Requirements as Goals and Commitments Too - Intentional Perspectives on Information Systems Engineering - page 135

Requirements as Goals and Commitments Too

Amit K. Chopra, John Mylopoulos, Fabiano Dalpiaz, Paolo Giorgini,
and Munindar P. Singh

Abstract In traditional software engineering research and practice, requirements
are classified either as functional or non-functional. Functional requirements consist
of all functions the system-to-be ought to support, and have been modeled in terms
of box-and-arrow diagrams in the spirit of SADT. Non-functional requirements
include desired software qualities for the system-to-be and have been described
either in natural language or in terms of metrics. This orthodoxy was challenged
in the mid-90s by a host of proposals that had a common theme: all requirements
are initially stakeholder goals and ought to be elicited, modeled and analyzed as
such. Through systematic processes, these goals can be refined into specifications
of functions the system-to-be needs to deliver, while actions assigned to external
actors need to be executed. This view is dominating Requirements Engineering
(RE) research and is beginning to have an impact on RE practice. We propose a
next step along this line of research, by adopting the concept of conditional com-
mitment as companion concept to that of goal. Goals are intentional entities that
capture the needs and wants of stakeholders. Commitments, on the other hand, are
social concepts that define the willingness and capability of an actor A to fulfill a
predicate

ψ
for the benefit of actor A. In our conceptualization, goals are mapped to collections
of commitments rather than functions, qualities, or actor assignments. We motivate
the importance of the concept of commitment for RE through examples and discus-
sion. We also contrast our proposal with state-of-the-art requirements modeling and
analysis frameworks, such as KAOS, MAP, i ∗ and Tropos.

ϕ for the benefit of actor B, provided B (in return) fulfills predicate

1 Introduction

Colette Rolland is an eminent researcher, mentor and leader in the Information
Systems community thanks to a distinguished career that spans more than three