Modern Systems Analysis and Design Fifth Edition

1. Modern Systems Analysisand DesignFifth Edition Chapter 2 The Origins of Software 2.1 cis339

2. Learning Objectives • Explain outsourcing • Describe six different sources of software • Discuss how to evaluate off-the-shelf software • Explain reuse and its role in software development 2.2 cis339

3. Introduction • There are various sources of software for organizations. • There are criteria to evaluate software from different sources. • The impact of reuse on software development. cis339

4. Systems Acquisition • Outsourcing is the practice of turning over responsibility of some to all of an organization’s information system application and operation to an outside firm. See table 2 for the top 10 global software companies • Outsourcing Examples • A company that runs payroll applications for clients. • A company that runs your applications at your site. • Reason for outsourcing: • Cost-effective. • Take advantage of economies of scale. • Free up internal resources • Reduce time to market. • Increase process efficiencies. • System development is a non-core activity for the organisation 2.4 cis339

5. Source of Software • Information technology services firm. • Packaged software producers. • Enterprise-wide solutions • Application service providers (ASPs) • Open source software. • In-house developers cis339

6. Source of Software cis339

7. Information Technology (IT) Services Firms • Help companies develop custom information systems for internal use. • Develop, host, and run applications for customers. • Provide other services. cis339

8. Systems Acquisition • Packaged software producers • Off-the-shelf software can be best meet 70% of an organization needs. • Some of these packaged cannot be modifies which call turnkey systems • Customer software producers, if no expertise in house and no suitable off-the-shelf system you will likely consult a company such EDS to help you develop you systems. 2.8 cis339

9. Packaged Software Producers • Serve many market segments. • Software ranges from broad-based packages (i.e. general ledger) to niche packages (i.e. day care management). • Software runs on microcomputers to large mainframes. • Prepackaged software is off-the-shelf software. • Prepackaged software is turnkey software (i.e. not customizable). • Off-the-shelf software at best meets 70 percent of organization’s needs. cis339

10. Packaged Software Producers cis339

11. Systems Acquisition • Enterprise Solution Software (ERP), is a system that integrates individual traditional business functions into series of modules so that a single transaction occurs seamlessly within a single information system rather than several separate systems. • Examples are SAP, JIT ..etc 2.11 cis339

12. Application Service Providers • Application Service Providers (ASPs), is an organization that hosts and runs computer applications for other companies, typically on per-use or license basis. • Application service providers (ASPs) buy, install, maintain, and upgrade the applications. • Application service providers (ASPs) purchase or license applications from other software vendors. • Examples Oracle ERP, Windows of Microsoft, and EDS. 2.12 cis339

13. Managed Service Provider (MSP) • An organization that remotely provides customized computer applications and network-based services for other companies for a monthly or per-use fee. • MSPs provide the ability to gain access to large and complex systems without the expense and time-consuming implementation. cis339

14. Open Source Software • Freely available including source code. • Developed by a community of interested people. • Performs the same functions as commercial software. • Examples: Linux, mySQL, Firefox. cis339

15. In House development • In-House development, it becoming less an less used by corporation to develop information systems in-House. • If you choose to acquire software from outside sources, this choice is made at the end of analysis phase. • If sufficient system development expertise with the chosen platform exists in-house, then some or all of the system can be developed by the organization’s own staff. • Hybrid solutions involving some purchased and some in-house components are common. cis339

16. Choosing OFF-The-Shelf Software (COTS) • Most common Criteria used to choose COTS: • Cost • Functionality • Vendor support • Viability of vendor • Flexibility • Documentation • Response time • Ease of installation 2.16 cis339

17. Choosing OFF-The-Shelf Software (COTS) • Validating Purchased Software Information: • Use a variety of information sources: • Collect information from vendor. • Software documentation. • Technical marketing literature. • Request for proposal (RFP) is a document provided to vendors that asks them to propose hardware and system software that will meet the requirements of a new system. 2.17 cis339

18. REUSE • REUSE, • Is the use of previously written software resources, especially objects and components, in new application. • Many vendors are working on developing libraries of components that can be retrieved and assembled as needed into desired application. • It can effective especially for object classes, which increase productivity, reduce defects, and reduce rework. For example for HP, a reuse programs result in cutting time over 70% from 18 months to 5 months. • However for reuse to work, the following issues should be addressed: - lack of methodology for creating, defining, and labeling reusable components. - lack of commitment to reuse. - lack of proper training - difficulty in measuring the economic gains from reuse 2.18 cis339

19. Summary • As a system analyst, you must be aware of where you can be obtain software that meets some or all of an organization’s needs. • You can obtain application from hardware vendors, packaged software vendors, and custom software developers, as well as from internal systems development resources. • You can hire an organization all of your systems development work. • You must know the criteria to use when choosing COTS system. 2.19 cis339