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Fundamentals of requirements Options for designing and conducting requirements analysis interviews Advantages and disadvantages of various requirements analysis methods Joint Application Design (JAD) Value of Prototyping during analysis Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.2

 Gather information on what the system should do from many sources › Users › Reports › Forms › Procedures Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.3

 Characteristics for Gathering Requirements › Impertinence  Question everything › Impartiality  Find the best organizational solution › Relaxation of constraints  Assume anything is possible and eliminate the infeasible › Attention to detail  Every fact must fit with every other fact › Reframing  View the organization in new ways Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.4

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 Interviewing and Listening Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.7

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 Interviewing and Listening › Gather facts, opinions, and speculations › Observe body language and emotions › Interview Questions  Open-Ended  No pre-specified answers  Used to probe for unanticipated answers  Close-Ended  Respondent is asked to choose from a set of specified responses  Work well when the popular answers to questions are known  Do not require a long period of time, and can cover a greater number of topics Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.10

 Directly Observing Users › Serves as a good method to supplement interviews › Often difficult to obtain unbiased data  People often work differently when being observed Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.11

 Types of Information to be discovered: › Problems with existing system › Opportunity to meet new need › Organizational direction › Title and names of key individuals › Values of organization › Special information processing circumstances › Rules for processing data Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.12

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 Joint Application Design (JAD) › Brings together key users, managers, and systems analysts › Purpose: collect system requirements simultaneously from key people › Conducted off-site Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.14

 Participants › Session leader › Users › Managers › Sponsor › Systems analysts › Scribe › IS staff  End Result - Documentation detailing › Existing system › Features of a replacement system Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.15

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 Search for and implementation of radical change in business processes to achieve breakthrough improvements in products and services  Goals › Reorganize complete flow of data in major sections of an organization › Eliminate unnecessary steps › Combine steps › Become more responsive to future change Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.17

 Identify specific activities that can be improved through BPR  Disruptive Technologies › Technologies that enable the breaking of long-held business rules that inhibit organizations from making radical business changes › See Table 5-5 Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.18

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 Entity relationship diagrams (ERDs)  Data flow diagrams (DFDs)  State (transition) diagrams  Screen prototyping (story-boards) Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

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 Repetitive process  Rudimentary version of system is built  Replaces or augments SDLC  Develops more concrete specifications for ultimate system  Allows user to sees requirements converted to system - will ask for modifications as needed Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.24

 Most useful when: › User requirements are not clear › Designs are complex and require concrete form to evaluate fully › History of communication problems between analysts and users › Tools are readily available to build prototype Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.25

 Drawbacks › Tendency to avoid formal documentation › Sharing data with other systems is often not considered › Systems Development Life Cycle (SDLC) checks are often bypassed › User may misunderstand complexity of SD process Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall 5.26

 Use-case modeling  Object modeling – class diagrams  Relationship diagrams  Generalization/Abstraction models  Aggregation models  State diagrams  Sequence diagrams Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

A.28

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 Aggregation › A part-of relationship between a component object and an aggregate object Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall A.32

Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall A.33