Systems Analysis and Design 12

Learning Objectives Describe the six phases of the systems life cycle. Identify information needs and formulate possible solutions. Analyze existing information systems and evaluate the feasibility of alternative systems. Identify, acquire, and test new system software and hardware. Switch from an existing information system to a new one with minimal risk. Perform system audits and periodic evaluations. Describe prototyping and rapid applications development.

Introduction Most people in an organization are involved with an information system of some kind. For the organization to create and use the system requires thought and effort. In this chapter, you learn about a six step process for performing systems analysis and design.

System Analysis and Design Six-phase problem-solving procedure for examining and improving an information system System (key term) – a system is defined as a collection of activities and elements organized to accomplish a goal. To avoid confusion, the flow of information must follow a route that is defined by a set of rules and procedures. These at times need to be changed or revised. Systems analysis and design (key term) is a six-phase procedure for examining and improving an information system. These six stages make up the systems life cycle (Key term) . The Life Cycle is used by computer professionals known as systems analysts (key term) to study systems and determine what actions to take and how to use computer technology to assist. Preliminary Investigation (key term) – information, problems or needs are identified. Systems analysis (key term) – study the present system and specify new requirements Systems Design (key term)– The third phase is to design a new model or make adjustments to the current model to fit new needs or changes in technology Systems Development (key term)– The fourth phase is Development – This is the acquisition of new software and/or hardware and the testing of that new acquisition Systems Implementation (key term) – The information system is installed and people are trained. Systems Maintenance (key term) – is ongoing as the system is periodically evaluated and updated if necessary. The six-phase systems life cycle is used by computer professionals knows as systems analysts (key term) *The following slides provide an overview of each of the six phases

Phase 1: Preliminary Investigation The preliminary investigation determines the need for a new information system Preliminary investigation (key term) – determines the need for a new information system During Phase I, you have received a request from a user to see if there is a more efficient or easier way to get his/her job done There are three tasks to be completed: The problem is “defined” by you in coordination with the user Suggesting Alternative Systems. Prepare a short report to submit to higher management to see if management will finance the second phase – Systems Analysis

Phase 2: Systems Analysis Data is collected about the present system and then analyzed to determine the new requirements In Phase 2, the analyst observes and interviews people involved with the system that is being reviewed. Gathering Data - The organizational chart (key term) within the group helps determine who reports to whom and how information should be flowing through the system. Analyzing the data - The analyst might use a grid chart, or decision table, or a system flow chart. Check lists and automated tools are sometimes used in this phase. Documenting systems analysis - At the “end” of this phase, the analyst again writes a summary of his/her findings, called the systems analysis report (key term), to give to management before proceeding to step 3 – design a new system or restructuring the current system

Analyzing the Data in Phase 2 Top-down analysis method Grid charts System flowcharts Data flow diagrams Automated design tools Computer-aided software engineering tools (CASE) Documenting Systems Analyst Report Learn how information currently flows in your business and try to find out why it might not be flowing properly Top-down analysis method (key term)– used to identify the top-level components of a complex system; each component is broken down into smaller and smaller components making the component easier to analyze Some tools to use in analysis: Automated design tools (key term) Computer-aided software engineering (CASE) tools (key term) Used to design systems Relieve analysts of repetitive tasks Coordinate team activities Documenting – for higher management Systems Analysis Report – describes current information system, requirements for new system and possible development system Return

Data Analysis Tools – Grid Chart Grid charts (key term) show the relationship between input and output documents Grid Chart Return

Data Analysis Tools – System Flowchart System Flowchart Symbols System flowcharts (key term) show the flow of input data to processing and finally to output or distribution of information Return

Data Analysis Tools – Data Flow Diagram Data flow diagrams (key term) show the data or information flow within an information system The data is traced from its origin through processing, storage, and output Data Flow Diagram Symbols Return

Phase 3: Systems Design Three tasks Evaluate systems according to: Define the alternatives Select the best system Write a systems design report Evaluate systems according to: Economic feasibility Technical feasibility Operational feasibility This phase consists of looking at the feasibility of alternative systems: Economic feasibility (key term) - Will new system be economical? Technical feasibility (key term) - Is it technically possible? Operational feasibility (key term) - How will the new/revised system be received by employees, managers, clients? Selecting the best system - After the test system is selected, will it fit within the organization; is it flexible enough to be modified; can it be made secure; are the benefits worth the cost? Writing the systems design report (key term)– prepared for higher management; a report is prepared that presents costs versus benefits and outlines alternatives and makes a recommendation on which way to proceed.

Phase 4: Systems Development Three steps Acquire the software Acquire the hardware Test the new system Here it is important to emphasize that the software is acquired first – whether it is off-the-shelf or custom designed, software needs to be the first consideration. The product needs to accomplish the task that has been reviewed in the previous three steps. AFTER the software is determined, then the analyst(s) looks at the hardware – will the current hardware work or is there a need to upgrade? This can be as expensive as the software. Also important at this point is to consider if and where should new equipment go. Depending upon the activities of the user, he/she may or may not need new equipment when the system is implemented. Finally before moving on – TEST, TEST, TEST the proposed system! Be sure that it is accomplishing the task that was originally requested and recommended in the initial systems analysis. Use Sample Data. Check to verify that the person requesting the changes is actually one of the people (groups) testing the new system!

Phase 5: Systems Implementation Types of conversion Direct Parallel Pilot Phased Four Types of conversions (key term) or ways of systems implementation (key term) Direct approach (key term) – abandon the old system and start up a new one, not recommended, too risky. Advantage: free to pursue any approach, because you’re not constrained by an old system Parallel approach (key term) – old and new systems are operated side by side until new one is reliable Pilot approach (key term) – new system is tried out in only one part of the organization first Phased approach (key term) – new system is implemented gradually over a period of time Training should be considered very important but unfortunately most often overlooked.

Phase 6: Systems Maintenance Systems maintenance is an ongoing activity Two Parts Systems audit Periodic evaluation This step has been considered the “last” step in implementing systems analysis. It is important for ALL parties to realize that maintenance is on-going. All these people need to evaluate the system to be sure that all needs are being met and that technology is keeping up with the demand in the environment. Systems audit (key term) – the system’s performance is compared to the original design specifications to determine whether the new procedures are actually furthering productivity; further modifications may be needed and made Periodic evaluation – all systems should be evaluated from time to time to determine whether they are meeting the goals and providing the service as specified

Summary of Systems Life Cycle

Prototyping and Rapid Applications Development Alternatives to the systems life cycle Prototyping Rapid applications development (RAD) Prototyping software Prototyping (key term) is building a “model” of the system you want to implement and letting people try it out and give you feedback. While development time is shorter, managing the project itself and the cost can get interesting. RAD – Rapid Application Development (key term) – may cost more, the development time is short and the quality of the completed system is better because you use development software, specialized teams, and highly trained personnel.

Careers in IT A systems analyst plans and designs new systems, following the systems life cycle Requires a Bachelor’s degree in Computer Science or Information Systems and technical experience Can expect to earn an annual salary of $49,000 to $93,000

A Look to the Future ~ The Challenge of Keeping Pace To stay competitive with today’s fast business pace, new technologies must be incorporated Increased use of RAD and prototyping Increased use of outside consulting Because of the Internet and rapid advancements in technology, the 5-step analysis process is losing ground to more easily and quickly adaptable systems like prototyping and RAD Other companies are going to outside consulting firms to help upgrade and update their systems more rapidly What companies can you find that specialize in systems analysis and design?

Open-Ended Questions (Page 1 of 2) What is a system? What are the six phases of the systems life cycle? Why do corporations undergo this process? What are the tools used in the analysis phase? What is top-down analysis? How is it used? Have students turn to the end of Chapter 12 in their textbooks to view the same “Open-Ended” questions/statements

Open-Ended Questions (Page 2 of 2) Describe each type of system conversion. Which is the most commonly used? What is system maintenance? When does it occur? Explain prototyping and RAD. When might they be used by corporations? Have students turn to the end of Chapter 12 in their textbooks to view the same “Open-Ended” questions/statements