Introduction to System Analysis and Design (Definition of System & information system components) - Dr. Mahmoud Abu-Arra - Dr. Mahmoud Abu-Arra - Mr. Ahmad Al-Ghoul System Analysis and Design

Avicenna System Analysis and Design Introduction to SAD2 learning Objectives Describe the characteristics of system Describe the characteristics of system Define an information system and describe its components Define an information system and describe its components

Avicenna System Analysis and Design Introduction to SAD3 introduction Before talking about the characteristics of systems, and information system components let us have a historical view for the system analysis and design. Before talking about the characteristics of systems, and information system components let us have a historical view for the system analysis and design. The analysis and design of a computer based information systems began in the 1950s. The analysis and design of a computer based information systems began in the 1950s. Since then, the development environment has changed dramatically, driven by organizational needs as well as by rapid changes in the technological capabilities of computers Since then, the development environment has changed dramatically, driven by organizational needs as well as by rapid changes in the technological capabilities of computers In the 1950s, development focused on the processes the software performed In the 1950s, development focused on the processes the software performed Computer power was critical resource, efficiency of processing become the major goal Computer power was critical resource, efficiency of processing become the major goal Computer were large, expensive, and not very reliable Computer were large, expensive, and not very reliable All applications had to be developed in machine language or assembly language All applications had to be developed in machine language or assembly language Software had to be developed from scratch, because there was no software industry Software had to be developed from scratch, because there was no software industry

Avicenna System Analysis and Design Introduction to SAD4 introduction second step 1960s second step 1960s The second step begins with the first procedural, or third generation, computer programming languages in the beginning of 1960s The second step begins with the first procedural, or third generation, computer programming languages in the beginning of 1960s Computers were still expensive and large but it gets more smaller and faster, less expensive than 1950s Computers were still expensive and large but it gets more smaller and faster, less expensive than 1950s With the third generation programming languages, software industry begins, but most organizations still developed their applications from scratch using their in-house development staff With the third generation programming languages, software industry begins, but most organizations still developed their applications from scratch using their in-house development staff

Avicenna System Analysis and Design Introduction to SAD5 introduction Third step 1970s Third step 1970s Organizations began to realize how expensive it was to develop customized information systems for every application Organizations began to realize how expensive it was to develop customized information systems for every application early database management systems, using hierarchal and network models helped storage and retrieval of data early database management systems, using hierarchal and network models helped storage and retrieval of data The development of database management systems helped shift the focus of systems development from processes first to data first The development of database management systems helped shift the focus of systems development from processes first to data first

Avicenna System Analysis and Design Introduction to SAD6 introduction Fourth step 1980s Fourth step 1980s Microcomputers become key organizational tools Microcomputers become key organizational tools The software industry expanded greatly as more and more people began to write off-the-shelf software for microcomputers The software industry expanded greatly as more and more people began to write off-the-shelf software for microcomputers Developers began to write more and more applications in fourth generation languages, which unlike procedural languages, instructed a computer on what to do instead of how to do it Developers began to write more and more applications in fourth generation languages, which unlike procedural languages, instructed a computer on what to do instead of how to do it Computer-aided software engineering (CASE) tools were developed to make systems developers work easier Computer-aided software engineering (CASE) tools were developed to make systems developers work easier A computer get smaller, faster, and cheaper A computer get smaller, faster, and cheaper The operating systems for computers moved away from line prompt interface to windows and icon based interfaces The operating systems for computers moved away from line prompt interface to windows and icon based interfaces Organizations moved to applications with more graphics Organizations moved to applications with more graphics Organizations developed less software in-house and bought relatively more from software vendors Organizations developed less software in-house and bought relatively more from software vendors System developer’s job went through a transition from builder to integrator System developer’s job went through a transition from builder to integrator

Avicenna System Analysis and Design Introduction to SAD7 introduction Fifth step 1990s Fifth step 1990s Developers used visual programming environments, such as power builder or visual basic, to design the user interfaces for systems that run on client/server platforms Developers used visual programming environments, such as power builder or visual basic, to design the user interfaces for systems that run on client/server platforms Databases become relational or object oriented, and which may have been developed using software from firms such as Oracle, Microsoft. resided on the server Databases become relational or object oriented, and which may have been developed using software from firms such as Oracle, Microsoft. resided on the server Application logic resided on the same server with the database, alternatively, an organization may have decided to purchase its entire enterprise wide system Application logic resided on the same server with the database, alternatively, an organization may have decided to purchase its entire enterprise wide system More and more systems development efforts focused on the Internet, especially the web More and more systems development efforts focused on the Internet, especially the web

Avicenna System Analysis and Design Introduction to SAD8 introduction Sixth step the new century Sixth step the new century The focus on developing systems for the Internet and for firm’s intranets and extranets The focus on developing systems for the Internet and for firm’s intranets and extranets Many CASE tools, such as those developed by Oracle, now directly support Web application development Many CASE tools, such as those developed by Oracle, now directly support Web application development System implementation involves a three-tier design, with the database on one server, the application on a second server, and client logic located on user machines System implementation involves a three-tier design, with the database on one server, the application on a second server, and client logic located on user machines Moving to wireless system components, wireless devices, such as cell phones Moving to wireless system components, wireless devices, such as cell phones In some cases organizations not only do not develop the application in-house; they don’t even run the application in- house, choosing instead to use the application on a per-use basis by accessing in through an application service provider (ASP) In some cases organizations not only do not develop the application in-house; they don’t even run the application in- house, choosing instead to use the application on a per-use basis by accessing in through an application service provider (ASP)

Avicenna System Analysis and Design Introduction to SAD9 Characteristics of Systems A system A system interrelated components working together for a common purpose Information system (IS) Information system (IS) Arrangement of people, data, processes, information presentation and information technology that interact to support and improve day-to-day operations in a business as well as support the problem-solving and decision-making needs of management and users Arrangement of people, data, processes, information presentation and information technology that interact to support and improve day-to-day operations in a business as well as support the problem-solving and decision-making needs of management and users

Avicenna System Analysis and Design Introduction to SAD10 Characteristics of Systems Systems are made up of interrelated subsystems (e.g. a nuclear reactor is composed of boilers, reactor components etc.) Systems are made up of interrelated subsystems (e.g. a nuclear reactor is composed of boilers, reactor components etc.) Functional decomposition – dividing a system into components based on subsystems (which are in turn further divided into subsystems) Functional decomposition – dividing a system into components based on subsystems (which are in turn further divided into subsystems) Functional & Non-Functional components of a system Functional & Non-Functional components of a system System boundary – the separation between a system and its environment (where inputs and outputs cross) System boundary – the separation between a system and its environment (where inputs and outputs cross) Automation boundary – separation between the automated part of system and the manual part Automation boundary – separation between the automated part of system and the manual part

Avicenna System Analysis and Design Introduction to SAD11 Characteristics of Systems Manual Part of the System Automated Part of the System Automation boundary System boundary Environment Surrounding the System The system boundary and the automation boundary

Avicenna System Analysis and Design Introduction to SAD12 Characteristics of Systems output boundary interrelationship subsystem input General Depiction of a System

Avicenna System Analysis and Design Introduction to SAD13 Information System Components Information systems have five key components: hardware, software, data, processes, and people Information systems have five key components: hardware, software, data, processes, and people people processes data software hardware

Avicenna System Analysis and Design Introduction to SAD14 Information System Components Hardware Hardware Is the physical layer of the information system Is the physical layer of the information system Hardware includes: work stations, servers, networks, telecommunication equipments, cables, input and output devices and many others. Hardware has become more powerful that give information systems more opportunities, and it also cut costs by becoming less expensive.

Avicenna System Analysis and Design Introduction to SAD15 Information System Components Software Software Software refers to the programs which control the hardware and produce the desired information and results Software refers to the programs which control the hardware and produce the desired information and results Software consists of system software and application software Software consists of system software and application software System software manages the hardware components, which can include a single workstation or global network. Examples of system software include System software manages the hardware components, which can include a single workstation or global network. Examples of system software include operating systems operating systems security software, that protects the computer from intrusion security software, that protects the computer from intrusion utility programs, that handle specific tasks such as data backup and disk management. utility programs, that handle specific tasks such as data backup and disk management. Network operating system (NOS), which controls data, provide data security, manage network accounts. Network operating system (NOS), which controls data, provide data security, manage network accounts.

Avicenna System Analysis and Design Introduction to SAD16 Information System Components Software Software Application software, the programs that support day-to day business functions and provide process and manage the information user need. Application software can serve one or any number of users. Examples of company-wide applications, called Enterprise applications, include order processing system, payroll systems, and company communication network Application software, the programs that support day-to day business functions and provide process and manage the information user need. Application software can serve one or any number of users. Examples of company-wide applications, called Enterprise applications, include order processing system, payroll systems, and company communication network Application software includes horizontal and vertical systems Application software includes horizontal and vertical systems 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 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 systems is designed to meet the unique requirements of a specific business, such as a medical practice, or a video chain. A vertical systems is designed to meet the unique requirements of a specific business, such as a medical practice, or a video chain.

Avicenna System Analysis and Design Introduction to SAD17 Information System Components  Data  Is the raw material that an information system transforms into useful information  Data can be stored in various locations, called tables  The system can extract specific information by linking the tables Processes Processes Define the tasks and business functions that users, managers, and IT staff members perform to achieve specific results Define the tasks and business functions that users, managers, and IT staff members perform to achieve specific results Processes are the building blocks of an information system Processes are the building blocks of an information system Processes represent actual day-to-day business operations Processes represent actual day-to-day business operations

Avicenna System Analysis and Design Introduction to SAD18 Information System Components People People those who operate the system; those who provide its inputs and consume its outputs, and those who provide manual processing activities in a system, Users are the people who interact with an information system, both inside and outside the company those who operate the system; those who provide its inputs and consume its outputs, and those who provide manual processing activities in a system, Users are the people who interact with an information system, both inside and outside the company We can divide users to two types internal and external We can divide users to two types internal and external Internal users include administrators, managers, technicians, sales staff, and corporate officers Internal users include administrators, managers, technicians, sales staff, and corporate officers External users include customers who track their orders on the company’s Web site and suppliers who use a customer’s system to plan their manufacturing schedules. External users include customers who track their orders on the company’s Web site and suppliers who use a customer’s system to plan their manufacturing schedules.

Avicenna System Analysis and Design Introduction to SAD19 Sequence Summary In this sequence, you learned about how systems analysis and design in organizations has changed over the past 40 years In this sequence, you learned about how systems analysis and design in organizations has changed over the past 40 years A system interrelated components working together for a common purpose A system interrelated components working together for a common purpose Information system (IS) is arrangement of people, data, processes, information presentation and information technology that interact to support and improve day-to-day operations in a business Information system (IS) is arrangement of people, data, processes, information presentation and information technology that interact to support and improve day-to-day operations in a business Systems are made up of interrelated subsystems can be divided into sub systems depending on its functions Systems are made up of interrelated subsystems can be divided into sub systems depending on its functions The essential components of an information system are hardware, software, data, processes, and people The essential components of an information system are hardware, software, data, processes, and people

Avicenna System Analysis and Design Introduction to SAD20 Sequence Summary In this Sequence we have In this Sequence we have Described how systems analysis and design in organizations has changed over the past 40 years Described how systems analysis and design in organizations has changed over the past 40 years Defined the terms system and information system Defined the terms system and information system Described the characteristics of system Described the characteristics of system Described information system components Described information system components

Avicenna System Analysis and Design Introduction to SAD21 Reference [1] System Analysis and Design, Sixth Edition Authors: Gary B. Shelly, Thomas J. Cashman and Harry J. Rosenblatt, Authors: Gary B. Shelly, Thomas J. Cashman and Harry J. Rosenblatt, Publisher: SHELLY CASHMAN SEWIES. [2] Modern Systems Analysis and Design Third Edition Authors: Jeffrey A. Hoffer, Joey F. George, Joseph S. Valacich Authors: Jeffrey A. Hoffer, Joey F. George, Joseph S. Valacich Publisher: prentice hall Publisher: prentice hall