chap019 SYSTEM CONSTRUCTION AND IMPLEMENTATION

1、Whitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 119C H A P T E RSYSTEM CONSTRUCTION AND IMPLEMENTATIONWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 2C

2、hapter Sixteen Systems Construction & Implementation构造和实现阶段的目的。系统构造和实现阶段的工作内容。应用系统和系统测试。系统转换策略。Whitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 3Chapter Map 设计设计 功能系统功能系统 培训材料培训材料 运行系统运行系统 事后审计事后审计工作描述与问题描述(PIECES)系统改进目标(PIECES

3、) 企业战略规划企业战略规划 战略信息系统计划战略信息系统计划参与者参与者系统系统所有者所有者 系统用户系统用户 系统设计员系统设计员系统构造人员系统构造人员 系统分析员和项目经理系统分析员和项目经理信息范围信息范围与构想与构想范围定义项目管理和过程管理 可行性分析与风险管理战略企业技术框架战略企业技术框架目标目标改进业务知识改进业务知识目标目标改进业务过程改进业务过程目标目标改进业务沟通改进业务沟通功能范围功能范围与构想与构想沟通范围沟通范围与构想与构想数据库数据库物理设计物理设计业务过程设计业务过程设计软件规格说明书软件规格说明书接口物理设计接口物理设计数据库方案数据库方案商用软件包商用软

4、件包定制应用软件定制应用软件用户界面方案用户界面方案接口方案接口方案限制：批准的网络技术限制：批准的网络技术限制限制批准的数据库技术批准的数据库技术限制限制批准的过程技术批准的过程技术限制限制批准的接口技术批准的接口技术系统系统所有者所有者 业务需求描述用例图用例图系统方案建议系统方案建议应用架构应用架构中间件中间件中间件中间件问题分析需求分析逻辑设计决策分析物理设计构造与测试安装与发布Whitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei Universi

5、ty of Technology 4What Is System Construction and Implementation?Systems construction the development, installation, and testing of system components. A common but unfortunate synonym is systems development (more frequently used to describe the entire life cycle.)Systems implementation the installat

6、ion and delivery of the entire system into production. Day-to-day operationWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 5The Context of System Construction and ImplementationWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIG

7、N METHODS6th EditionSchool of Management, HeBei University of Technology 6Tasks for Completing The Construction PhaseWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 7Construction Phase 1. Build and Test NetworksOften system bu

8、ild around existing networks.If system calls for new network functionality, must by built and tested prior to programs that use that it.Roles Network designer Designs LAN and WAN connectivity Network administrator builds and tests Network architecture standards Security Systems analyst Facilitates E

9、nsures that business requirements are not compromisedWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 8Construction Phase 2. Build and Test Databases Implement database schema Test with sample data Deliver unpopulated database

10、structure Roles System users Provide and/or approve test data Database designer/programmer Build tables, views, stored procedures (if relational database) Database administrator “Tune” database for optimum performance Security Backup and recovery Systems Analyst Build non-corporate, applications-ori

11、ented database Ensures business requirements complianceWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 9Construction Phase 3. Install and Test New SoftwareIf system requires purchased or leased software, must be installed and

12、tested.Roles Systems analyst Clarifies business requirements System designer Clarifies integration requirements Network administrator Install software package Software vendor/consultant Assist in installation and testing Applications programmer Test according to integration requirementsWhitten Bentl

13、ey DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 10Construction Phase 4. Write and Test New ProgramsDevelop in-house programs Reuse available software components in library Write new components Test DocumentRoles Systems analyst Clarifies b

14、usiness requirements System designer Clarifies program design and integration requirements Application programmer (or team) Writes and tests in-house softwareWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 11Levels of TestingS

15、tub test - a test performed on a subset of a program. Individual events or modules of a program. Testing of an isolated subset of a program.Unit or program test a test performed on an entire program. All the events and modules tested as an integrated unit. Systems test a test performed on an entire

16、system Ensures that application programs written and tested in isolation work properly when integrated into the total system.Whitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 12Tasks for Completing The Implementation PhaseWhitte

17、n Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 13Implementation Phase - 1. Conduct System TestTest network, databases, purchased software, new in-house software, and existing software to make sure it all works together.Roles System

18、s analyst Develops system test data Communicates problems and issues System builders (database, network, programmers) Resolve problems revealed during testing System owners and users Verify whether or not system operates correctlyMay result in return to construction phase Iterate until successful sy

19、stem testWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 14Implementation Phase 2. Prepare Conversion PlanPlan for how to convert from old system to new system. How to install and populate databases How to train users Finalize

20、 documentation Conversion issuesRoles System analyst/Project manager Develop a detailed conversion plan Steering committee Approves plan and timetableWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 15Installation StrategiesAbr

21、upt cutoverParallel conversionLocation conversionStaged conversionLocationsVersionsWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 16Systems Acceptance TestSystems acceptance test a test performed on the final system wherein u

22、sers conduct a verification, validation, and audit test. Uses real data over an extended time period Extensive test that addresses: verification testing, validation testing, and audit testing. Verification testing runs the system in a simulated environment using simulated data. Alpha testing Simulat

23、ed environment using simulated data Checks for errors and omissions regarding end-use and design specificationsWhitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 17Systems Acceptance Test (continued)Validation testing runs the sy

24、stem in a live environment using real data. Beta testing Live environment using real data Testing: Systems performance (throughput and response time) Peak workload performance Human engineering Methods and procedures Backup and recoveryAudit testing certifies that the system is free of errors and is

25、 ready to be placed into operation. Whitten Bentley DittmanSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 18Implementation Phase 3. Install DatabasesPopulate new system databases with existing data from old system Generally have to restructure data

26、 as it is populated Must confirm that data is translated correctlyRoles Application programmers Write (or use) special programs to extract data from existing databases and populate new databases Systems analyst/designer Calculate database sizes and estimate time for installationWhitten Bentley Dittm

27、anSYSTEMS ANALYSIS AND DESIGN METHODS6th EditionSchool of Management, HeBei University of Technology 19Implementation Phase 4. Train UsersSystem users trained and provided with documentationRoles System analyst Plan trainings Conduct trainings Write documentation Help users through the learning period System owners Approve release time for training System users Attend training Accept systemWhitten Bentley DittmanSYSTEMS ANALYSIS AND DES