slike bài giảng ứng dụng xây dựng hệ thống thông tin chương 9 moving to design

9 Chapter 9: Moving to Design Systems Analysis and Design in a Changing World, 3 rd Edition 9 Systems Analysis and Design in a Changing World, 3rd Edition 2 Learning Objectives ◆ Discuss the issues related to managing and coordinating the design phase of the SDLC ◆ Explain the major components and levels of design ◆ Describe each design phase activity ◆ Describe common deployment environments and matching application architectures ◆ Develop a simple network diagram and estimate communication capacity requirements 9 Systems Analysis and Design in a Changing World, 3rd Edition 3 Overview ◆ This chapter: ● Completes the transition from analysis to design ● Discusses issues related to design of new system ● Describes all design phase activities ● Describes network and architecture design ◆ Analysis focuses on what system should do – business requirements ◆ Design is oriented toward how system will be built – defining structural components 9 Systems Analysis and Design in a Changing World, 3rd Edition 4 Understanding the Elements of Design ◆ Design is process of describing, organizing, and structuring system components at architectural design level and detailed design level ● Focused on construction ● Like developing blueprints ◆ Three questions: ● What components require systems design? ● What are inputs to and outputs of design process? ● How is systems design done? 9 Systems Analysis and Design in a Changing World, 3rd Edition 5 Components Requiring Systems Design 9 Systems Analysis and Design in a Changing World, 3rd Edition 6 Analysis Objectives to Design Objectives 9 Systems Analysis and Design in a Changing World, 3rd Edition 7 Moving from Analysis to Design ◆ Design: ● Converts functional models from analysis into models that represent the solution ● Focused on technical issues ● Requires less user involvement than analysis ◆ Design may use structured or OO approaches ● Database can be relational, OO or hybrid ● User interface issues 9 Systems Analysis and Design in a Changing World, 3rd Edition 8 Traditional Structured and Object-Oriented Models 9 Systems Analysis and Design in a Changing World, 3rd Edition 9 SDLC Phases with Design Phase Activities 9 Systems Analysis and Design in a Changing World, 3rd Edition 10 Design Phase Activities and Key Questions [...]... new and existing databases 15 9 Prototype for Design Details x Continue to create and evaluate prototypes during design phase x Prototypes confirm design choices: q q Network architecture q Controls q x Database Programming environment Rapid application development’s (RAD) design prototypes evolve into finished system 16 9 Design and Integrate the System Controls x Final design activity to ensure system... coordinating ongoing work The Project Team at RMO q x 9 As project team grows – structure may change Coordinating Information q CASE tools and central repository q Team communication and information coordination q Track open items and unresolved issues 18 System Development Information Stored in the CASE Repository 9 19 9 Deployment Environment x Deployment environment definition bridges analysis and design. . .9 Design and Integrate the Network x Network specialists establish network based on strategic plan x Project team typically integrates system into existing network x Technical requirements have to do with communication via networks x Technical issues handled by network specialists: q Reliability, security, throughput, synchronization 11 9 Design the Application Architecture... 24 9 A Possible Network Configuration for RMO 25 9 The Internet, Intranets, and Extranets x Internet – Global collection of networks that use TCP/IP networking protocols x Intranets q q x Private networks using same TCP/IP protocol as the Internet Limited to internal users Extranets q Intranet that has been extended outside the organization 26 9 Application Architecture x Consists of standards and tools... environment and expertise q Existing CASE tools and methodologies q Required interfaces to other systems q Operating system environment q Database management system environment 27 9 Client-Server Architecture x Client-Server divides programs into two types x Server – manages information system resources or provides well defined services for client x Client – communicates with server to request resources or... Service-Related Data Store 9 29 9 Client-Server Architectural Process x Decompose application into client and server programs, modules, or objects q Identify resources or services that can be centrally managed by independent software units x Determine which clients and servers will execute on which computer systems x Describe communication protocols and networks that connect clients and servers 30 9 Three-Layer... Delivery x Breaches of security x Fluctuating reliability of network throughput x Slow, throughput speeds to home users x 9 Volatile, changing standards 35 9 Network Design x Integrate network needs of new system with existing network infrastructure x Describe processing activity and network connectivity at each system location x Describe communications protocols and middleware that connects layers... controls) to protect organizational assets x Controls are needed for all other design activities q User interface – limit access to authorized users q System interface – protect from other systems q Application architecture – record transactions q Database – protect from software/hardware failure q Network design – protect communications 17 Project Management: Coordinating the Project x Coordinating Project... be distributed to multiple processors x Data layer – manages stored data in databases x Business logic layer – implements rules and procedures of business processing x View layer – accepts user input and formats and displays processing results 31 9 Three-Layer Architecture 32 9 Middleware x Aspect of distributed computing x Connects parts of an application and enables requests and data to pass between... pass between them x Teleprocessing monitors, transaction processing modules, object request brokers (ORBs) x Designers reply on standard frameworks and protocols incorporated into middleware 33 Internet and Web-based Application Architecture x Web is complex example of client-server architecture x Can use Web protocols and browsers as application interfaces x 9 Benefits q Accessibility q Low-cost communication . Objectives to Design Objectives 9 Systems Analysis and Design in a Changing World, 3rd Edition 7 Moving from Analysis to Design ◆ Design: ● Converts functional models from analysis into models. 9 Chapter 9: Moving to Design Systems Analysis and Design in a Changing World, 3 rd Edition 9 Systems Analysis and Design in a Changing World, 3rd Edition 2 Learning. (RAD) design prototypes evolve into finished system 9 Systems Analysis and Design in a Changing World, 3rd Edition 17 Design and Integrate the System Controls ◆ Final design activity to ensure