Goals capture, at different levels of abstraction, the various objectives the system under consideration should achieve.

Requirements engineering is concerned with the elicitation of high-level goals to be achieved by the envisioned system, the refinement of such goals and their operationalization into specifications of services and constraints, and the assignment of responsibilities for the resulting requirements to agents such as humans, devices, and software. Requirements engineering processes often result in goals, requirements and assumptions about agent behavior that are too ideal; some of them are likely to be not satisfied from time to time in the running system due to unexpected agent behavior. The lack of anticipation of exceptional behaviors results in unrealistic, unachievable and/or incomplete requirements. As a consequence, the software developed from those requirements will not be robust enough and will inevitably result in poor performance or failures, sometimes with critical consequences on the environment. The paper presents formal techniques for reasoning about obstacl...

Requirements engineering (RE) is concerned with the identification of the goals to be achieved by the envisioned system, the operationalization of such goals into services and constraints, and the assignment of responsibilities for the resulting requirements to agents such as humans, devices, and software. The processes involved in RE include domain analysis, elicitation, specification, assessment, negotiation, documentation, and evolution. Getting highquality requirements is difficult and critical. Recent surveys have confirmed the growing recognition of RE as an area of utmost importance in software engineering research and practice. The paper presents a brief history of the main concepts and techniques developed to date to support the RE task, with a special focus on modeling as a common denominator to all RE processes. The initial description of a complex safetycritical system is used to illustrate a number of current research trends in RE-specific areas such as go...

The need to deal with conflicting system requirements has become increasingly important over the past several years. Often, these requirements are elastic in that they can be satisfied to a degree. The overall goal of this research is to develop a formal framework that facilitates the identification and the tradeoff analysis of conflicting requirements by explicitly capturing their elasticity. Based on a fuzzy set theoretic foundation for representing imprecise requirements, we describe a systematic approach for analyzing the tradeoffs between conflicting requirements using the techniques in decision science. The systematic tradeoff analyses are used for three important tasks in the requirement engineering process: (1) for validating the structure used in aggregating prioritized requirements, (2) for identifying the structures and the parameters of the underlying representation of imprecise requirements, and (3) for assessing the priorities of conflicting requirements. We illustrate th...

In this article we present a survey on the area of Requirements Engineering anchored on the analysis of a real life case study, the London Ambulance Service [56]. We aim at bringing to context new methods, techniques and tools that should be of help to both reaserchers and practitioners. The case study in question is of special interest in that it is available to the public and deals with a very large system, of which the software system is only a part of. The survey is divided into four topics of interest: viewpoints, social aspects, evolution and non-functional requirements. This division resulted from the work method adopted by the authors. Our main goal is to bridge recent findings in Requirements Engineering research to a real world problem. In this light, we believe this article to be an important educational device.

This paper provides a short review of contributions to a better understanding of requirements engineering arising from research at Imperial College. These contributions share a common theme - a focus on "multiple perspectives" or viewpoints. 1 Theme The development of most large and complex systems necessarily involves many people - each with their own perspective on the system defined by their skills, responsibilities, knowledge and expertise. This is particularly true where the system is a composite system, that is one which deploys a variety of different technologies (software, hardware, mechanical and so on). Inevitably, the different perspectives of those involved in the process intersect and overlap, giving rise to a requirement for coordination. The intersections are, however, far from obvious because the knowledge within each perspective is represented in different ways. Further, because development may be carried out concurrently by those involved, different perspectives may ...

Project managers and developers need to acknowledge the influence of IS stakeholders ’ perspectives and perceptions on the outcome of requirements negotiation- the essential component of requirements elicitation. This paper describes a conceptual study, which demonstrates such an influence and asserts that stakeholder perspectives, goals and issues are the key to negotiators ’ perceptions of the system requirements. Analysis of two seminal IS case studies further supports this assertion and indicates that goals, perspectives and prior experience with negotiation techniques can guide stakeholders bargaining behaviour during requirements negotiation. Our findings also show that to achieve consensus on requirements, stakeholder perspectives must be aligned or accepted by negotiating parties. Achieving alignment of perspectives, however, is quite difficult because during requirements elicitation stakeholders’ goals continually alter due to their acquisition of technical and business knowledge, development of inter-personal relationships and creation of new perceptions of issues relevant to requirements negotiation. 1.

Abstract- Recent advancements in communication systems enable the collaboration of virtual software design teams, breaking the barriers of time and distance. In this paper we address a critical aspect of the collaborative work of virtual project teams, the negotiation of requirements in software development. We present an exploratory study of the effects of multimedia communication systems on group negotiation performance and behavior. An emphasis is placed on the development of a research methodology that uses multiple methods in investigating a complex phenomenon. Contrary to the belief that face-to-face interaction increases performance, our laboratory findings suggest that groups in face-to-face meetings perform no better than video-conferenced groups; moreover, we identified a particular distributed virtual team configuration that was qualitatively more conducive to requirements negotiation than face-to-face meetings.

Abstract. This paper discusses the research methodology used in a study of requirements negotiations in geographically distributed settings. The methodology was based on a multidisciplinary paradigm that considered research methods and models from requirements engineering, soft system methodologies, group research and negotiation literature, and computer supported cooperative work. An integral part of the research methodology was the design of a laboratory study that empirically compared computer-supported distributed requirements negotiations with traditional face-to-face requirements decision meetings. The paper describes the components of the study design in the context of the research methodology, and discusses lessons learned from designing this study. Insights related to the necessity of interdisciplinary approaches to the study of RE, the intrinsic tension between control and realism of context in laboratory studies and ways in which the study brought a better understanding of a RE problem are discussed. 1.

Conflict is a common phenomenon in our daily life and as such conflict has an important impact on Requirements Engineering (RE). However, in the current RE literature, conflict is often addressed in terms of a technical issue leading to inconsistency in the requirements specification. Little attention is given to the socio-psychological aspects of the conflict. Furthermore, previous RE work typically views the resolution of conflicts in RE as a purely negotiationbased process, in which a requirements engineer acts as a representative of a developer site and negotiates with users. By drawing on the Information Systems and Conflict Resolution literature, we argue that conflict resolution in RE should be a mediated process, in which a requirements engineer acts as a mediator amongst different stakeholders. We introduce our narrative mediation theory and explain how it can be introduced into the field of RE. 1.