Page 275 - Software and Systems Requirements Engineering in Practice

ç ç 3 O F T W A R E ç ç 3 Y S T E M S ç 2 E Q U I R E M E N T S ç % N G I N E E R I N G ç ) N ç 0 R A C T I C E

TO IDENTIFY DOMAIN INCONSISTENCIES OF A GLOBAL NATURE /NCE THE
REQUIREMENTS ARE BETTER UNDERSTOOD ON A GLOBAL LEVEL BY THE
STAKEHOLDERS THERE IS MORE OPPORTUNITY FOR CONFLICT IDENTIFICATION
AND SUBSEQUENT NEGOTIATION ABOUT PRIORITIZATION AND TRADEOFFS
!DDITIONALLY THE PROTOTYPES CAN REPRESENT THE VIABLE IMPLEMENTATION
OPTIONS 4HIS HELPS THE DESIGNERS BETTER QUANTIFY THE RISKS OF
IMPLEMENTATION CHOICES AND GIVES STAKEHOLDERS HANDS ON EXPERIENCE
WITH SUCH CHOICES

"RIDGEõTHEõ3KILLSõOFõ3TAKEHOLDERSõANDõ$EVELOPERS
3TAKEHOLDERS OFTEN KNOW WHAT THEY WANT A NEW SYSTEM TO DO BUT THEY
DON T KNOW HOW TO IMPLEMENT THE FEATURES $EVELOPERS KNOW HOW TO
IMPLEMENT NEW SYSTEMS BUT THEY RARELY HAVE A FULL UNDERSTANDING OF
WHY A GIVEN SOLUTION IS CHOSEN 4ECHNICAL SKILLS PLAY AN IMPORTANT ROLE
IN DETERMINING AN OPTIMAL IMPLEMENTATION APPROACH
$ESPITE THE LACK OF CLARITY ABOUT THE CONSTRAINTS AND CAPABILITIES OF
AVAILABLE TECHNOLOGIES STAKEHOLDERS COMMONLY SPECIFY HOW THEIR NEEDS
SHOULD BE SATISFIED INSTEAD OF CONCENTRATING ON A CLEAR DESCRIPTION OF
WHAT THESE NEEDS ARE /NCE A REQUEST IS SPECIFIED AS A DESIRED SOLUTION
IT CREATES CONSTRAINTS THAT MAY LIMIT THE ALTERNATIVES FOR THE ENTIRE
SYSTEM
-ANY SOFTWARE DEVELOPERS LACK BROAD DOMAIN AND BUSINESS
KNOWLEDGE SINCE THEY TEND TO CONCENTRATE ON TECHNOLOGY CENTRIC
WORK *OB MOBILITY IN THE SOFTWARE INDUSTRY IS RELATIVELY HIGH AND
DEVELOPERS OFTEN JUMP ACROSS INDUSTRIES AND DOMAINS THUS MAKING
THEIR TECHNOLOGY KNOWLEDGE THEIR MOST PORTABLE ASSET !S A
CONSEQUENCE DEVELOPERS MAY NOT HAVE THE REQUISITE DOMAIN INSIGHTS
TO BE ABLE TO INTERNALLY IDENTIFY BUSINESS RELATED SHORTCOMINGS IN THE
SPECIFICATIONS REGARDLESS OF THE REPRESENTATION METHODS USED !S AN
EXAMPLE SPECIFYING THAT A MONEY TRANSFER REQUIRES AN AMOUNT IS A
TECHNICAL ISSUE BUT UNDERSTANDING THAT THE TRANSFER HAS A DIFFERENT
IMPACT ON SAVINGS OR LOAN ACCOUNTS IS A BUSINESS ISSUE 0ROTOTYPES
PROVIDE A LANGUAGE FOR BOTH STAKEHOLDERS AND DEVELOPERS TO EXPRESS
THEIR CAPABILITIES ALTERNATIVE SOLUTIONS PROPOSALS AND REQUESTS

#APTUREõ$ETAILEDõ2EQUIREMENTS
(IGH LEVEL REQUIREMENTS OFTEN ABSTRACT AWAY SOME ASPECTS OF A
SYSTEM IN THE EFFORT TO SIMPLIFY THE REPRESENTATION 2EQUIREMENTS
ENGINEERING BEST PRACTICES SUGGEST THAT REQUIREMENTS SHOULD BE
IMPLEMENTATION INDEPENDENT SO IT OFTEN BECOMES EASY TO OVERLOOK
IMPLEMENTATION RELATED ISSUES 3OMETIMES DOMAIN RELATED SPECIAL
CASES ARE OVERLOOKED $ECOMPOSITION OF HIGH LEVEL REQUIREMENTS
INTO LOWER LEVEL REQUIREMENTS AND SYSTEM SPECIFICATIONS IS NOT A
STRAIGHTFORWARD TECHNICAL TASK SINCE IT OFTEN INVOLVES A SIGNIFICANT
POTENTIAL FOR UNCOVERING CONFLICTS AND DIFFERENT INTERPRETATIONS OF THE
HIGH LEVEL REQUIREMENTS