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Acquiring COTS software selection requirements

Commercial off the shelf software can save development time and money if you can find a package that meets your customers needs. The authors propose a model for matching COTS product features with user requirements. To support requirements acquisition for selecting commercial off the shelf products, we propose a method we used recently for selecting a complex COTS software system that had to comply with over 130 customer requirements. The lessons we learned from that experience refined our design of PORE (procurement oriented requirements engineering), a template based method for requirements acquisition. We report 11 of these lessons, with particular focus on the typical problems that arose and solutions to avoid them in the future. These solutions, we believe, extend state of the art requirements acquisition techniques to the component based software engineering process.

Can Requirements Be Creative? Experiences with an Enhanced Air Space Management System

Requirements engineering is a creative process in which stakeholders work together to create ideas for new software systems that are eventually expressed as requirements. This paper reports a workshop that integrated creativity techniques with different types of use case and system context modeling to discover stakeholder requirements for EASM, a future air space management software system to enable the more effective, longer-term planning of UK and European airspace use. The workshop was successful in that it provided a range of outputs that were later assessed for their novelty and usefulness in the final specification of the EASM software. The paper describes the workshop structure, gives examples of outputs from it, and uses these results to answer 2 research questions about the utility of creativity techniques and workshops that had not been answered in previous research.

Guiding parallel requirements acquisition and COTS software selection

This paper proposes a new process to address the lack of guidance for acquiring requirements to enable evaluation of commercial off-the-shelf (COTS) software. The process is part goal-driven and part context-driven, in that it exploits models of the candidate COTS software as well as process goals to guide a requirements engineering team. The paper demonstrates the approach with selection of a commercial electronic mail system. It also describes a prototype software tool currently under development, and outlines future research directions to extend and evaluate the approach.

The Limitations of Current Decision-Making Techniques in the Procurement of COTS Software Components

The fundamentals of good decision-making are, first, a clear understanding of the decision itself and second the availability of properly focused information to support the decision. Decision-making techniques help with both these problems. However, the techniques should be thought of as aids to decision-making and not the substitutes for it. Numerous decision-making techniques have been proposed as effective methods of ranking software products for selection for use as components in large-scale systems. Many of these techniques have been developed and successfully applied in other arenas and have been either used directly or adapted to be applied to COTS product evaluation and selection. This paper will show that many of these techniques are not valid when applied in this manner. We will describe an alternate requirements-driven technique that could be more effective.

Exploring how to use scenarios to discover requirements

This paper investigates the effectiveness of different uses of scenarios on requirements discovery using results from requirements processes in two projects. The first specified requirements on a new aircraft management system at a regional UK airport to reduce its environmental impact. The second specified new work-based learning tools to be adopted by a consortium of organizations. In both projects scenarios were walked through both in facilitated workshops and in the stakeholders’ workplaces using different forms of a scenario tool. In the second project, scenarios were also walked through with a software prototype and creativity prompts. Results revealed both qualitative and quantitative differences in discovered requirements that have potential implications for models of scenario-based requirements discovery and the design of scenario tools.

Rethinking Process Guidance for Selecting Software Components

This paper reports the results of ongoing research into compo-nent-based software engineering (CBSE) in the European banking sector as part of the EU-funded BANKSEC project. The importance of complex non-functional requirements such as dependability and security presents new challenges for CBSE. The paper presents BANKSECs vision of an integrated software tool that will provide process advice for component procurement teams who are tackling these new problems. The basis for this process guidance is a situation meta-model that enables the software tool to infer properties about the current status of the selection process and recommend process guidance relevant to this situation.

On the engineering of systems of systems: Key challenges for the Requirements Engineering community

Software intensive systems of the future will be ultra large-scale systems of systems. Systems of Systems Engineering focuses on the interoperation of many independent, self-contained constituent systems to achieve a global need. The scale and complexity of systems of systems posses unique challenges for the Requirements Engineering community. Current requirements engineering techniques are inadequate in addressing these challenges and new concepts, methods, techniques, tools and processes are required. This paper identifies some immediate key challenges for the Requirements Engineering community that need to be scoped and describes some roadmapping activities that aim to address these challenges.

Automatically generating requirements from i * models: experiences with a complex airport operations

Research undertaken in RESCUE to bridge the gap between both the model based specification and textual representation of requirements, showed that manually applying requirements generation patterns to i* system models could provide requirements engineers with productivity gains. This paper reports an extension to the RESCUE process in which a revised set of patterns was implemented within our REDEPEND goal modelling tool and trialled through a requirements engineering project for a complex airport operations system. The paper describes how these patterns were applied automatically to i* models in REDEPEND to generate textual candidate requirement statements, the results of this application, the benefits of the approach to the project, and our ongoing research in this area to improve productivity in large-scale requirements engineering projects.

Exploring Scenario Forms and Ways of Use to Discover Requirements on Airports that Minimize Environmental Impact

This scientific evaluation paper investigates the effectiveness of different scenario forms and uses on requirements discovery. Lt reports results from the application of scenario tools during the specification of requirements on socio-technical systems to improve the environmental impact of aircraft operations at a regional UK airport. Stakeholders walked through scenarios in both text and visual simulation form, and discovered requirements during workshops and whilst observing actors in their workplace. Results revealed both qualitative and quantitative differences in discovered requirements that have potential implications for models of scenario-based requirements discovery and the design of scenario tools.

Identifying top challenges for international research on requirements engineering for systems of systems engineering

Due to an increasingly connected society and industry, our modern societal world and all industry sectors now increasingly depend on large-scale complex Systems of Systems (SoS). The emerging interdisciplinary area of SoS and Systems of Systems Engineering (SoSE) is largely driven by societal needs including public services such as health, transport, water, energy, food security, etc. The scale, complexities and challenges presented by SoS require us to go beyond traditional Requirements Engineering (RE) approaches. However, as is evident from publications in major Requirements Engineering conferences and journals, no significant effort has been expedited towards addressing specific RE issues for Systems of Systems Engineering. This panel explores key RE challenges in Systems of Systems Engineering, specifically, the areas in which the international RE community need to focus its research, and the approaches that are most likely to meet these challenges effectively. We first introduce Systems of Systems Engineering and outline key characteristics of SoS. We conclude by arguing that there is an urgent need for the global RE community to develop new ways of thinking, new capabilities and possibly a new science as a key mechanism for addressing requirements complexities posed by Systems of Systems.