Page 271 - 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

ILL WAS WORKING WITH A GROUP OF STAKEHOLDERS WITH WHOM HE
WAS HAVING A DIFFICULT TIME GETTING DECISIONS AND CLARIFICATIONS
"ABOUT THEIR NEW PRODUCT REQUIREMENTS (E BEGAN TO REALIZE THAT
THE REASON THEY WERE SO RELUCTANT TO PRECISELY DEFINE THE REQUIREMENTS
WAS THAT THEY DID NOT KNOW WHAT THEY WANTED 4HE PRODUCT WAS NEW
TO THE BUSINESS AND THE STAKEHOLDERS DID NOT HAVE A CLEAR VISION OF
WHAT THE PRODUCT SHOULD DO
"ILL SUGGESTED THAT AN APPROACH TO DEFINE THE REQUIREMENTS FOR
THIS NEW PRODUCT COULD BE TO QUICKLY DEVELOP A PROTOTYPE OF THE USER
INTERFACE OF THE NEW PRODUCT THAT COULD BE EVALUATED BY THE
STAKEHOLDERS (E FOUND THAT ALTHOUGH THEY DID NOT KNOW WHAT THEY
WANTED THEY COULD MORE EASILY DETERMINE WHAT THEY DID NOT WANT
)MPLEMENTING A USER INTERFACE THAT THE STAKEHOLDERS COULD NAVIGATE
SEEMED TO BE A GOOD WAY TO DEFINE THE PRODUCT REQUIREMENTS AND
COLLECT FEEDBACK FROM THE STAKEHOLDERS 3INCE "ILL WAS ABLE TO QUICKLY
CHANGE THE PROTOTYPE USER INTERFACE AND SHOW THE STAKEHOLDERS A
NUMBER OF DIFFERENT OPTIONS THEY BEGAN TO MAKE GOOD PROGRESS ON
REQUIREMENTS DEFINITION /VER TIME THE PROTOTYPE BECAME THE PRIMARY
ARTIFACT FOR DESCRIBING THE DESIRED FEATURES OF THE NEW PRODUCT
4HIS CHAPTER IDENTIFIES SOME REQUIREMENTS ELICITATION AND
EVOLUTION CHALLENGES AND SHOWS HOW RAPID DEVELOPMENT PRACTICES
CAN BE USED TO HELP STAKEHOLDERS EVOLVE THE REQUIREMENTS 3OMETIMES
THE MANY STAKEHOLDERS OF A COMPLEX SYSTEM LACK A COMMON AND
UNAMBIGUOUS REPRESENTATION OF THE SYSTEM REQUIREMENTS 7HILE
ARCHITECTS AND DEVELOPERS OFTEN FAVOR USING REQUIREMENTS MODELS AND
REQUIREMENTS ANALYSTS MAY PREFER WORKING WITH TEXT DESCRIPTIONS
DOMAIN EXPERTS OR CLIENTS OFTEN NEED REPRESENTATIONS CLOSER TO THE
REALIZATION OF A PRODUCT "ASED ON OUR EXPERIENCE WITH PROJECTS IN
MEDICAL COMMUNICATIONS AND AUTOMATION DOMAINS WE IDENTIFY
PROTOTYPING PRACTICES THAT CAN RESULT IN RAPID REQUIREMENTS EVOLUTION
AND RESOLUTION

õ "ACKGROUND

2EQUIREMENTS ELICITATION AND ANALYSIS ARE VERY MUCH PEOPLE ORIENTED
ACTIVITIES 3TAKEHOLDERS ARE ENCOURAGED TO SHARE THEIR VISION OF THE
NEW PRODUCT UNDERSTAND EACH OTHER S VIEWPOINTS NEGOTIATE TRADEOFFS
AND EVENTUALLY COME UP WITH A COMMON VIEW OF THE FEATURES OF A
PRODUCT SUCH THAT IT WILL BE COMPETITIVE IN THE MARKET !S LONG AS THE
REQUIREMENTS CAN BE INTERPRETED IN MORE THAN ONE WAY THEIR AMBIGUITY
CREATES VARIOUS RISKS TO THE PRODUCT DEVELOPMENT
)T S DIFFICULT TO UNAMBIGUOUSLY RETRIEVE AND INTERPRET IDEAS
FROM ANOTHER PERSON WITHOUT FIRST CONVERTING THEM INTO A SHARED
REPRESENTATIONAL MEDIUM ;"ERRY ET AL = 4HIS MEDIUM IS MOST
COMMONLY A HUMAN LANGUAGE AND IN SOME CASES MORE FORMAL
TEXTUAL OR MODELING REPRESENTATIONS ARE USED 4HE LESS FORMAL THE