1. Requirements Management
Adelina Maxim

2. What is a Requirement?
What is Requirements Management?
A requirement
is a condition or capability needed by a stakeholder to solve a problem or
achieve an objective;
Requirements management
is the process by which these requirements are:
 identified,
 captured,
 organized,
 communicated and
 managed as they potentially change during the development lifecycle.

3. What is a good requirement ?
A "good" requirement is:
 atomic
address only one topic
 clear, non ambiguous
text shall be understood by everybody, no literature, no specific abbreviations, ...
avoid "generally", "may be", ... avoid vague terms like "user friendly"...
 necessary
The requirement is justified by a need
 realistic, feasible
 testable, provable
 no information about the realization
Describe "what", not "how"
Between several requirements:
 unique
no redundancies between several requirements
 consistent
no inconsistencies between requirements
 complete: all information can be found with a set of requirements
REQ1: the system stops when minimum level is reached
REQ2: minimum level is 2 Volt

4. How to write requirements:
verbs to be used
 To describe requests from customer (upper level)
shall Mandatory request of customer
example: the light shall be green
should (wished) request from customer
example: the system should address stadiums as "points of interest"
may allow optional insertion, even if not directly requested by the customer
example: the system, when it starts, may force the user to choose the language for display
 To describe external constraints or events which have an impact on
requirements or on their environment:
must External constraint (standards etc). Mandatory
example: after 20 seconds the CD must automatically be retracted according to EC laws
will Systematic External Event. Assumption
example: when battery voltage drops too low (5V), the External Battery Guard will switch off the
power
can Possible External Event
example: the power can be interrupted at any moment

5. Several levels of Requirements
C us to me r
r e q u ir e m e n t s T racing
S ys te m
I nterpretati r e q u i r e m e n t s T racing
on S o ftw a re
A llocation r e q u ir e m e n t s
Customer requirements
Expectations of the final customer (BMW, VW, Peugeot, …)
System Requirements
 Interpretation of customer requirements in SV I IS context. Based on:
 explicit customer requirements (on functions, performance, …)
implicit requirements + internal (to SV I IS) constraints (re-use of
platforms,maintenance constraints, …)
System Requirements (written by SV I IS) have to be approved by final customer
SW Requirements
The SW Requirements are described in the SW-RD (SW Requirements Document)
The interface for the SW Project as far as Requirements are concerned is SE