Page 240 - 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

)NCOMPLETE 4RACEABILITY -AY 2ESULT IN )NEFFICIENCY
/N A MEDICAL PROJECT A DOCTOR WAS ASKED TO WRITE A USE CASE DOCUMENT
EXPLAINING HOW ORDERS WERE USED TO SCHEDULE OPERATIONS AT HOSPITALS
!FTER SPENDING SEVERAL WEEKS CREATING THE DOCUMENT HE DISCOVERED
THAT THE REQUESTED USE CASE ALREADY EXISTED BUT HAD NO TRACES TO OR FROM
IT AND THEREFORE IT WAS hINVISIBLEv TO ANALYSTS

IS TO DEFINE A METAMODEL AND THEN DERIVE A TRACE STRATEGY FROM THE
METAMODEL 4HE h6v MODEL APPROACH TO DEFINING TRACEABILITY IS OFTEN
USED WHERE THERE ARE SIGNIFICANT REGULATORY CONCERNS AND IS ALMOST
ALWAYS USED WHEN PRODUCT DEVELOPMENT IS OUTSOURCED 4HE METAMODEL
APPROACH IS TYPICALLY USED WHERE THERE ARE MANY DISPARATE SOURCES OF
REQUIREMENTS OR THE 2% PROCESS IS RELATIVELY COMPLEX
4HE LEFT SIDE OF THE h6v MODEL IS CONCERNED WITH REQUIREMENTS
DESIGN AND IMPLEMENTATION AND THE RIGHT SIDE DEALS WITH TESTING !T
THE TOP OF THE h6v MODEL THE REQUIREMENTS AND ACCEPTANCE TEST PLAN
ARE ASSOCIATED WITH TRACES -OVING DOWN THE h6v MODEL THE TRACES
CONNECT LOWER LEVEL REQUIREMENTS MORE HIGHLY DETAILED WITH
CORRESPONDING TESTS AND AT THE VERY BOTTOM UNITS OR COMPONENTS ARE
ASSOCIATED WITH THEIR UNIT TEST PLANS

-EASUREMENT AND -ETRICS
4HE APPLICATION OF MEASUREMENT PRACTICES TO OBTAIN METRICS IS A TECHNIQUE
FOR EFFECTIVELY MANAGING THE SOFTWARE DEVELOPMENT AND MAINTENANCE
PROCESS ;*ONES = ;-OELLER ET AL = 4HE ORIGINS OF SOFTWARE AND
SYSTEM MEASUREMENTS ARE GROUNDED IN CODE COMPLEXITY MEASURES
;-C#ABE = SOFTWARE PROJECT COST ESTIMATION ;"OEHM = SOFTWARE
QUALITY ASSURANCE ;-OELLER = AND SOFTWARE DEVELOPMENT PROCESS
IMPROVEMENT ;"ASILI = )N 'RADY AND #ASWELL WROTE A BOOK ON
THE APPLICATION OF A MANAGEMENT BY METRICS APPROACH THAT WAS PRACTICED
AT (EWLETT 0ACKARD ;'RADY ET AL = 0ROCESS PRODUCT AND QUALITY
METRICS ARE USED FOR MONITORING AND IMPROVING A SOFTWARE DEVELOPMENT
PROCESS AND FOR MANAGING SOFTWARE DEVELOPMENT PROJECTS ;*ONES =
2EQUIREMENTS ENGINEERING HAS PRACTICES AND MEASURES THAT
ARE USED TO MEASURE THE PROGRESS OF 2% ACTIVITIES AND THE QUALITY OF
2% ARTIFACTS 4HESE 2% METRICS MAY BE USED TO PROVIDE GUIDANCE
ON IMPROVING THE 2% PROCESS 4HEY MAY BE APPLIED ACROSS THE FULL
LIFE CYCLE OR APPLIED TO SPECIFIC PHASES OF DEVELOPMENT OR TO SPECIFIC
2% ARTIFACTS