Usman Wajid

Assisted Service Composition for End Users

Involving people who do not have programming background in assembling and tailoring service-based applications promises to open up access to the creativity of millions of users. An increasing number of development environments aim to do this by offering drag-and-drop visual representations connecting different service components into an assembly. In contrast to the majority of these, we did not start with the technology but with the users - service producers and consumers, and studied the core issues which should be resolved before people who are not programmers can start to assemble services into meaningful applications, over and above the presentation-level integration offered by current mash-up environments. The result is an assisted approach to service composition for end users, which uses semantic technologies to shield users from the irrelevant complexity of service technology and from the need to manually resolve dependencies between services. The approach was evaluated by a focus group of non-technical users, who ranked it highly and provided valuable suggestions for further improvements and supporting features.

End User Service Composition: Perceptions and Requirements

The idea that end users who are not programmers will one day compose software services has motivated our study of user perceptions, intuitions and requirements. This study comprised five focus groups which took place within SOA4All - an EC-funded research project aiming to bring service technology to everyone. The paper focuses on one aspect of the study - the perceptions and intuitions our users have about services in general and software services in particular, and about how to bring services together. It presents and analyses the results related to this aspect, including the results from three notational tasks. It then uses these results to derive a set of requirements about effective notations for service composition.

Provider-Composer Negotiations for Semantic Robustness in Service Compositions

Research in automating service composition is rarely concerned with service providers, apart from work in quality guarantees and contracts. This perspective is arguably valid for comparatively static and cheap web services, which do not warrant continuous involvement of their providers in the process of service procurement and use by service consumers. However, opportunities for optimisation and fine-tuning of compositions are thus missed. We have created an approach which uses automated agent-based negotiation between service composer and service providers to address the issue of semantic robustness in large-scale service compositions by preventing cases where the wrong type of data is passed on from one service to the next. Starting from a service composition template which is not semantically robust, we allow the selection of semantically robust combinations of actual services. The approach is characterised with a linear complexity and also allows service providers to tune their services to the requirements of service compositions which may be lucrative business opportunities.

On Achieving Energy Efficiency and Reducing CO 2 Footprint in Cloud Computing

With the increasing popularity of the cloud computing model and rapid proliferation of cloud infrastructures there are increasing concerns about energy consumption and consequent impact of cloud computing as a contributor to global CO2 emissions. To date, little is known about how to incorporate energy consumption and CO2 concerns into cloud application development and deployment decision models. In this respect, this paper describes an eco-aware approach that relies on the definition, monitoring and utilization of energy and CO2 metrics combined with the use of innovative application scheduling and runtime adaptation techniques to optimize energy consumption and CO2 footprint of cloud applications as well as the underlying infrastructure. The eco-aware approach involves measuring or quantifying the energy consumption and CO2 at different levels of cloud computing, using that information to create scheduling and adaptation techniques that contribute towards reducing the energy consumption and CO2 emissions, and finally testing and validating the developed solutions in a multi-site cloud environment with the help of challenging case study applications. The experimental and validation results show the potential of the eco-aware approach to significantly reduce the CO2 footprint and consequent environmental impact of cloud applications.

Negotiating Robustness in Semantic Web Service Composition

Automating Web service composition is a challenging area of Service Oriented Computing, requiring progress on a number of issues concerning the automation of control flow, the alignment of data flow, verification, execution monitoring, etc. In this paper, we focus on aligning data flow in semantic web service composition to ensure the robustness when executing the composed service by preventing any cases when the wrong type of data is passed on from one service to the next. The proposed solution is unique in that it ensures the robustness of data flow when automatically composing web services through the use of agent-based negotiation between web service providers. Starting from the semantic specification of a non-robust composition, we adapt the mechanism of Concept Abduction to compute the set of additional semantic descriptions necessary to ensure robustness of the semantic connections within the composed service. An agent-based negotiation is then used to solicit the additional semantic definitions which are required for achieving robust web service compositions.

Enhancing Enterprise Collaboration Using a Protocol for Semantic Alignment

When small and medium enterprises (SMEs) engage in collaborations, they typically rely on E-mail based communication due to limited access to modern technology. One of the key factors to enhance SME collaboration is enabling semantic interoperability at the level of emails and documents that are exchanged between collaborating enterprises. However, achieving semantic interoperability is not an easy task to accomplish. Automatic interpretation of information relies on pre-defined static ontologies shared by diverse enterprises, which in practice is difficult to establish because of the specialized nature of products and services offered by each enterprise. In this background, this paper presents an agent-based negotiation approach for enabling semantic alignment of concepts, and thus facilitating semantic interoperability between SMEs to enhance collaboration.

Energy Efficient and CO2 Aware Cloud Computing: Requirements and Case Study

Energy efficiency and CO2 awareness are globally-important issues in cloud computing. With increasing attention being paid to the environmental impact of cloud computing there are concerns about the sustainability of cloud computing model as its uptake increases. In this respect, we consider it useful to provide a snapshot of the requirements for energy efficient and CO2 aware cloud computing to allow the conception and development of new techniques and approaches in this area. Further, we present a case study approach for energy efficient cloud sourcing that aims to build on these requirements.

Collaborative Trust in Multi-agent System

In an increasingly competitive environment like Virtual Organization; software agents need to be very flexible towards any changes in order to achieve sustainable growth and improve competency. Another way to address this is to form collaboration amongst the agents themselves. Although being in an openly distributed environment where almost anyone can do business with everyone; it is never that straightforward. One of the major issues in performing any kind of collaboration in such environment is who can be trusted? Therefore this novel work focuses on developing a collaborative trust framework in corresponding to this need for facilitating agents in identifying its potential collaborative partner.

Optimizing Energy Efficiency in the Cloud Using Service Composition and Runtime Adaptation Techniques

This paper describes an approach for service composition optimization and its application in cloud computing to streamline resource usage that in turn contributes towards energy efficiency. The suitability and usefulness of the approach is evaluated by experimentation. In the experiments, physical hosts at various cloud sites represent candidate services that are brought together in a composition to satisfy the requirements of applications. The composition is optimized based on functional and non-functional criteria to determine a set of cloud services representing energy efficient deployment configurations. We also propose a runtime adaptation model that can help in minimizing energy consumption of cloud applications at runtime.

Agent Interaction Protocols and Flexible Agent Interaction in Dynamic Environments

Software agents are often seen as flexible goal-driven software technology suitable for dynamic environments such as business ecosystems. The inherently open and unpredictable nature of such environments, however, renders unsuitable many widely used agent design mechanisms, such as agent interaction protocols. This paper describes an approach which addresses the need for flexible inter-agent interactions. Our approach gives agents freedom of action and enhances their ability to respond to unexpected events in open environments. We base our argument on the limitations of protocol-based approaches used to formalize agent interaction. We then investigate the possibility of protocol-free agent interaction to enable flexible operation of agent systems in dynamic environments