Page 281 - Software and Systems Requirements Engineering in Practice

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v 0ROTOTYPING SHOULD NOT CONTINUE FOR AN EXTENDED PERIOD OF
TIME WITHOUT SPECIFIC SELECTIONS AMONG THE ALTERNATIVES
#ONCURRENT ANALYSIS OR DEVELOPMENT OF MULTIPLE VARIATIONS
TENDS TO QUICKLY INCREASE THE COMPLEXITY OF INTERACTIONS AND
INCREASES THE RISKS OF UNIDENTIFIED PROBLEMS IN THE DESIGN
4HUS THE REQUIREMENTS DECISION MAKING SHOULD BE TIME
BOXED SO THAT PROJECT PROGRESS CAN CONTINUE
v -ULTIPLE FEATURES CAN BE IMPLEMENTED AND REVIEWED WITHIN A
SINGLE DEVELOPER 2% TEAM 4HIS WAY IF SOME FEATURES ARE
BLOCKED WAITING FOR FEEDBACK THE STAFF CAN REDIRECT THEIR
EFFORTS TO OTHER FEATURES
v 4HE OUTPUT OF PROTOTYPING IS CONSIDERED TO BE A THROWAWAY
SINCE NO EMPHASIS IS PUT ON ARCHITECTING AND DESIGNING THE
IMPLEMENTATION FOR ANYTHING MORE THAN THE CURRENTLY KNOWN
SCOPE OF THE REQUIREMENTS 3INCE THE REQUIREMENTS ARE EVOLVING
THE NORMAL ACTIVITIES INVOLVED WITH DEVELOPING A MAINTAINABLE
PRODUCT WOULD LIKELY BE A WASTEFUL EFFORT (OWEVER WITHIN
THE CONTEXT OF THE KNOWN REQUIREMENTS AND EXPECTED EVOLUTION
THE ARCHITECTURE OF THE PROTOTYPE SHOULD SUPPORT QUICK
REFACTORING AND EVOLUTION
)DENTIFYõANDõ%LIMINATEõ3TAKEHOLDERõ#ONFLICTS
4HERE ARE NUMEROUS SOURCES OF CONFLICT IN SYSTEMS DEVELOPMENT
PROJECTS 3TAKEHOLDERS MAY WANT THE SYSTEM TO SERVE THEIR
INCOMPATIBLE INTERESTS 4HE NEEDS OF INDIVIDUAL STAKEHOLDERS MUST
ALWAYS BE BALANCED WITH THE GOAL OF OPTIMIZING THE EFFORT AND RESOURCES
NEEDED TO DEVELOP AND DEPLOY THE SYSTEM 7E WANT TO IDENTIFY
INCOMPATIBLE STAKEHOLDER REQUESTS AS EARLY AS POSSIBLE IN THE PROJECT
IN ORDER TO SUPPORT THE EVOLUTION OF THE INDIVIDUAL REQUESTS TOWARD A
SET OF COMPATIBLE REQUIREMENTS &OR EXAMPLE THE REQUESTS OF INSURANCE
COMPANIES AND MEDICAL PROVIDERS IN ELECTRONIC PATIENT RECORDS ARE
OFTEN INCOMPATIBLE WHEN IT COMES TO BILLING AND APPROVAL INFORMATION
YET THEY ARE STAKEHOLDERS THAT CAN BENEFIT FROM THE INTRODUCTION OF A
SHARED FORMAT 0ATIENT PRIVACY ISSUES PLAY A ROLE IN WHAT INFORMATION
BECOMES VISIBLE TO THE OTHER STAKEHOLDERS AND WHEN
4HE CONSTRUCTION OF A USE CASE WITH CONFLICTING REQUIREMENTS CAN
START FROM AN AGREED HIGH LEVEL SUNNY DAY SCENARIO 3TAKEHOLDERS ARE
PROMPTED TO EXPAND THE SCENARIO WITH SPECIFIC DETAILS RELATED TO THE
ACTORS AND EVENTS !S THE LEVEL OF DETAIL INCREASES CONFLICTS ARE LIKELY TO
MANIFEST THEMSELVES IN THE FORM OF DATA TO BE SHOWN OR HIDDEN REQUESTS
FOR DIFFERENT ACTION SEQUENCES AND DIFFERENCES IN THE AVAILABILITY AND
VISIBILITY OF REQUIRED ACTIONS OR DATA VIEWS !NOTHER PRACTICE FOR
COLLECTING INCOMPATIBLE REQUIREMENTS INFORMATION IS TO ELICIT FROM THE
STAKEHOLDERS THEIR EXPECTATIONS OF WHERE THE CONFLICTS ARE SINCE MANY
OF THEM ARE LIKELY TO BE ALREADY KNOWN 4HAT INFORMATION CAN BE USED
TO GUIDE THE TARGETED PROCESS OF IDENTIFYING SPECIFIC CONFLICTS