Page 292 - 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

v 4RADE OFF REUSE REQUIREMENTS WITH PROTOTYPE SPEED $O NOT
OVER ENGINEER THE PROTOTYPES EITHER FOR EVOLUTIONARY PURPOSES
OR FOR MAINTAINABILITY )N MANY CASES A COPY PASTE APPROACH
WORKS WELL ENOUGH TO ENABLE REQUIREMENTS ELICITATION AND
EVALUATION "UT DEVELOPERS ARE ALWAYS FREE TO DEFINE REUSABLE
COMPONENTS IF THEY EXPECT THEM TO IMPROVE THE EFFECTIVENESS
OF THE PROTOTYPING PROCESS FOR EXAMPLE WHEN A LARGE NUMBER
OF RELATED PROTOTYPES ARE BEING CONSIDERED
v $EVELOP BOTTOM UP )MPLEMENT THE PARTS AND THEN
UNDERSTAND HOW THEY COMBINE INTO THE WHOLE 4HE PRIMARY
GOAL OF RAPID PROTOTYPING IS TO CREATE A SUFFICIENTLY
UNAMBIGUOUS REPRESENTATION THAT WILL ALLOW THE STAKEHOLDERS
AND DEVELOPERS TO EVENTUALLY BETTER UNDERSTAND THE WHOLE
PICTURE )F THE WHOLE IS UNDERSTOOD AT THE START THEN
PROTOTYPING FOR REQUIREMENTS ELICITATION IS NOT NEEDED

õ 3UMMARY
0RODUCT REQUIREMENTS THAT ARE UNCLEAR OR ARE HIGHLY USER VISIBLE CAN
BE QUICKLY DEVELOPED AND VISUALIZED WITH A STORYBOARD PAIRED WITH A
RUNNING SYSTEM PROTOTYPE )MPROVED STAKEHOLDER COMMUNICATIONS
CENTERED ON THE PROTOTYPE WILL RESULT IN MORE RAPID ELICITATION AND
VALIDATION OF PRODUCT REQUIREMENTS (IGHLY CONCURRENT WORK AND
RAPID FEEDBACK KEEP THE ENTIRE SMALL TEAM ENGAGED AND FOCUSED UNTIL
THE REQUIREMENTS ARE BETTER UNDERSTOOD CORRECT AND UNAMBIGUOUS

õ $ISCUSSIONõ1UESTIONS
7HEN SHOULD WORKING PROTOTYPES BE IMPLEMENTED AS
COMPARED TO NON CODING BASED APPROACHES SUCH AS
STORYBOARDS
5NDER WHICH CONDITIONS SHOULD ONE CONSIDER REUSING
PROTOTYPE CODE FOR THE PRODUCT DEVELOPMENT AS COMPARED TO
THROWAWAY PROTOTYPES
(OW FREQUENTLY SHOULD ITERATIONS OF PROTOTYPE FEATURE
DEVELOPMENT AND REVIEW OCCUR
7HEN IS THE BEST TIME TO STOP PROTOTYPING AND MOVE ON TO
FULL SCALE PRODUCT DEVELOPMENT

2EFERENCES
"ECK + 4EST $RIVEN $EVELOPMENT "Y %XAMPLE !DDISON 7ESLEY "OSTON -!
"ERRY $ +AMSTIES % AND +RIEGER - h&ROM #ONTRACT $RAFTING TO 3OFTWARE
3PECIFICATION ,INGUISTIC 3OURCES OF !MBIGUITY v 5NIVERSITY OF 7ATERLOO