Tradeoff Analysis for Conflicting Software Non-Functional Requirements

Xuan Zhang,Xu Wang

doi:10.1109/access.2019.2949218

Abstract

The need for particular software non-functional requirements (NFRs) leads a project team to use specific design strategies to fulfill these NFRs. However, some of the strategies may cause deficiencies in other software NFRs. These strategies are called conflicting strategies. Making the tradeoff decision of these conflicting strategies for NFRs is crucial. Therefore, a conflicting NFRs tradeoff framework (CNTF) and the corresponding method are proposed. Firstly, the NFRs are obtained from stakeholders. Fuzzy set theory is used to express stakeholder assessments on the importance of each NFR. The assessment results are ranked using a fuzzy ranking method. Then, adapting from production theory in microeconomics, the degree of satisfaction by which NFRs are affected by conflicting strategies are plotted as tradeoff curves. Borrowing the concept from the linear programming in management science, a tradeoff method is presented to help software project teams make the best tradeoff decision for conflicting NFRs. Finally, feasibility and limitations of the CNTF are elaborated in a case study.

Highlights

Any software organization needs to consider non-functional requirements (NFRs) in order to deliver a system that complies with its stakeholder expectations [1]
Despite the methods and tradeoff results being discussed in the project team, the findings are not conclusive
We showed that further validation in more realistic cases would be conducted

Summary

INTRODUCTION

Any software organization needs to consider non-functional requirements (NFRs) in order to deliver a system that complies with its stakeholder expectations [1]. The focus of this research has been mostly on modeling and reasoning, which aims to assist software engineers in analyzing NFRs relations qualitatively. These methods describe the interdependencies, e.g., ‘‘BREAK, HURT, UNKNOWN, HELP, MAKE’’ with some legends such as ‘‘--, −, ?, +, ++’’, and describe the degree. Based on our previous work [21], the conflicting NFRs were found by using goal-oriented modeling and reasoning. (2) A conflicting NFRs tradeoff framework (CNTF) was proposed to compensate for the reasoning in goal-oriented requirements engineering.

MOTIVATION SCENARIO

TRADEOFF FOR CONFLICTING NFRS

CASE STUDY

RELATED WORK

Findings

CONCLUSION