Agile requirements engineering practices and challenges: an empirical study

This paper describes empirical research into agile requirements engineering (RE) practices. Based on an analysis of data collected in 16 US software development organizations, we identify six agile practices. We also identify seven challenges that are created by the use of these practices. We further analyse how this collection of practices helps mitigate some, while exacerbating other risks in RE. We provide a framework for evaluating the impact and appropriateness of agile RE practices by relating them to RE risks. Two risks that are intractable by agile RE practices emerge from the analysis. First, problems with customer inability and a lack of concurrence among customers significantly impact agile development. Second, risks associated with the neglecting non‐functional requirements such as security and scalability are a serious concern. Developers should carefully evaluate the risk factors in their project environment to understand whether the benefits of agile RE practices outweigh the costs imposed by the challenges.     

A theory of distances in software engineering

ContextCoordinating a software project across distances is challenging. Even without geographical and time zone distances, other distances within a project can cause communication gaps. For example, organisational and cognitive distances between product owners and development-near roles such as developers and testers can lead to differences in understanding and interpretation of the business requirements. Applying good software development practices, known to enhance alignment and coordination within development projects, can alleviate these challenges.ObjectiveThe aim of our research is to identify and describe underlying factors which can explain why certain practices support aligning and coordinating software development projects.MethodWe have inductively generated a theory analysing empirical data consisting of 15 interviews from 5 different companies. The systematic and iterative analysis was based on an initial hypothesis that distances affect development, and on results from previous research.ResultsWe present a theory of distances that explains how practices improve the communication within a project by impacting distances between people, activities and artefacts. We also present a theoretical model of how specific alignment practices affect different types of distances.ConclusionsThe results provide a basis for further research and can be used by software organisations to improve on software practice.     

RE challenges in multi-site software development organisations

The increasing globalisation of the software industry demands an investigation of requirements engineering (RE) in multi-site software development organisations. Requirements engineering is a task difficult enough when done locally—but it is even more difficult when cross-functional stakeholder groups specify requirements across cultural, language and time zone boundaries. This paper reports on a field study that investigated RE challenges introduced by the stakeholders' geographical distribution in a multi-site organisation. The goal was to examine RE practices in global software development, and to formulate recommendations for improvement as well as to provide directions for future research on methods and tools. Based on the empirical evidence, we have constructed a model of how remote communication and knowledge management, cultural diversity and time differences negatively impact requirements gathering, negotiations and specifications. Findings reveal that aspects such as a lack of a common understanding of requirements, together with a reduced awareness of a working local context, a trust level and an ability to share work artefacts significantly challenge the effective collaboration of remote stakeholders in negotiating a set of requirements that satisfies geographically distributed customers. The paper concludes with recommendations for improving RE practices in this setting.

A methodology for the selection of requirements engineering techniques

The complexity of software projects as well as the multidisciplinary nature of requirements engineering (RE) requires developers to carefully select RE techniques and practices during software development. Nevertheless, the selection of RE techniques is usually based on personal preference or existing company practice rather than on characteristics of the project at hand. Furthermore, there is a lack of guidance on which techniques are suitable for a certain project context. So far, only a limited amount of research has been done regarding the selection of RE techniques based on the attributes of the project under development. The few approaches that currently exist for the selection of RE techniques provide only little guidance for the actual selection process. We believe that the evaluation of RE techniques in the context of an application domain and a specific project is of great importance. This paper describes a Methodology for Requirements Engineering Techniques Selection (MRETS) as an approach that helps requirements engineers select suitable RE techniques for the project at hand. The MRETS has three aspects: Firstly, it aids requirements engineers in establishing a link between the attributes of the project and the attributes of RE techniques. Secondly, based on the evaluation schema proposed in our research, MRETS provides an opportunity to analyze RE techniques in detail using clustering. Thirdly, the objective function used in our approach provides an effective decision support mechanism for the selection of RE techniques. This paper makes contributions to RE techniques analysis, the application of RE techniques in practice, RE research, and software engineering in general. The application of the proposed methodology to an industrial project provides preliminary information on the effectiveness of MRETS for the selection of RE techniques.     

Weil Aufwand wichtig ist!

Project effort is critical for the success of software development projects. It has a major impact on whether constraints in time and budget can be complied with. But although requirements affect project effort, requirements engineering (RE) methods are not capable of assessing project effort. In this paper, we present our mapping model for assessing project effort (MMAPE). MMAPE incorporates into RE the assessment of project effort resulting from requirements for software development projects. It maps semantics of the RE method KAOS onto structures that are counted in function point analyses. We applied MMAPE in a case study on a software development project within a large financial institution. The validity of MMAPE is supported, since we found throughout consistent statements between information provided by MMAPE and data gathered from the case.     

Impediments to requirements engineering during global software development

Developing software when team members are located in widely distributed geographic locations poses many challenges for developers, particularly during the requirements engineering (RE) phase. Using a case study of a large software development project with users located in the UK and software developers from an international software house based in New Zealand, the paper argues that while global RE using electronic communication media may be desirable in achieving economy of resources, social and cultural aspects of RE need to be considered so that lasting relationships with clients may be formed, and RE activities achieved. The main impediments to the process of RE during global software development are communication resulting from differences in shared meanings and context associated with the following: distribution of the clients and the development team; distribution of the development team; cultural differences between the clients and the development team; and cultural differences among the development team.     

The impact of agile practices on communication in software development

Agile software development practices such as eXtreme Programming (XP) and SCRUM have increasingly been adopted to respond to the challenges of volatile business environments, where the markets and technologies evolve rapidly and present the unexpected. In spite of the encouraging results so far, little is known about how agile practices affect communication. This article presents the results from a study which examined the impact of XP and SCRUM practices on communication within software development teams and within the focal organization. The research was carried out as a case study in F-Secure where two agile software development projects were compared from the communication perspective. The goal of the study is to increase the understanding of communication in the context of agile software development: internally among the developers and project leaders and in the interface between the development team and stakeholders (i.e. customers, testers, other development teams). The study shows that agile practices improve both informal and formal communication. However, it further indicates that, in larger development situations involving multiple external stakeholders, a mismatch of adequate communication mechanisms can sometimes even hinder the communication. The study highlights the fact that hurdles and improvements in the communication process can both affect the feature requirements and task subtask dependencies as described in coordination theory. While the use of SCRUM and some XP practices facilitate team and organizational communication of the dependencies between product features and working tasks, the use of agile practices requires that the team and organization use also additional plan-driven practices to ensure the efficiency of external communication between all the actors of software development.

Agile Requirements Engineering Practices: An Empirical Study

An analysis of data from 16 software development organizations reveals seven agile RE practices, along with their benefits and challenges. The rapidly changing business environment in which most organizations operate is challenging traditional requirements-engineering (RE) approaches. Software development organizations often must deal with requirements that tend to evolve quickly and become obsolete even before project completion. Rapid changes in competitive threats, stakeholder preferences, development technology, and time-to-market pressures make prespecified requirements inappropriate.     

An exploratory study of architectural effects on requirements decisions

The question of the “manner in which an existing software architecture affects requirements decision-making” is considered important in the research community; however, to our knowledge, this issue has not been scientifically explored. We do not know, for example, the characteristics of such architectural effects. This paper describes an exploratory study on this question. Specific types of architectural effects on requirements decisions are identified, as are different aspects of the architecture together with the extent of their effects. This paper gives quantitative measures and qualitative interpretation of the findings. The understanding gained from this study has several implications in the areas of: project planning and risk management, requirements engineering (RE) and software architecture (SA) technology, architecture evolution, tighter integration of RE and SA processes, and middleware in architectures. Furthermore, we describe several new hypotheses that have emerged from this study, that provide grounds for future empirical work. This study involved six RE teams (of university students), whose task was to elicit new requirements for upgrading a pre-existing banking software infrastructure. The data collected was based on a new meta-model for requirements decisions, which is a bi-product of this study.     

Requirements communication and balancing in large-scale software-intensive product development

ContextSeveral industries developing products on a large-scale are facing major challenges as their products are becoming more and more software-intensive. Whereas software was once considered a detail to be bundled, it has since become an intricate and interdependent part of most products. The advancement of software increases the uncertainty and the interdependencies between development tasks and artifacts. A key success factor is good requirements engineering (RE), and in particular, the challenges of effectively and efficiently coordinating and communicating requirements.ObjectiveIn this work we present a lightweight RE framework and demonstrate and evaluate its industrial applicability in response to the needs of a Swedish automotive company for improving specific problems in inter-departmental requirements coordination and communication in large-scale development of software-intensive systems.MethodA case study approach and a dynamic validation were used to develop and evaluate the framework in close collaboration with our industrial partner, involving three real-life cases in an ongoing car project. Experience and feedback were collected through observations when applying the framework and from 10 senior industry professionals in a questionnaire and in-depth follow-up interviews.ResultsThe experience and feedback about using the framework revealed that it is relevant and applicable for the industry as well as a useful and efficient way to resolve real problems in coordinating and communicating requirements identified at the case company. However, other concerns, such as accessibility to necessary resources and competences in the early development phases, were identified when using the method, which allowed for earlier pre-emptive action to be taken.ConclusionOverall, the experience from using the framework and the positive feedback from industry professionals indicated a feasible framework that is applicable in the industry for improving problems related to coordination and communication of requirements. Based on the promising results, our industrial partner has decided upon further validations of the framework in a large-scale pilot program.     

Understanding the use of an electronic process guide

This paper presents a case study of the installation and use of an electronic process guide within a small-to-medium software development company. The purpose of the study is to better understand how software engineers use this technology so that it can be improved and better used to support software process improvement. In the study the EPG was used to guide new processes in a software improvement programme. The use of the EPG was studied over a period of 8 months with data collected through access logs, by questionnaires and by interviews. The results show that the improvement programme was successful in improving project documentation, project management and the company's relationship with its customers. The EPG contributed to the improvement programme by providing support for the creation of templates for key project documentation, assisting with project planning and estimation and providing a forum for discussion of process and work practices. The biggest improvements that could be made to the EPG would be to provide better navigation tools including a graphical overview of the process, provide tailoring facilities, include examples and experience and link to a project management tool.     

A case study validation of a knowledge-based approach for the selection of requirements engineering techniques

Requirements engineering (RE) is a critical phase in the software engineering process and plays a vital role in ensuring the overall quality of a software product. Recent research has shown that industry increasingly recognizes the importance of good RE practices and the use of appropriate RE techniques. However, due to the large number of RE techniques, requirements engineers find it challenging to select suitable techniques for a particular project. Unfortunately, technique selection based on personal experience has limitations with regards to the scope, effectiveness and suitability of the RE techniques for the project at hand. In this paper, a Knowledge-based Approach for the Selection of Requirements Engineering Techniques (KASRET) is proposed that helps during RE techniques selection. This approach has three major features. First, a library of requirements techniques was developed which includes detailed knowledge about RE techniques. Second, KASRET integrates advantages of different knowledge representation schemata and reasoning mechanisms. Thus, KASRET provides mechanisms for the management of knowledge about requirements techniques and support for RE process development. Third, as a major decision support mechanism, an objective function evaluates the overall ability and cost of RE techniques, which is helpful for the selection of RE techniques. This paper makes not only a contribution to RE but also to research and application of knowledge management and decision support in process development. A case study using an industrial project shows the support of KASRET for RE techniques selection.

Requirements engineering—exploring the influence of power and Thai values

This paper explores the impact of Thai social status and hierarchical decision-making processes during Requirements Engineering (RE) in business information systems development projects. The paper illustrates the interaction of RE processes and national culture and shows that culture can change the way processes are implemented, rather than process changing culture. Thai culture is naturally inherent in Thai daily life and Thais bring that into their work information practices. The concepts of power in Thai culture contributes toward hierarchical forms of communication and hierarchical relationships between systems analysts and decision-making process in Thai software houses, especially during RE, where information systems (IS) requirements need to be established for further development. The research shows that power significantly influences the decision making process and the construction of social status between clients and systems analysts in Thailand. The hierarchical structure of Thai organisations also contributes to a bureaucratic, elongated decision-making process during information systems development (ISD). Understanding the influence of power in Thai culture on RE will assist multinational IS consulting organisations to select, adapt, better manage, or change RE process methodologies.     

A comparative study of software tools for user story management

ContextUser stories have become widely accepted in agile software development. Consequently, a great number of software tools that provide, inter alia, support for practices based on user stories have emerged in recent years. These tools may have different features and focus in terms of support for agile requirements engineering (RE) concepts and practices.ObjectiveThe present study aims to provide a deep insight into the current capabilities and future trends of software support for agile RE practices based on user stories.MethodA comparative qualitative study of a set of agile software tools has been conducted according to the following criteria: coverage of the key functional requirements, support for basic agile RE concepts and practices, and user satisfaction with the tool. The criteria for tool selection were: diversity of software tools, high rating on the user-stories community Web site (http://www.userstories.com), and availability for review.ResultsThe results show a generally good coverage of key functional requirements related to management of user stories and epics, high-level release planning and low-level iteration planning. On the other hand, user-role modeling and persona support have not been addressed at all, and it has been found that requirements for acceptance testing support were completely covered by only one tool. More importantly, the study has revealed significant differences in the way different tools support agile RE concepts and practices (if at all). Finally, qualitative analysis of user reviews has demonstrated that practitioners prefer tools that are easy to set up, easy to learn, easy to use, and easy to customize, over more sophisticated but simultaneously more demanding tools.ConclusionAlthough the progress that has been made since the inception of these tools is quite clear, there is still room for improvements in terms of support for various agile RE practices within a specific agile process.     

基于问题框架的计算机辅助需求工程工具的研发

问题框架(Problem Frames,PF)已经得到需求工程界的广泛重视和研究。目前,问题框架在理论基础和开发方法等方面已经有很多研究成果,但如何把它们应用到实际的软件开发项目中仍是一个有待解决的问题。本工具可帮助系统分析员实现从用户需求到软件规约的平滑和可推理的变换,从而为软件开发项目中需求的沟通、建模及分析等提供技术支持。此外,该工具产生的结果也为下一步的软件设计提供帮助。它对促进问题框架方法的进一步发展和成熟,如从研究走向实用,具有重要的推动作用。     

Are you biting off more than you can chew? A case study on causes and effects of overscoping in large-scale software engineering

ContextScope management is a core part of software release management and often a key factor in releasing successful software products to the market. In a market-driven case, when only a few requirements are known a priori, the risk of overscoping may increase.ObjectiveThis paper reports on findings from a case study aimed at understanding overscoping in large-scale, market-driven software development projects, and how agile requirements engineering practices may affect this situation.MethodBased on a hypothesis of which factors that may be involved in an overscoping situation, semi-structured interviews were performed with nine practitioners at a large, market-driven software company. The results from the interviews were validated by six (other) practitioners at the case company via a questionnaire.ResultsThe results provide a detailed picture of overscoping as a phenomenon including a number of causes, root causes and effects, and indicate that overscoping is mainly caused by operating in a fast-moving market-driven domain and how this ever-changing inflow of requirements is managed. Weak awareness of overall goals, in combination with low development involvement in early phases, may contribute to ‘biting off’ more than a project can ‘chew’. Furthermore, overscoping may lead to a number of potentially serious and expensive consequences, including quality issues, delays and failure to meet customer expectations. Finally, the study indicates that overscoping occurs also when applying agile requirements engineering practices, though the overload is more manageable and perceived to result in less wasted effort when applying a continuous scope prioritization, in combination with gradual requirements detailing and a close cooperation within cross-functional teams.ConclusionThe results provide an increased understanding of scoping as a complex and continuous activity, including an analysis of the causes, effects, and a discussion on possible impact of agile requirements engineering practices to the issue of overscoping. The results presented in this paper can be used to identify potential factors to address in order to achieve a more realistic project scope.     

Requirement-oriented risk management for incremental software development

In incremental software development (ISD) functionalities are delivered incrementally and requirements keep on evolving across iterations. The requirements evolution involves the addition of new dependencies and conflicts among functional and non-functional requirements along with changes in priorities and dependency weights. This, in turn, demands refactoring the order of development of system components to minimize the impact of these changes. Neglecting the non-functional constraints in the software development process exposes it to risks that may accumulate across several iterations. In this research work, we propose a risk management framework for ISD processes that provides an estimate of risk exposure for the project when functional features are frozen while ignoring the associations with non-functional requirements. Our framework proposes suitable risk reduction strategies that work in tandem with the risk assessment module. We also provide a tool interface for our risk management framework.

     

System requirements-OSS components: matching and mismatch resolution practices – an empirical study

Developing systems by integrating Open Source Software (OSS) is increasingly gaining importance in the software industry. Although the literature claims that this approach highly impacts Requirements Engineering (RE) practices, there is a lack of empirical evidence to demonstrate this statement. To explore and understand problems and challenges of current system requirement–OSS component matching and mismatches resolution practices in software development projects that integrate one or more OSS components into their software products. Semi-structured in-depth interviews with 25 respondents that have performed RE activities in software development projects that integrate OSS components in 25 different software development companies in Spain, Norway, Sweden, and Denmark. The study uncovers 15 observations regarding system requirements-OSS components matching and mismatch resolution practices used in industrial projects that integrate OSS components. The assessed projects focused mainly on pre-release stages of software applications that integrate OSS components in an opportunistic way. The results also provide details of a set of previously unexplored scenarios when solving system requirement–OSS component mismatches; and clarify some challenges and related problems. For instance, although licensing issues and the potential changes in OSS components by their corresponding communities and/or changes in system requirements have been greatly discussed in the RE literature as problems for OSS component integration, they did not appear to be relevant in our assessed projects. Instead, practitioners highlighted the problem of getting suitable OSS component documentation/information.     

A field study of the requirements engineering practice in Australian software industry

Empirical studies have demonstrated that requirements errors introduced during software development are most numerous in the software life-cycle, making software requirements critical determinants of software quality. This article reports an exploratory study which provides insight into industrial practices with respect to requirements engineering (RE). A combination of both qualitative and quantitative data is collected, using semi-structured interviews and a detailed questionnaire from 28 software projects in 16 Australian companies. The contribution of this RE study is threefold: Firstly, it includes a detailed examination of the characteristics of the RE activities involved in the projects. Secondly, it reconstructs the underlying practiced process models. Thirdly, it compares these models to one another and with a number of well-known process models from RE literature to give insight into the gap between RE theory and practice.     

Integration by communication: knowledge exchange in global outsourcing of product software development

Global outsourcing is a growing trend among independent software vendors. In these projects like other distributed work, distances have negative effects on communication and coordination, directly impacting performance. We present a normative model designed to address this issue by improving communication and knowledge exchange. The model consists of six distinct practices and a tool blueprint, each coming with practical guidelines. It is based in part on two case studies of Dutch software vendors who have successfully outsourced part of their activities to an Eastern European outsourcing vendor, and validated by a panel of six experts from industry and the scientific community. It is concluded that knowledge exchange in global software outsourcing is a by‐product of efforts to enhance communication and coordination, rather than specific technical solutions. By committing to sharing knowledge, emphasizing transparency and integrating the outsourcing team into their organizations, customers from the product software business can realize the benefits of global outsourcing.