C HAPTER 19 AIS Development Strategies © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 172 INTRODUCTION • Questions to be addressed in this chapter include: – How organizations buy software, hardware, and vendor services? – How information systems departments develop custom software? – How end users develop, use and control computer-based information systems? – Why organizations outsource their information systems, and what are the benefits and risks of doing so? – How are prototypes used to develop an AIS, and what are the advantages and disadvantages? – What is computer-aided software engineering, and how is it used in systems development? © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 172 INTRODUCTION • Companies can experience a number of difficulties in developing an AIS, including: – Projects are backlogged for years because of the high demand for resources – The newly designed system doesn’t meet user needs – The process takes so long that by the time it’s complete, it’s obsolete – Users can’t adequately specify their needs – Changes to the AIS are often difficult to make after requirements have been written into the specifications © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 172 INTRODUCTION • We’ll be discussing how to obtain a new information system by: – Purchasing prewritten software; – Developing software in-house; or – Outsourcing • We’ll also discuss how to hasten or improve the development process through: – Business process reengineering – Prototyping – Computer-aided software engineering (CASE) tools © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 172 INTRODUCTION • We’ll be discussing how to obtain a new information system by: – Purchasing prewritten software – Developing software in-house; or – Outsourcing • We’ll also discuss how to hasten or improve the development process through: – Business process reengineering – Prototyping – Computer-aided software engineering (CASE) tools © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 172 PURCHASING PREWRITTEN SOFTWARE • In the early days of computers, companies were rarely able to buy software to meet their needs • But commercially available packages are now outpacing custom-developed software as old systems are replaced © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 172 PURCHASING PREWRITTEN SOFTWARE • Canned software is sold on the open market to a broad range of users with similar requirements – Some companies sell hardware and software together as a package • These systems are called turnkey systems • Many are written by vendors who specialize in a particular industry © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 172 PURCHASING PREWRITTEN SOFTWARE – A major problem with canned software: • It often does not meet all of a company’s information needs • Can be overcome by modifying the canned software – Usually best done by the vendor – Unauthorized modifications may render the program unreliable and unstable © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 172 PURCHASING PREWRITTEN SOFTWARE • Companies can also acquire software through application service providers (ASPs) – ASPs host Web-based software and deliver it to clients over the Internet – Companies don’t have to buy, install, or maintain canned software; they simply “rent” it – If you used an online version of a package like TurboTax to prepare your taxes, that’s a consumer version of renting software over the Internet © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart of 172 PURCHASING PREWRITTEN SOFTWARE – Advantages of ASPs: • Reduction of software costs and administrative overhead • Automated software upgrades • Scalability as the business grows • Global access to information • Access to skilled IT personnel • Ability to focus on core financial competencies rather than IT © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 10 of 172 PROTOTYPING • Disadvantages of prototyping: – Significant user time – Less efficient use of system resources – Incomplete system development – Inadequately tested and documented systems – Negative behavioral reactions • If the prototype is discarded, users may be upset about using it and losing it • May also be dissatisfied if all their suggestions are not incorporated or if they have to go through too many iterations © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 158 of 172 PROTOTYPING • Disadvantages of prototyping: – Significant user time – Less efficient use of system resources – Incomplete system development – Inadequately tested and documented systems – Negative behavioral reactions – Never-ending development • If not managed properly, the development could get stuck in a terminal loop © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 159 of 172 INTRODUCTION • We’ll be discussing how to obtain a new information system by: – Purchasing prewritten software – Developing software in-house – Outsourcing • We’ll also discuss how to hasten or improve the development process through: – Business process reengineering – Prototyping – Computer-aided software engineering (CASE) tools © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 160 of 172 Computer-Aided Software Engineering (CASE) Tools • Traditionally, software developers have created software to simplify the work of others, but not for themselves • Computer-aided software (or systems) engineering (CASE) tools are an integrated package of computer-based tools that automate important aspects of the software development process – Used to plan, analyze, design, program, and maintain an information system – Also used to enhance efforts of managers, users, and programmers in understanding information needs © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 161 of 172 Computer-Aided Software Engineering (CASE) Tools • CASE tools not replace skilled designers, but provide developers with effective support for all SDLC phases • CASE software typically includes tools for: – Strategic planning – Project and system management – Database design – Screen and report layout – Automatic code generation © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 162 of 172 Computer-Aided Software Engineering (CASE) Tools • Advantages of CASE technology: – Increased productivity • Can generate bug-free code from system specifications • Can automate repetitive tasks © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 163 of 172 Computer-Aided Software Engineering (CASE) Tools • Advantages of CASE technology: – Increased productivity – Improved program quality • Can simplify enforcement of structured development standards, which: – Improves quality of development – Reduces threat of serious design errors • Can check internal accuracy of design and detect inconsistencies © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 164 of 172 Computer-Aided Software Engineering (CASE) Tools • Advantages of CASE technology: – Increased productivity – Improved program quality – Cost savings • Cost savings of up to 80–90% are possible © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 165 of 172 Computer-Aided Software Engineering (CASE) Tools • Advantages of CASE technology: – Increased productivity – Improved program quality – Cost savings – Improved control procedures • Encourages development early in the design process of: – – – – System controls Security measures System auditability Error handling procedures © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 166 of 172 Computer-Aided Software Engineering (CASE) Tools • Advantages of CASE technology: – Increased productivity – Improved program quality – Cost savings – Improved control procedures – Simplified documentation Automatically documents as the system development progresses © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 167 of 172 Computer-Aided Software Engineering (CASE) Tools • Problems with CASE technology: – Incompatibility • Some tools don’t interact effectively with some systems © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 168 of 172 Computer-Aided Software Engineering (CASE) Tools • Problems with CASE technology: – Incompatibility – Cost • Some packages > $360,000 © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 169 of 172 Computer-Aided Software Engineering (CASE) Tools • Problems with CASE technology: – Incompatibility – Cost – Unmet expectations • Only 37% of CIOs believe they achieved expected benefits © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 170 of 172 SUMMARY AND CONCLUSIONS • You’ve learned: – How organizations buy software, hardware, and vendor services – How information systems departments develop custom software – How end users develop, use, and control computer-based information systems – Why organizations outsource their information systems, as well as the benefits and risks of doing so © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 171 of 172 SUMMARY AND CONCLUSIONS • You’ve also learned: – What reengineering processes entail and when they are appropriate – How prototypes are used to develop an AIS and when it is advantageous to so – What computer-aided software engineering is and how it’s used in systems development © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/Steinbart 172 of 172 ... systems are called turnkey systems • Many are written by vendors who specialize in a particular industry © 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/ Steinbart. .. 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/ Steinbart of 172 INTRODUCTION • We’ll be discussing how to obtain a new information system by: – Purchasing prewritten... 2008 Prentice Hall Business Publishing Accounting Information Systems, 11/e Romney/ Steinbart of 172 INTRODUCTION • We’ll be discussing how to obtain a new information system by: – Purchasing prewritten