks of Data • Data is the raw material used to produce information. • Goal is to capture and store business data using database technology.
Building Blocks - Expanding The Information System Framework • Building Blocks of Data • System Owners’ View of Data • They are interested in business resources. • Business resources are (1) things that are essential to the system's purpose or mission; or (2) things that must be managed or controlled in order to achieve business goals and objectives.
Building Blocks - Expanding The Information System Framework • Building Blocks of Data • System Users’ View of Data • They are experts about the data that describe the business system. • Only see data in how it is currently implemented or think it should be implemented. • They relate data requirements to systems analysts. • Data requirements are a representation of users' data in terms of entities, attributes, relationships, and rules. Data requirements should be expressed in a format that is independent of the technology that can or will be used to implement the data.
Building Blocks - Expanding The Information System Framework • Building Blocks of Data • System Designers’ View of Data • System designers translate requirements into computer files and databases. • System designers’ view of data consists of data structures, database schemas, file organizations, fields, indexes, and other technology-dependent components. • System designers’ view of data as shown in the data column of the framework is a database schema.
Building Blocks - Expanding The Information System Framework • Building Blocks of Data • System Builders’ View of Data: • System builders are closest to the database technology foundation. • System builders are forced to represent data in very precise and unforgiving languages. • The most commonly encountered database construction language is SQL (Structured Query Language).
Building Blocks - Expanding The Information System Framework • Building Blocks of Processes • PROCESSES deliver the functionality of an information system. • Processes perform the work in a system. • The goal is to automate appropriate processes with software technology.
Building Blocks - Expanding The Information System Framework • Building Blocks of Processes • System Owners’ View of Processes • System owners are interested in the groups of high-level processes called business functions. • Business functions are ongoing activities that support the business. Functions can be decomposed into other functions, and eventually, into discrete processes that do specific tasks. • Historically, most information systems were (or are) function-centered. That meant that the system supported one business function or functional area.
Building Blocks - Expanding The Information System Framework • Building Blocks of Processes • System Owners’ View of Processes (continued) • Today, many single-function information systems are being redesigned as cross-functional systems. • A cross functionalinformation system supports relevant business processes from several business functions without regard to traditional organizational boundaries such as divisions, departments, centers, and offices. • This trend is being driven by total quality management and business process redesign initiatives that are intended to reinvent and streamline the way organizations do business
Building Blocks - Expanding The Information System Framework • Building Blocks of Processes • System Users’ View of Processes • Users see processes in terms of discrete business processes. • Business processes are discrete activities that have inputs and outputs, as well as starting times and stopping times. Some business processes happen repetitively, while others happen occasionally, or even rarely. Business processes may be implemented by people, machines, computers, or a combination of all three. • Specific policies and procedures underlie these business processes. • Policies are a set of rules that apply to a business process. • Procedures are step-by-step instructions and logic for accomplishing a business process.
Building Blocks - Expanding The Information System Framework • Building Blocks of Processes • System Designers’ View of Processes • Is constrained by the limitations of specific technology. • Choice(s) may be limited by a standardized application architecture that specifies which software (and hardware) technologies must be used. • The designers’ view of processes is technical. • The designer tends to focus on an application schema. • An application schema is a model that communicates how selected business processes are, or will be, implemented using the computer and programs.
Building Blocks - Expanding The Information System Framework • Building Blocks of Processes • System Builders’ View of Processes • System builders represent PROCESSES using precise computer programming languages that describe inputs, outputs, logic, and control. • Computer programming languages are used to write applications programs. • Applications programs are language-based, machine-readable representations of what a computer process is supposed to do, or how a computer process is supposed to accomplish its task.
Building Blocks - Expanding The Information System Framework • Building Blocks of Processes • System Builders’ View of Processes (continued) • Some computer programming languages provide an excellent environment for prototyping computer processes. • Prototyping is a technique for quickly building a functioning model of the information system using rapid application development tools (provided with most popular programming languages).
Building Blocks - Expanding The Information System Framework • Building Blocks of Interfaces • There are two critical components to information system Interfaces. • Information systems must provide effective and efficient interfaces to the system’s users. • Information systems must interface effectively and efficiently to other information systems, both within the business, and increasingly with other businesses’ information systems. • Technologies exist to implement interfaces. • Technologies exist that can almost completely eliminate human error or intervention. • Technologies exist for system integration.
Building Blocks - Expanding The Information System Framework • Building Blocks of Interfaces • System Owners’ View of Interfaces • System owners are concerned with costs and benefits of the interfacing solutions that will be developed. • When considering whether or not to sponsor a new information system, the system owners only want to know: • With which business units, customers, and external businesses will the new system interface? • What are the key inputs and outputs with respect to those business units, customers, and external businesses? • Will the system have to interface with any other information systems or services? • Are there any corporate or governmental regulations or policies that may constrain the system interfaces?
Building Blocks - Expanding The Information System Framework • Building Blocks of Interfaces • System Users’ View of Interfaces • System users are most interested in what has come be called the user interface to the system. • The user interface defines how the system users directly interact with the information system to provide inputs and queries, and receive outputs and help. • The explosive growth of personal computers, combined with the popularity of graphical user environments such as Microsoft Windows (for Intel-based PCs) and Apple Macintosh (for Motorola-based PCs) has created a defacto standard – the graphical user interface.
Building Blocks - Expanding The Information System Framework • Building Blocks of Interfaces • System Designers’ View of Interfaces • System designers must be concerned the details of both user and system interfaces. • System designers are concerned with consistency, completeness, and user dialogues of user interfaces. • User dialogues describe how the user moves from screen-to-screen, interacting with the application programs to perform useful work. • System designers view the interface in terms of interface properties, system states, events that change the system states, and responses to events. • Collectively, this is called the interface schema.
Building Blocks - Expanding The Information System Framework • Building Blocks of Interfaces • System Designers’ View of Interfaces (continued) • System designers are concerned with system-to-system interfaces. • System designers have to design the system-to-system interfaces that allow a new information system to transparently interoperate with previously designed systems.
Building Blocks - Expanding The Information System Framework • Building Blocks of Interfaces • System Builders’ View of Interfaces • System builders construct, install, test, and implement both user and system interfaces. • For user interfaces, the technology is usually embedded into the programming language environments used to construct the computer processes. • System interfaces are considerably more complex to construct and may utilize system interfacing technologies such as middleware. • Middleware is a layer of utility software that sits in between applications software and systems software to transparently integrate differing technologies so that they can operate.
Building Blocks - Expanding The Information System Framework • Building Blocks of Geography • Information systems geography describes: • the distribution of DATA, PROCESSES, and INTERFACES (the other building blocks) to appropriate business locations • the movement of data and information between those locations • The inclusion of GEOGRAPHY in the framework is driven by the trend towards distributed computing. • Distributed computing is the decentralization of applications and databases to multiple computers across a computer network.
Building Blocks - Expanding The Information System Framework • Building Blocks of Geography • The most popular application of distributed computing is called client/server computing. • In a client/server computing application, information system building blocks are distributed between ‘client’ personal computers and ‘server’ shared computers. The clients and servers effectively interoperate to share the overall workload.
Building Blocks - Expanding The Information System Framework • Building Blocks of Geography • Distributed computing is being driven by several trends. • Organizations that can gain faster access to critical information have a competitive advantage. • Organizations that can extend their information systems to include their customers and suppliers have a competitive advantage. • Organizations operate in more locations, national and international, then ever before.