System Analysis and Design - Mr. Ahmad Al-Ghoul Hi students how are you doing today This is the fifth sequence from the analysis chapter And today we will have an overview of the analysis phase

System Analysis and Design System Analysis Learning Objectives Describe systems analysis phase activities and the end product of the systems analysis phase Describe the Unified Modeling Language (UML) Describe Functional Decomposition Diagram ( FDD ) Explain why analysts using models Describe CASE tools, objectives, and types Avicenna System Analysis and Design System Analysis

System Analysis and Design System Analysis Learning Objectives List and describe system requirements, including outputs, inputs, processes, performance, and controls Explain the importance of scalability Define total cost of ownership (TCO) and explain the concept Avicenna System Analysis and Design System Analysis

System Analysis and Design System Analysis Introduction The overall objective of the systems analysis phase is to understand the proposed system, ensure that it will support business requirement, and build solid foundation of system development. Systems Analysis Activities The systems analysis phase includes three main activates Requirements modeling Data and process modeling Development Strategies Avicenna System Analysis and Design System Analysis

Systems Analysis Phase Overview requirements Modeling Requirements modeling involves Fact finding Describing the current system and identification of the requirements for the new system which includes Outputs: electronic or printed information produced by the system Inputs: data that enters the system Processes: the logical rules that are applied to transform the data into information Performance: the system characteristics, speed, volume, capacity, availability, and reliability Security: hardware, software, and procedural controls that protect the system and data from internal or external threats Avicenna System Analysis and Design System Analysis

Systems Analysis Phase Overview Data and process modeling Represent graphically system data and process using various techniques. Development Strategies Evaluation of alternative solutions Preparation of the system requirements document System requirements document is an overall design for the new system Avicenna System Analysis and Design System Analysis

Systems Analysis Phase Overview Modeling tools and techniques Modeling involves graphical methods and non-technical language that represent the system at various stages of development There are various tools to describe business processes, requirements, and user interaction with the system Avicenna System Analysis and Design System Analysis

Modeling Tools and Techniques Analysts using models to: Concentrate on important features of the system, pay less attention to less important ones; Able to respond to changes or changes in user’s requirements with low cost and risk; Properly understand users’ environment and write documents in the same way that designers and programmers construct the system. Avicenna System Analysis and Design System Analysis

Modeling Tools and Techniques CASE Tools ( computer-aided software engineering ) CASE tools have been developed for internal use and for sale by several firms, including Oracle ( Designer), IBM ( Rational Rose ) Automated software tool used by systems analysts to develop information systems Used to support or automate activities throughout the systems development life cycle (SDLC) CASE tools include diagramming tools for data flow diagrams and other graphical aids, screen and report design tools, and other special-purpose tools Avicenna System Analysis and Design System Analysis

Modeling Tools and Techniques Objectives of CASE Improve quality of systems developed Increase speed of development and design Ease and improve testing process through automated checking Improve integration of development activities via common methodologies Improve quality and completeness of documentation Help standardize the development process Improve project management Simply program maintenance Promote reusability Improve software portability Avicenna System Analysis and Design System Analysis

Modeling Tools and Techniques Functional Decomposition Diagram ( FDD ) A top-down representation of a function or process A function diagram only shows what to do not how to do. FDD is a process of division, from a higher function to appropriate smaller functions. FDD need to be presented clearly, simply, exactly, and fully . FDD can be used at several stages of systems development Avicenna System Analysis and Design System Analysis

Modeling Tools and Techniques Four-level functional decomposition diagram (FDD) of a library system. Avicenna System Analysis and Design System Analysis

Modeling Tools and Techniques Unified Modeling Language ( UML ) UML is a method of visualizing and documenting software systems design UML uses object-oriented design concepts UML is independent of any specific programming language UML used to describe business processes and requirements generally UML provides various graphical tools Avicenna System Analysis and Design System Analysis

System Requirements Checklist System developers must identify and describe all system requirements System Requirements are a characteristics or features that must be included in an information system to satisfy business requirements and be acceptable to users Avicenna System Analysis and Design System Analysis

System Requirements Checklist Five categories of system requirements Outputs Inputs Processes Performance Controls In the next slides some examples of system requirements Avicenna System Analysis and Design System Analysis

System Requirements Checklist Outputs The Web site must report online volume statistics every four hours, and hourly during peak periods Inputs The department head must enter overtime hours on a separate screen Avicenna System Analysis and Design System Analysis

System Requirements Checklist Processes The student records system must calculate the GPA at the end of each semester Performance Response time must not exceed four seconds Controls An employee record must be added, changed, or deleted only by a member of the human resources department Avicenna System Analysis and Design System Analysis

Future Growth, Costs, and Benefits In addition to the system requirements, system analyst must consider Scalability Total Cost of Ownership Avicenna System Analysis and Design System Analysis

Future Growth, Costs, and Benefits Scalability System’s ability to handle increased business volume and transactions in the future A scalable system offers a better return on the initial investment To evaluate, you need information about projected future volume for all outputs, inputs, and processes Avicenna System Analysis and Design System Analysis

Future Growth, Costs, and Benefits Total cost of ownership (TCO) A number that is used in assessing costs, which includes ongoing support and maintenance costs, as well as acquisition costs. TCO especially important if the development team is evaluating several alternatives One problem is that cost estimates tend to understate indirect costs Systems analysts should try to identify indirect costs and include them in TCO estimates The end Avicenna System Analysis and Design System Analysis

System Analysis and Design System Analysis Sequence Summary The systems analysis phase includes three activities: requirements modeling, data and process modeling, and consideration of development strategies The main objective is to understand the proposed project and build a solid foundation for the systems design phase You identify the business-related requirements for the new information system, including outputs, inputs, processes, performance, and controls You consider scalability to ensure that the system can support future growth and expansion You also estimate total cost of ownership (TCO) to identify all costs, including indirect costs UML is a method of visualizing and documenting software systems design CASE tools are automated software tool used by systems analysts to develop information systems Avicenna System Analysis and Design System Analysis

System Analysis and Design System Analysis Sequence Summary In this Sequence we have Described the systems analysis phase including three activities: requirements modeling, data and process modeling, and consideration of development strategies Explained the main analysis objective that is to understand the proposed project and build a solid foundation for the systems design phase identified the business-related requirements for the new information system, including outputs, inputs, processes, performance, and controls Identified the fact-finding process includes interviewing, document review, observation, questionnaires, sampling, and research Described the Unified Modeling Language (UML) Described Functional Decomposition Diagram ( FDD ) Explained why analysts using models Describe CASE tools, objectives, and types Avicenna System Analysis and Design System Analysis

System Analysis and Design System Analysis Reference [1] System Analysis and Design, Sixth Edition 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 Publisher: prentice hall Avicenna System Analysis and Design System Analysis