IT 21103/41103 System Analysis & Design

Chapter 07 System Design Phase

System Design “Good Design has no Substitute Bad Design no Escape”

System Design Users become very important during this phase….

System Design …You must define what the user actually needs in the new system.

System Design Key Concern for this Phase: “The USER comes first”

System Design Design Phase Termination: When the user is satisfied that the system will perform as intended or when monetary and/or time constraints are exceeded.

System Design System Types: Transaction-Processing System Real-Time Data Batch Processing

System Design Management Information System (MIS) Enterprise Data

System Design Decision Support System (DSS) Decision Support

System Design Local Area Networked Information System (LAN-IS) Local Communications

System Design Wide Area Networked Information System (WAN-IS) Wider Communication

System Design Expert Systems Information Network Analyze & Diagnose Problems

System Design Strategic Information System Outside Analysis

System Design Alternative Approaches: (See Figure 7-5, Page 179)

System Design Structured Design: Breaking the problem into more manageable parts

System Design Structured Design: 4GL – 4 th Generation Language Modular Design Object Programming

System Design Object-Oriented Design: Analysts skip the DFD & ERD Develop the OM instead (USD, Menu-Tree, System Flowchart)

System Design Object-Oriented Design: Makes system design easier when using 4GL programming languages

System Design Joint Application Design: Developed in the mid-1980’s Intense Formal Design Workshop Session

System Design Joint Application Design: Can also have several small informal sessions over the period of the analysis and design phases

System Design Design Specifications: Gives the User the first look at the system, and the Analyst a blueprint to build the system

System Design Design Specifications: Develop a New USD Enhances the previous USD to more closely match the users needs

System Design Design Prototyping: All Show – gives the user a practical look at the system during the design process

System Design Project Deliverable: The Preliminary Presentation A Formal Oral and Written Report

System Design Preliminary Presentation: Written Summary of Project Requirements Overview of General Design Concepts Proposed Timetable Proposed Project Budget

System Design Preliminary Presentation: Oral Introductions Visuals from Written Report Questions & Answer Period Preview of the Next Step

System Design The Presentation: Extremely Important to UsersAnalysts Project Supporters

System Design The Design Review Session Requires Careful Documentation

System Design Form Design: Create specific form designs to be used in the system

System Design Form Design: Today is mostly Graphical in nature Always on – ready for user input May be based on Internet design

System Design Form Design: Source Documents Must include some way for users to receive help about the new forms and a way to backup these forms for auditing purposes

System Design Graphical User Interface Dialogs (GUIDs) Instructs users how to use the form, and records their selections and inputs

System Design Graphical User Interface Dialogs (GUIDs) Should have a consistent look & feel

System Design Graphical User Interface Dialogs (GUIDs) Should provide Entrance to the database system

System Design Graphical User Interface Dialogs (GUIDs) Correct Errors ASAP, do not wait to look for errors when the system is completed

System Design Other Considerations: Design the system for the user not the analyst Make allowances for users who do not have adequate knowledge of computer technology

System Design Other Considerations: Make the Design as easy as possible, but still covers all the required system inputs/outputs

System Design Other Considerations: Forms need to be designed for the novice computer user Think about programs you have used that were difficult to understand

System Design Other Considerations: DOCUMENT EVERYTHING YOU DO DURING THIS PHASE Documentation is required during all phases, but this phase is most critical for keeping current documentation.

System Design Other Considerations: This phase is critical to the success of your project…make it count “Put yourself in the shoes of the user and stay there”

System Design Questions

Assignment # 07 Page Parts I & II Due: Nov 15 th