1. 1 BTEC HNC Systems Support Castle College 2007/8 Systems Analysis Lecture 8 Moving from Analysis to Design Design Strategies

2. 2 BTEC HNC Systems Support Castle College 2007/8 Lecture Objectives Explore final stages of the Systems Analysis Phase of the SDLC Look at acquisition strategies Explain Outsourcing Contents of Requirements Document Presentation to Management Final decision & transition to design

3. 3 BTEC HNC Systems Support Castle College 2007/8 References Systems Analysis & Design Shelley Cashman and Rosenblat 6 th Ed. Thomson (2006) Eva and Skidmore (2004). Introducing Systems Development. Palgrave Macmillan Satzinger JW, Jackson RB and Burd SD (2004). Systems Analysis and Design in a Changing World. 3 rd edition. Thomson

4. 4 BTEC HNC Systems Support Castle College 2007/8 Systems Analysis Stages Requirements modelling Data and process modelling Evaluation of alternative solutions Preparation of the system requirements Document to management First stages Later and final stages

5. 5 BTEC HNC Systems Support Castle College 2007/8 Completion of Analysis Phase 1.Performance 2.Accuracy 3.Completeness “To complete the systems analysis phase, you must prepare the system requirements document and your presentation to management” – Shelley Cashman p221 The Systems Requirements Document is important because it is the starting point for measuring the: Of the proposed system before design begins

6. 6 BTEC HNC Systems Support Castle College 2007/8 System Requirements Document Specification The system requirements document is like a contract that identifies what the system developers must deliver to the users One essential aspect of information is the estimate of volume and future growth of an organisation’s information system Other considerations include Architecture, Security, Backup & Recovery (only if necessary, as these are usually specified within the Design documentation

7. 7 BTEC HNC Systems Support Castle College 2007/8 System Requirements Document Sometimes called the ‘Software Requirements Specification’ Contains the requirements for the new system Describes alternatives that were considered Makes specific recommendations to management

8. 8 BTEC HNC Systems Support Castle College 2007/8 Writing System Requirements Documents (SRD) The system requirements document can be lengthy – so it needs to be: –Organised and clear –Easy to read and use by all interested parties Contents of the SRD will differ with the company but should include a number of essential items

9. 9 BTEC HNC Systems Support Castle College 2007/8 Contents of the SRD An analysis of the unique business requirements (look at current systems / business processes, but not extensive documentation) An analysis of cost and benefits of the various options A specification of hardware, software and personnel constraints

10. 10 BTEC HNC Systems Support Castle College 2007/8 Contents of the SRD A request for proposals or quotations (to put out to tender or enable decisions on the following phases) An evaluation of the alternative bids Recommendations

11. 11 BTEC HNC Systems Support Castle College 2007/8 Selecting Development Path 1.Impact of the Internet 2.Software outsourcing options 3.In house software development options Important decision which needs to consider 3 key topics

12. 12 BTEC HNC Systems Support Castle College 2007/8 Impact of the Internet “Many software industry leaders (including Microsoft) believe that the concept of software as a service represents a new way of looking at software acquisition and use.” - Shelley Cashman P198 www.siia.net/software/groups_sasi.asp IBM's WebSphere and Microsoft's.NET are Web-based software development environments

13. 13 BTEC HNC Systems Support Castle College 2007/8 Traditional Software Selection Traditionally software vendors would develop and sell application packages to customers Customers would buy the licence and some maintenance agreement

14. 14 BTEC HNC Systems Support Castle College 2007/8 Software Selection Today: Traditional software vendors are still around So are many forms of outsourcing services Now ‘Application service providers’ include ones offering Internet services

15. 15 BTEC HNC Systems Support Castle College 2007/8 Activity Time Group A: Make a list of the advantages and disadvantages of traditional system development for an organisation Group B: Make a list of the advantages and disadvantages of outsourcing

16. 16 BTEC HNC Systems Support Castle College 2007/8 Software Outsourcing Options Outsourcing (definition): Outsourcing is the transfer of information system development, operation or maintenance to an outside firm that provides these services for a fee. This can be on a temporary, or a long term basis.

17. 17 BTEC HNC Systems Support Castle College 2007/8 e.g. www.oracle.com/outsourcing ‘On Demand’ Service - provides E-business applications on a fixed fee basis

18. 18 BTEC HNC Systems Support Castle College 2007/8 Offshore Outsourcing Offshore, or global outsourcing refers to the practice of shifting IT development, support and operations to other countries Many firms are sending work abroad at an increasing rate

19. 19 BTEC HNC Systems Support Castle College 2007/8 In-house Software Development A company can choose to develop its own systems or purchase and customise, and implement a software package The most important factor is – Total Cost of Ownership ( T.C.O.) (Maintenance is the biggest cost) Companies can also develop user applications from software packages

20. 20 BTEC HNC Systems Support Castle College 2007/8 Shelley Cashman et al In-house Software Development

21. 21 BTEC HNC Systems Support Castle College 2007/8 Make or Buy Decision Definitions: 1.The company’s IT Department makes and develops in-house software 2.A software package is obtained from a vendor or application service provider The choice between developing or purchasing is called a make or buy or make or build decision

22. 22 BTEC HNC Systems Support Castle College 2007/8 Comparison of factors as an aid to decision making

23. 23 BTEC HNC Systems Support Castle College 2007/8 Presentation to Management Takes place at the end of Systems Analysis phase One of the most critical milestones in the Systems development process Managers make key decisions that affect the future development of the system

24. 24 BTEC HNC Systems Support Castle College 2007/8 Presentations Should Begin with a brief overview of the purpose and objectives of the system project Summarise the primary viable alternatives Explain why the evaluation and selection team chose the recommended alternatives

25. 25 BTEC HNC Systems Support Castle College 2007/8 Presentations Should Allow time for discussion and questions Obtain a final decision from the management or agree a timetable for the next step in the process

26. 26 BTEC HNC Systems Support Castle College 2007/8 There are 5 alternatives 1.Implement an outsourcing alternative 2.Develop an in-house system 3.Purchase or customise a software package 4.Perform additional systems analysis to further explore the options 5.Stop all further work – close project.

27. 27 BTEC HNC Systems Support Castle College 2007/8 In Conclusion Final stages of the Systems Analysis Phase of the SDLC Acquisition strategies Outsourcing Contents of SRD Presentation to Management Final decision on next phase