Modern Systems Analysis and Design Fifth Edition Chapter

Modern Systems Analysis and Design Fifth Edition Chapter 2 The Origins of Software 2. 1 cis 339

Learning Objectives ü Explain outsourcing ü Describe six different sources of software ü Discuss how to evaluate off-the-shelf software ü Explain reuse and its role in software development 22. cis 339

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. cis 339

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 n n A company that runs payroll applications for clients. A company that runs your applications at your site. Reason for outsourcing: n n n 24. 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 cis 339

Source of Software Information technology services firm. Packaged software producers. Enterprise-wide solutions Application service providers (ASPs) Open source software. In-house developers cis 339

Source of Software cis 339

Information Technology (IT) Services Firms Help companies develop custom information systems for internal use. Develop, host, and run applications for customers. Provide other services. cis 339

Systems Acquisition Packaged software producers n n 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. 28. cis 339

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. cis 339

Packaged Software Producers cis 339

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 211. cis 339

Application Service Providers (ASPs), is an organization that hosts and runs computer applications for other companies, typically on per-use or license basis. n Application service providers (ASPs) buy, install, maintain, and upgrade the applications. n Application service providers (ASPs) purchase or license applications from other software vendors. Examples Oracle ERP, Windows of Microsoft, and EDS. 212. cis 339

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. n MSPs provide the ability to gain access to large and complex systems without the expense and time-consuming implementation. cis 339

Open Source Software Freely available including source code. Developed by a community of interested people. Performs the same functions as commercial software. Examples: Linux, my. SQL, Firefox. cis 339

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. cis 339

Choosing OFF-The-Shelf Software (COTS) Most common Criteria used to choose COTS: n n n n 216. Cost Functionality Vendor support Viability of vendor Flexibility Documentation Response time Ease of installation cis 339

Choosing OFF-The-Shelf Software (COTS) Validating Purchased Software Information: n Use a variety of information sources: n Collect information from vendor. n Software documentation. n Technical marketing literature. n 217. 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. cis 339

REUSE, n Is the use of previously written software resources, especially objects and components, in new application. n 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 218. cis 339

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. 219. cis 339