Service Selection of Ensuring Transactional Reliability and QoS for Web Service Composition

Service-Oriented Architecture (SOA) provides a flexible framework of service composition. Using standard-based protocols, composite service can be constructed by integrating component services independently. As component services are developed by different organization and offer diverse transactional properties and QoS characteristics, it is a challenging problem how to select suitable component services which ensure reliable execution of composite Web service and construct the optimal composite Web service. In this paper, we propose a selection approach that combines transactional properties of ensuring reliability and QoS characteristics. In the selection approach, we build automaton model to implement transactional-aware service selection and use the model to guarantee reliable execution of composite Web service. We also define aggregation functions, and use a Multiple-Attribute Decision-Making approach for the utility function to achieve Qos-based optimal service selection. Finally, two scenarios of experiments are presented to demonstrate the validity of the selection approach

An Analysis of Service Ontologies

Services are increasingly shaping the world’s economic activity. Service provision and consumption have been profiting from advances in ICT, but the decentralization and heterogeneity of the involved service entities still pose engineering challenges. One of these challenges is to achieve semantic interoperability among these autonomous entities. Semantic web technology aims at addressing this challenge on a large scale, and has matured over the last years. This is evident from the various efforts reported in the literature in which service knowledge is represented in terms of ontologies developed either in individual research projects or in standardization bodies. This paper aims at analyzing the most relevant service ontologies available today for their suitability to cope with the service semantic interoperability challenge. We take the vision of the Internet of Services (IoS) as our motivation to identify the requirements for service ontologies. We adopt a formal approach to ontology design and evaluation in our analysis. We start by defining informal competency questions derived from a motivating scenario, and we identify relevant concepts and properties in service ontologies that match the formal ontological representation of these questions. We analyze the service ontologies with our concepts and questions, so that each ontology is positioned and evaluated according to its utility. The gaps we identify as the result of our analysis provide an indication of open challenges and future work

Towards an aspect weaving BPEL engine

This position paper proposes the use of dynamic aspects and the visitor design pattern to obtain a highly configurable and extensible BPEL engine. Using these two techniques, the core of this infrastructural software can be customised to meet new requirements and add features such as debugging, execution monitoring, or changing to another Web Service selection policy. Additionally, it can easily be extended to cope with customer-specific BPEL extensions. We propose the use of dynamic aspects not only on the engine itself but also on the workflow in order to tackle the problems of Web Service hot deployment and hot fixes to long running processes. In this way, composing aWeb Service "on-the-fly" means weaving its choreography interface into the workflow

Software Reliability in Semantic Web Service Composition Applications

Web Service Composition allows the development of easily reconfigurable applications that can be quickly adapted to business changes. Due to the shift in paradigm from traditional systems, new approaches are needed in order to evaluate the reliability of web service composition applications. In this paper we present an approach based on intelligent agents for semiautomatic composition as well as methods for assessing reliability. Abstract web services, corresponding to a group of services that accomplishes a specific functionality are used as a mean of assuring better system reliability. The model can be extended with other Quality of Services – QoS attributes.Software Reliability, Web Service Composition, Intelligent Agents

People in the E-Business: New Challenges, New Solutions

[Excerpt] Human Resource Planning Society’s (HRPS) annual State of the Art/Practice (SOTA/P) study has become an integral contributor to HRPS’s mission of providing leading edge thinking to its members. Past efforts conducted in 1995, 1996, 1997, 1998, and 1999 have focused on identifying the issues on the horizon that will have a significant impact on the field of Human Resources (HR). This year, in a divergence from past practice, the SOTA/P effort aimed at developing a deeper understanding of one critical issue having a profound impact on organizations and HR, the rise of e-business. The rise of e-business has been both rapid and dramatic. One estimate puts the rate of adoption of the internet at 4,000 new users each hour (eMarketer, 1999) resulting in the expectation of 250 million people on line by the end of 2000, and 350 million by 2005 (Nua, 1999). E-commerce is expected to reach $1.3 trillion by 2003, and of that, 87 percent will go to the business to business (B2B) and 13 percent to the business to consumer (B2C) segments, respectively (Plumely, 2000)