George Spanoudakis

Rule-based generation of requirements traceability relations

Abstract The support for traceability between requirement specifications has been recognised as an important task in the development life cycle of software systems. In this paper, we present a rule-based approach to support the automatic generation of traceability relations between documents which specify requirement statements and use cases (expressed in structured forms of natural language), and analysis object models for software systems. The generation of such relations is based on traceability rules of two different types. More specifically, we use requirement-to-object-model rules to trace the requirements and use case specification documents to an analysis object model, and inter-requirements traceability rules to trace requirement and use case specification documents to each other. By deploying such rules, our approach can generate four different types of traceability relations. To implement and demonstrate our approach, we have implemented a traceability prototype system. This system assumes requirement and use case specification documents and analysis object models represented in XML. It also uses traceability rules which are represented in an XML-based rule mark-up language that we have developed for this purpose. This XML-based representation framework makes it easier to deploy our prototype in settings characterised by the use of heterogeneous software engineering and requirements management tools. The developed prototype has been used in a series of experiments that we have conducted to evaluate our approach. The results of these experiments have provided encouraging initial evidence about the plausibility of our approach and are discussed in the paper.

A framework for requirents monitoring of service based systems

This paper proposes a framework for monitoring the compliance of systems composed of web-services with requirements set for th. This framework assumes systems composed of web-services that are co-ordinated by a service composition process expressed in BPEL4WS and uses event calculus to specify the properties to be monitored. The monitorable properties may include behavioural properties of a syst which are automatically extracted from the specification of its composition process in BPEL4WS and/or assumptions that syst providers can specify in terms of events extracted from this specification.

Run-time monitoring of requirements for systems composed of Web-services: initial implementation and evaluation experience

This paper describes a framework supporting the runtime monitoring of requirements for systems implemented as compositions of Web-services specified in BPEL. The requirements that can be monitored are specified in event calculus. The paper presents an overview of the framework and describes the architecture and implementation of a tool that we have developed to operationalise it. It also presents the results of a preliminary experimental evaluation of the framework.

Establishing and Monitoring SLAs in Complex Service Based Systems

In modern service economies, service provisioning needs to be regulated by complex SLA hierarchies among providers of heterogeneous services, defined at the business, software, and infrastructure layers. Starting from the SLA Management framework defined in the SLA@SOI EU FP7 Integrated Project, we focus on the relationship between establishment and monitoring of such SLAs, showing how the two processes become tightly interleaved in order to provide meaningful mechanisms for SLA management. We first describe the process for SLA establishment adopted within the framework; then,we propose an architecture for monitoring SLAs, which satisfies the two main requirements introduced by SLA establishment: the availability of historical data for evaluating SLA offers and the assessment of the capability to monitor the terms in a SLA offer.

Software package requirements and procurement

The paper outlines the problems of specifying requirements and deploying these requirements in the procurement of software packages. Despite the fact that software construction de novo is the exception rather than the rule, little or no support for the task of formulating requirements to support assessment and selection among existing software packages has been developed. We analyse the problems arising in this process and review related work. We outline the key components of a programme of research in this area.

NON-INTRUSIVE MONITORING OF SERVICE-BASED SYSTEMS

This paper presents a framework for monitoring the compliance of systems composed of Web-services with requirements set for them at runtime. This framework assumes systems composed of Web-services which are co-coordinated by a service composition process expressed in BPEL and uses event calculus to specify the requirements to be monitored. These requirements may include behavioral properties of a system which are automatically extracted from the specification of its composition process in BPEL and/or assumptions that system providers can specify in terms of events extracted from this specification.

A service discovery framework for service centric systems

An important aspect of service-centric systems (i.e. systems composed of services) is the ability to support service discovery at run-time in order to cope with unavailable or malfunctioning services. In this paper we present a framework that supports run-time service discovery. The central characteristic of this framework is the combination of components for monitoring the compliance of service-centric systems with requirements at run-time and components for discovering services at run-time. The framework uses the former components to detect violations of requirements at run-time and uses the specifications of the violated requirements to generate queries for discovering services that could substitute for malfunctioning services. It also uses queries derived from the process specification for service discovery. These queries incorporate both structural and behavioural aspects of the required services.

Monitoring WS-Agreement s: An Event Calculus–Based Approach

In this chapter, we present a framework that we have developed to support the monitoring of service level agreements (SLAs). The agreements that can be monitored by this framework are expressed in an extension of WS-Agreement that we propose. The main characteristic of the proposed extension is that it uses an event calculus–based language, called EC-Assertion, for the specification of the service guarantee terms in a service level agreement that need to be monitored at runtime. The use of EC-Assertion for specifying service guarantee terms provides a well-defined semantics to the specification of such terms and a formal reasoning framework for assessing their satisfiability. The chapter describes also an implementation of the framework and the results of a set of experiments that we have conducted to evaluate it.

Overlaps in Requirements Engineering

Although overlap between specifications—that is the incorporation of elements which designate common aspects of the system of concern—is a precondition for specification inconsistency, it has only been a side concern in requirements engineering research. This paper is concerned with overlaps. It defines overlap relations in terms of specification interpretations, identifies properties of these relations which are derived from the proposed definition, shows how overlaps may affect the detection of inconsistency; shows how specifications could be rewritten to reflect overlap relations and still be amenable to consistency checking using theorem proving; analyses various methods that have been proposed for identifying overlaps with respect to the proposed definition; and outlines directions for future research.

Plausible and adaptive requirement traceability structures

This paper presents an extension of a traceability system which automates the generation of traceability relations between textual requirement artefacts and object models using heuristic traceability rules. These rules match syntactically related terms in the textual parts of the requirements artefacts with related elements in an object model (e.g. classes, attributes, operations) and create traceability relations of different types when a match is found. The extension described in this paper measures beliefs in: (1) the ability of specific traceability rules to generate correct traceability relations, (2) the satisfiability of traceability rules by particular types of artefacts, and (3) the correctness of individual traceability relations. It also provides a mechanism with well-founded semantics for revising these beliefs on the basis of partial (and even conflicting) assessments of the relations that these rules generate provided by different users.