1. Copyright 2002 Prentice-Hall, Inc. Modern Systems Analysis and Design Third Edition Jeffrey A. Hoffer Joey F. George Joseph S. Valacich Chapter 11 Selecting the Best Alternative Design Strategy 11.1

2. Learning Objectives Describe different sources of software Learn to assemble the various pieces of an alternative design strategy Learn how to generate at least three alternative design strategies Discuss selecting the best design strategy using both qualitative and quantitative methods 11.2

3. Learning Objectives Learn how to use the results of the analysis phase to update a Baseline Project Plan (BPP) Discuss design strategies and how they are applied to the Internet 11.3

4. Selecting the Best Alternative Design Strategy Two basic steps 1.Generate a comprehensive set of alternative design strategies 2.Select the one design strategy that is most likely to result in the desired information system 11.4

5. Selecting the Best Alternative Design Strategy Deliverables 1. At least three substantially different system design strategies for building the replacement information system 2. A design strategy judged most likely to lead to the most desirable information system 3. A Baseline Project Plan (BPP) for turning the most likely design strategy into a working information system 11.5

6. Generating Alternative Design Strategies Best to generate three alternatives Low-end  Provides all required functionality users demand with a system that is minimally different from the current system High-end  Solves problem in question and provides many extra features users desire Midrange  Compromise of features of high-end alternative with frugality of low-end alternative 11.6

7. Drawing Bounds on Alternative Designs First: Minimum Requirements: Mandatory features versus desired features Mandatory features: are those that every one agrees are necessary to solve the problem or meet opportunity. desired features: are those that users could live without. 11.7

8. Drawing Bounds on Alternative Designs Forms of features  Data  Outputs  Analyses  User expectations on accessibility, response time and turnaround time

9. Drawing Bounds on Alternative Designs Second: Constraints on System Development Date when the replacement system is needed Financial and human resources Elements of the current system that cannot change Legal and contractual considerations Dynamics of the problem 11.9

10. Issues to Consider in Generating Alternatives Outsourcing The practice of turning over responsibility of some to all of an organization’s information systems applications and operations to an outside firm Can provide a cost effective solution 11.1010

11. Issues to Consider in Generating Alternatives Sources of Software Hardware manufacturers Packaged software producers Custom software producers Enterprise solution software Application Service Providers In-house development 11.11

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13. Criteria for Choosing Off-the-Shelf Software Cost In-House versus purchased Functionality Mandatory, essential and desired features Vendor Support Installation Training Technical Support Viability of Vendor 11.13

14. Criteria for Choosing Off-the-Shelf Software Flexibility Ease of customization Documentation User documentation Technical documentation Response Time Ease of Installation 11.14

15. Hardware and Software Issues Existing Platform 1.Lower costs 2.Information system staff is familiar with operation and maintenance 3.Increased odds of successfully integrating system with existing applications 4.No added costs of converting old systems to new platform or transferring data New Hardware and System Software 1.Some software components will only run on new platform 2.Developing system for new platform gives organization opportunity to upgrade technology holdings 3.New requirements may allow organization to radically change its computing operations 11.15

16. Implementation and Organizational Issues Implementation Issues Technical and social aspects of implementation need to be addressed Training Disruption of work Organizational Issues Overall cost and availability of funding Management support User acceptance 11.16

17. Updating the Baseline Project Plan (BPP) The Baseline Project Plan (BPP) was developed during project initiation and planning Baseline Project Plan (BPP) can be used as an outline of a status report at analysis phase Schedule will be updated to reflect actual activities and durations An oral presentation of project status is typically made at this phase 11.17

18. Summary Sources of Software Identifying requirements and constraints Generating alternative design strategies Selecting the best design strategy Updating a Baseline Project Plan (BPP) Selecting the best design strategy for Internet applications 11.18