UPGRADE: Vol. VII, Issue no. 5, October 2006 (Web Services)

Web Services

Published on behalf of CEPIS by Novática (ATI, Spain)

Chief Editor: Llorenç Pagés-Casas, <pages AT ati DOT es>

Associate Editors:

François Louis Nicolet, <nicolet AT acm DOT org>; Roberto Carniel, <rcarniel AT dgt DOT uniud DOT it>; Zakaria Maamar, <Zakaria DOT Maamar AT zu DOT ac DOT ae>; Soraya Kouadri Mostéfaoui, <soraya DOT kouadrimostefaoui AT unifr DOT ch>, Rafael Fernández Calvo, <rfcalvo AT ati DOT es>.

Abstract: The World Wide Web Consortium (W3C) is a vendor-neutral forum founded in 1994 to develop Web standards and design technologies to ensure that the Web will continue to thrive in the future. This article gives a broad outline of the W3C’s organization and its main goals, and a brief explanation of the long process of standardization, in which anyone interested can be involved. W3C is focused on core standards for the Web and establishes liaisons with other organizations developing complementary technologies. In the dynamic area of Web Services, we can see that there is active collaboration between organizations and the public. W3C’s activity is growing at a rapid rate because Industry has a great deal of interest in solving its technological problems with these interoperability mechanisms. The need for standardization arises when different parties are researching similar topics.

Abstract: The Technological environment in Healthcare has usually been defined as a group of information islands. Systems involved have a high degree of specialization in those areas which they support but, in general, they are not oriented to integration and interoperability. In this scenario Business Oriented Applications seem to be a possible solution. Unfortunately, and even when it is commonly accepted that such systems have solved a part of an existing problem, there are a number of reasons which make it impossible to accept them as the best solution. One of those reasons is they unavoidably reside within departmental applications such as Digital Imaging, Pharmacy or Laboratory. Lately, a new approach, which takes advantage of the last technological advance, Service Oriented Architecture and Integration standards in the Healthcare sector, has arisen.

Abstract: Currently one of the most promising technologies, Web Services are at the intersection of distributed computing and loosely coupled systems. Although vendors provide multiple platforms for service implementation, service integrators, developers and providers demand approaches for managing service-oriented applications at all stages of development. In this sense, we propose a cross-disciplinary approach in which Model-Driven Development (MDD), Service Component Architecture (SCA) and WS-Policy are assembled in order to integrate extra-functional properties in web service models and manage them from the client side. The initial platform-independent model is later transformed into a platform-specific model from which final code is automatically generated.

Abstract: Many software companies are using SOA (Service-oriented Architectures) as the cornerstone of their business activities. In this context, automated service provision based on the creation of service agreements is gaining importance in both cross-organizational and intra-organizational scenarios because they provide important benefits to both the service consumer and the service provider. On the one hand, service agreements provide consumers with guarantees about how a service will be provided. On the other hand, service agreements allow the providers to deploy automated service provision based on the agreements they have made with their customers. Service agreements are a prominent research field in both academia and industry. In this article, we focus on the service trading process, which is the process of locating, selecting, negotiating, and creating service agreements. This process can be applied to a variety of scenarios and therefore their requirements are also very different.

Abstract: The integration of applications is one of the main challenges when building IT solutions. Integration is often achieved using costly customized solutions for every pair of applications. Web service technologies are a set of standards that allow software interfaces to be defined using XML (eXtensible Markup Language) as the message format and the Internet infrastructure for message transport. While lowering costs, Web service technologies by themselves do not ensure that two businesses use the same data structures or business protocols, neither do they provide the means to resolve potential conflicts. The lack of formal descriptions of services offered by organizations hampers automation in the location and usage of services required to perform a given business activity. Semantic Web Services enable the formal specification of services, allowing their automated, goal-driven location and usage. The Web Service Modelling Ontology (WSMO) provides a framework for the description of Semantic Web services which enables seamless integration through formal descriptions, maximal decoupling of components, and strong mediation support.

Abstract: There are various B2B scenarios where many candidate services with the same or similar capability (provided by the same or even different service providers) can be used for integration. Hence, a requester driving a B2B integration scenario can choose among several candidate services offering a capability of satisfying the request. However, the optimal choice of the service to be invoked often depends on the parameters of the request at run-time and the preferences of the requester. In this article we describe a solution for a dynamic (at run-time) web service selection based on semantic interpretation of offered service capabilities and the parameters specifying the run-time request. The proposed solution takes into account special conditions on service usage either contractually agreed between requester and provider or specified by the requester without the knowledge of the provider. In general, these conditions restrict the interpretation of the original service capabilities as offered by a service provider and influence the choice of a service.

Leveraging E-Marketplaces Models for Web Service-Based Application Development [PDF: 6 pages, 191 KB]
Abraham Nieva de la Hidalga, Liping Zhao and Pedro R. Falcone-Sampaio

Abstract: There is a growing interest in using and developing Web Service based systems. However, current Web Service applications have been developed as highly customised and tightly coupled systems due to their architectural model and are therefore difficult to maintain and adapt. This paper proposes a new architectural model based on the concept of e-marketplace to support the design, development, reuse, and publication of loosely coupled Web Services. A survey is used to highlight the importance of e-marketplaces. An agent based model is adapted to support the basic definition of the architecture. A proposal for an architectural model for Web Services based on the e-marketplace concept is presented as a preliminary step to extend the e-marketplace model into a platform to support the development, publishing and discovery of Web Services.

Jose Carlos del Arco-Prieto is a graduate in Computer Science from the Universidad de Huelva (1998). Later his professional career began in Tecsidel (1999) where he participated in projects for Telefónica I+D and made analyses of the impact of Web Services on different markets (2002). In 2004 he worked in the Diputacion de Huelva (Huelva Provincial Council) participating in the European project “Regions on Line” (ROL). In 2005 he worked in Cibernos collaborating on the Diraya project led by Indra and participating in the development of proposals of interoperability models and Web Services-based integration. He is currently working for T-Systems, doing technical consultancy work and collaborating in the definition of interoperability models, integration for the public sector, and the design of methodologies for SOA development. He collaborates with the Universidad de Huelva in the promotion of Web 2.0 technologies. He is the father of the first Web Services Latin list (webservices-Latinos), promoter of JSWEB 2005 Workshop, Co-president of JSWEB 2006 Workshop and a member of the steering committee of European SOA & Application Architecture Conference (2007). One of his main interests is the convergence between the worlds of academia and business. <josecarlos DOT delarco AT t-systems DOT es>.

Jesús Arias-Fisteus works as an assistant professor in the Telematic Engineering Department of the Universidad Carlos III de Madrid. He received his MSc with honours in Telecommunication Engineering in 2001 from the Universidad de Vigo. In 2005, he received his PhD in Communication Technologies from the Universidad Carlos III de Madrid. His research topics include the application of formal methods, especially model checking, to the verification of business processes and Web Service compositions. Recently, he has also become interested in the Semantic Web and Semantic Web Services. He has worked on several European and Spanish research projects related to the field of Web Services. He has also authored more than 15 papers in national and international journals and workshops / conferences in related fields. He was a temporary research visitor at the IT Innovation Centre at Intel Ireland in 2004, and a visiting scientist under the direction of Prof. Tim Berners-Lee at the Decentralized Information Group of the Massachusetts Institute of Technology in 2006. <jaf AT it DOT uc3m DOT es>.

Oscar Corcho-García works as a Marie Curie fellow at the University of Manchester. Previously, he has worked at iSOCO as a research manager and at the Ontological Engineering Group of the Universidad Politécnica de Madrid (UPM). He graduated with honours in Computer Science from UPM in 2000, obtained his MSc in Software Engineering from UPM in 2001, and his PhD in Artificial Intelligence in 2004. He received the third Spanish award in Computer Science from the Spanish Government (2001) and a PhD thesis award from the Universidad Politécnica de Madrid (2005). His research activities include the Semantic Grid, the Semantic Web, and ontology engineering. He has participated in several leading EU projects in these areas: OntoGrid, Esperonto, DIP, HOPS, SWWS, Knowledge Web, OntoWeb, and MKBEEM. He has also taken part in the HALO project, funded by Vulcan, Inc. He has published the books "Ontological Engineering" and "A layered declarative approach to ontology translation with knowledge preservation", over 30 journal and conference/workshop papers, and he reviews papers in several conferences, workshops and journals. He has also been a research visitor at KMI (Open University) and SMI (Stanford University). He chaired the demo/industrial sessions at EKAW2002, co-organized the ISWC2003 and ISWC2004 Workshops on Evaluation of Ontology Tools (EON2003, EON2004) and was the sponsor chair of the ESWC2006 conference. <oscar DOT corcho AT manchester DOT ac DOT uk>.

Jorge Cardoso joined the Universidade de Madeira in March 2003. He previously lectured at the University of Georgia (USA) and the Instituto Politécnico de Leiria (Portugal). While at the University of Georgia he formed part of the LSDIS Lab where he performed extensive research on Workflow Management Systems. His current interests include Workflow Quality of Service, Semantic Workflow Composition, Web Services, Web Processes, e-Commerce, and Groupware/CSCW. <jcardoso AT uma DOT pt>.

UPENET (UPGRADE European NETwork) [PDF: 18 pages, 475 KB]

From Novatica (ATI, Spain)
Open Standards
Open Standards, A Renewed Impulse: The Case of Open Document Format
Miguel A. Amutio-Gómez

This paper was first published, in Spanish, by Novática (issue no. 181, May-June 2006, pp. 69-73). Novatica, a founding member of UPENET, is a bimonthly journal published in Spanish by the Spanish CEPIS society ATI (Asociación de Técnicos de Informática – Association of Computer Professionals).

Abstract: Open Document Format is an XML-based (eXtensible Markup Laguage) file format for documents on electronic media. It has recently been adopted as the standard ISO/IEC 26300 (International Organization for Standardization/International Electrotechnical Commission) and has been an OASIS (Organization for the Advancement of Structured Information Standards) standard since May 2005. OpenDocument file format arouses great interest because it is non-binary, multiplatform, and can be implemented by various tools; because its specification is public, open, neutral and royalty free; and because of the impact that such characteristics have on freedom of choice, interoperability, and preservation of information. This article provides an overview of OpenDocument: what it is, who is responsible for it and who maintains it, what it is like inside, which applications support it, and why it arouses such interest. It also describes the project carried out as part of the European IDA/IDABC (Interchange of Data between Administration/(Interoperable Delivery of Pan-European eGovernment Services to Public Administrations, Business and Citizens) programme for the promotion of open formats for document exchange, in the context of public policies in the field of open standards.

From Mondo Digitale (AICA, Italy)
ICT Security
Critical Information Infrastructure Protection
Sandro Bologna, Roberto Setola and Salvatore Tucci

This paper was first published, in its original Italian version, under the title “Le infrastrutture critiche informatizzate”, by Mondo Digitale (issue no. 16, December 2005, pp. 20-31). Mondo Digitale, a founding member of UPENET, is the digital journal of the CEPIS Italian society AICA (Associazione Italiana per l'Informatica ed il Calcolo Automatico).

Abstract: The global shift in the socio-economic paradigm calls for the adoption of new policies to ensure the security of the infrastructures that use ICT (Information and Communication Technologies) technologies to distribute essential services for the wellbeing of populations (Protection of Critical Information Infrastructures). The correct definition of such instruments cannot ignore the existence of interdependencies between the various infrastructures. This is a new phenomenon, one which is complex and strongly interdisciplinary, requiring the development of new methodologies and tools for the analysis of systems comprising a number of heterogeneous and interdependent infrastructures.

From ITNOW (BCS, United Kingdom)
Informatics Profession
Professionalizing IT
Peter Skyte

This paper was first published by ITNOW (Volume 48, issue # 5, September 2006, pp. 32-33). ITNOW, a UPENET partner, is the bimonthly magazine for BCS members published, in English, by Oxford University Press on behalf of the British CEPIS society BCS (British Computer Society). To access the full September 2006 issue of ITNOW click here.

Abstract: It's taken for granted that occupations generally understood to be professionals, such as teachers, doctors, nurses, architects, lawyers, accountants and others are regulated either by professional bodies (RIBA, ACA and others) or independent regulatory organizations (General Teaching Council, GMC, NMC). However it is easy to forget that this was not always the case, and such professionalism has in many cases had a long history of development, often arising from public scandal at the time and the resultant public outcry for 'something to be done'. Now it's the turn of IT.

CEPIS NEWS [PDF: 1 page, 60 KB] **NEW SECTION**

Harmonise Project: Presentation.
The aim of this project is contributing to establish comparable data on ICT vocational training systems and various approaches to ICT qualification and ICT certification in the participating countries.

Monograph: Web Services

Presentation
Web Services from An Industrial and An Academic Perspective [PDF: 3 pages, 92 KB]
(includes a set of useful references about the matter)
José Carlos del Arco-Prieto, Jesús Arias-Fisteus, Oscar Corcho-García and Jorge Cardoso - Guest Editors

Web Services have gained great importance in academic and industrial environments due to their focus on open standards widely accepted by industry, which guarantee interoperability between the information systems of different organizations.

The emergence of Web Services has had a major impact on the way in which organizations integrate their applications, data, and processes. The use of standards has reduced the cost of corporate integration projects by allowing the reuse of existing applications and benefiting from previous investments. Web Service adoption in the industry has allowed organizations to share information with their partners, providers, and customers in a standardized manner.

In academia, the number of papers, conferences, projects, and research lines focusing on Web Services related aspects has grown in the last years. Research is focused on the implications of applying Web Services to areas such as B2B, EAI, BPM, EC, Grid Computing, and Semantic Web. Web Services have been crucial to the emergence of such paradigms as Service Oriented Architectures (SOAs).

This special issue contains a number of papers related to the industry and academic world describing the state of the art of Web Services, fundamental approaches and frameworks, work in progress, and the impact of this technology on different types of applications.

The issue kicks off with the paper “Web Services: Introduction and State of The Art”, prepared by the issue’s editors with the aim of introducing the world of Web Services. This paper presents a general overview of the implications of Web Services in different industrial and academic areas.

The World Wide Web Consortium (W3C) is the most important standardization consortium in the field of Web technologies. It has developed and standardized a number of key Web technologies such as XML and the latest versions of HTML. The paper “W3C and Web Services Standardization”, authored by Martín Álvarez-Espinar from the W3C Spanish Office, explains the mission of the W3C and its important role in the standardization of Web service technologies.

The paper “Integration and Interoperability Experiences in Healthcare”, by Antonio García-Landeira, gives an example of how Web Services are applied in the Health sector to integrated Hospital Information Systems. This integration effort follows the basic principles of Service Oriented Architectures (SOAs) and Enterprise Service Buses (ESBs).

The paper “Model-Driven Extra-Functional Property Development for Web Services: a Case Study from The Service and Client Side Perspectives”, by Guadalupe Ortiz-Bellot and Juan Hernández-Núñez, proposes a multi-disciplinary approach that uses Model Driven Development (MDD), Services Component Architecture (SCA) and WS-Policy to integrate non-functional properties in service models, and the administration of such properties by service clients.

The paper “Semantic Web Services with WSMO”, from Holger Lausen, Jos de Bruijn, Uwe Keller and Rubén Lara deals with the role of Semantic Web Services in the formal specification of services, allowing the automation of their localization and use. WSMO provides an infrastructure for the description of Semantic Web Services enabling the specification of services, and supports mediation in order to overcome interoperability problems.

On the subject of Service Level Agreements and Contracts we would highlight the paper “Towards An Automated Trading Process”, by Pablo Fernandez-Montes, Manuel Resinas-Arias de Reyna and Rafael Corchuelo-Gil, which focuses on the automatic provision of services based on Service Level Agreements between provider and clients, and describes the activities involved in the service negotiation process and its application in different scenarios.

Service selection is a hot topic in Semantic Web Services. The paper “Towards Semantic Service Selection for B2B Integration”, by Andreas Friesen and Kioumars Namiri describes a solution for the dynamic selection of Web services based on the semantic interpretation of the capabilities of the services offered and of the parameters specified at run-time.

The paper “Leveraging E-Marketplace Models for Web Service-Based Application Development”, by Abraham Nieva de la Hidalga, Liping Zhao and Pedro R. Falcone-Sampaio proposes the application of the current e-marketplace model to the development of Web Service-based applications.

We would like to thank the authors for contributing their papers and the editors of Novática and UPGRADE for their help during the edition of this special issue. We hope that this issue will be also helpful for readers of Novática and UPGRADE.

Below we provide some relevant references about the world of Web Services for those readers who wish to go into this area in greater depth.

Useful References on Web Services

The following references, along with those included in the articles this monograph consists of, will help our readers to dig deeper into this field.

Books

E. Newcomer, G. Lomow. Understanding SOA with Web Services, Addison-Wesley, 2005. ISBN: 0-321-18086-0.
S. Weerawarana, F. Curbera, F. Leymann, T. Storey, D. Ferguson. Web Services Platform Architecture, Prentice Hall, 2005. ISBN: 0-131-48874-0.
G. Alonso, F. Casati, H. Kuno, V. Machiraju. Web Services. Concepts, Architectures and Applications, Springer, 2004. ISBN: 3-540-44008-9.
Douglas Barry. Web Services and Service-Oriented Architectures. The Savvy Manager’s Guide, Morgan Kaufmann, 2003.
Doug Kaye. Loosely Coupled. The Missing Pieces of Web Services, Kaye, 2003. ISBN: 1-881-37824-1.
“Actas JSWEB’2005”. Editores: E. Marcos, J. Alonso, V. de Castro, J. del Arco. Thompson, 2005.

Magazines and Journals

SOA Web Services Journal: <http://webservices.sys-con.com/>.

Business Integration Journal: <http://www.bijonline.com/>.

International Journal of Web Services Research: <http://www.idea-group.com/journals/details.asp?id=4138>, <http://www.servicescomputing.org/jwsr/>.

International Journal of Web and Grid Services: <https://www.inderscience.com/browse/index.php?journalID=47>.

SOA Magazine: <http://www.soamag.com/>.

Conferences

ICWS 2005: <http://conferences.computer.org/icws/2005/>.

ICWS 2006: <http://conferences.computer.org/icws/2006/>.

JSWEB 2005: <http://www.w3c.es/Eventos/ServiciosWeb/>.

JSWEB 2006: <http://www-gsi.dec.usc.es/jsweb06/>.

ECOWS 2006: <http://www.ifi.unizh.ch/ecows06/>.

Web Sites

W3C: <http://www.w3.org/>.

OASIS: <http://www.oasis-open.org/>.

WS-I: <http://www.ws-i.org/>.

Webservices.org: <http://www.webservices.org>.

SearchWebservices.com: <http://www.searchwebservices.com>.

Discussion lists

Service-orientated-architecture: <http://groups.yahoo.com/group/service-orientated-architecture/>.

www-ws@w3.org: <http://lists.w3.org/Archives/Public/www-ws/>.

public-sws-ig@w3.org: <http://lists.w3.org/Archives/Public/public-sws-ig/>.

webservices-latinos: <http://es.groups.yahoo.com/group/webservices-latinos/>.

soapbuilders: <http://groups.yahoo.com/group/soapbuilders/>.

rest-discuss: <http://groups.yahoo.com/group/rest-discuss/>.

Glossary of terms

ACM - Association for Computing Machinery
AOP - Aspect Oriented Programming
API - Application Programming Interface
ASP - Application Service Provider
B2B - Business to Business
B2Bi - Business to Business Integration
BPI - Business Process Integration
BPM - Business Process Management
BPMI - Business Process Management Initiative
BPO - Business Process Outsourcing
CORBA - Common Object Request Broker Architecture
CRM - Customer Relationship Management
DCOM - Distributed Component Object Model
EAI - Enterprise Application Integration
EDI - Electronic Data Interchange
ERP - Enterprise Resource Planning
ESB - Enterprise Services Bus
ebXML - Electronic Business XML Initiative
HTTP - Hypertext Transport Protocol
IEEE - Institute of Electrical and Electronics Engineers
JMS - Java Message Service
JSR - Java Specification Requests
J2EE - Java 2 Platform Enterprise Edition
J2ME - Java 2 Platform, Micro Edition
J2SE - Java 2 Platform, Standard Edition
MDA - Model Driven Architecture
MOM - Messaging Oriented Middleware
OGSA - Open Grid Services Architecture
OGSI - Open Grid Service Infrastructure
OMG - Object Management Group
OASIS - Organization for the Advanced Structured Information Standards
QoS - Quality of Service
RPC - Remote Procedure Call
SCM - Supply Chain Management
SLA - Service Level Agreement
SOA - Services-Oriented Architecture
SOAP - Simple Object Access Protocol
UDDI - Universal Description, Discovery and Integration
URL - Universal Resource Locator
VAN - Virtual Area Network
W3C - World Wide Web Consortium
WS-BPEL - Business Process Execution Language
WSDL - Web Services Description Language
WSRF - Web Services Resource Framework
WSRP - Web Services for Remote Portlets
XML - Extensible Markup Language

Last updated on December 27th, 2006

by the Editorial Team of Upgrade