of business processes that cross the boundaries of an organization into new business solutions and ultimately e-business. Yet, Web services deployment is still ...
Approaches to Identify and Develop Web Services as Instance of SOA Architecture Najla AI-Rawahi', Youcef Baghdad?
'* Department of Computer Science, PO Box 34-PC 123 AI-Khoud, Oman ',* (m000133, ybaghdadi) @squ.edu.om deployment, and management. The paper presents a comparative study of two perspectives of developing Web services: IT-oriented and business-oriented perspectives with respect to: (1) the development process being it implicit or explicit, i.e. top-down, bottom-up, incremental, or mixed, (2) the main building blocks used to identify Web services, i.e. business organization into new business solutions and ultimately object (data-centric approach), business function e-business. (function-centric), business process, component, or object Yet, Web services deployment is still hindered by technical (class), (3) the legacy applications, i.e. the wrapping process, and especially methodological issues. This paper concerns with (4) the categories, i.e. internal/extemal, findcoarse-grained, approaches to develop Web services, namely their identification, query/transactional, utility services. design, deployment, and management IT-oriented approaches are purely depending upon the The paper presents a comparative study of two perspectives of developing Web services: IT-oriented and business-oriented technologies such as Microsoft's .NET, Sun's platform perspectives with respect to: (1) developing process, (2) used including J2EE, IBM's Websphere, Oracle's technology, or building blocks, (3) categories of Web services, and (4) TME's Glue, which generally consist of (i) generating Web wrapping of legacy applications. services interfaces from existing classes, components or This comparative study aims at integrating both perspectives stored procedures, or using adapters to wrap existing legacy into a multiple abstraction level architecture with respect to a business model, where higher abstract levels deal with applications, and (ii) generating stubs (proxies), which are used by the client application to invoke the Web services. businessorientation, whereas the lower levels concern with IT. Business-oriented approaches consist generally of Keywords: Web services; Architecture; Methodology; IT-oriented approaches; Business-oriented approaches; abstracting the Web services with respect to business model Comparison study andor enterprise architecture. The main conclusion of this comparative study highlights I. INTRODUCTION the necessity to integrate both perspectives into a multiple Currently Web services are becoming a simple abstraction level architecture with respect to a business model, service-oriented architecture (SOA) with lower development where higher abstract levels deal with business-orientation costs [l]. The underlying standards and technologies allow and are technology-independent, whereas, the lower levels interfacing, publishing, and binding loosely coupled services concern with IT. The architecture will be then used as available on the Web. Web services can: (i) easily live with guidance towards a comprehensive design process of a Web distributed object-computing middleware such as CORBA, services based service oriented architecture (SOA). The remainder of the paper is organized as follows. The DCOM and EJB [2], (ii) make legacy databases and applications, and even traditional EM messaging look like next
