William A. Nagy

Unraveling the Web services web: an introduction to SOAP, WSDL, and UDDI

This tutorial explores the most salient and stable specifications in each of the three major areas of the emerging Web services framework. They are the simple object access protocol, the Web Services Description Language and the Universal Description, Discovery, and Integration directory, which is a registry of Web services descriptions.

Colombo: lightweight middleware for service-oriented computing

Colombo is a lightweight platform for developing, deploying, and executing service-oriented applications. It provides optimized, native runtime support for the service-oriented-computing model, as opposed to the approach of layering service-oriented applications on a legacy runtime. This approach allows Colombo to provide high runtime performance, a small footprint, and simplified application development and deployment models. The Colombo runtime natively supports the full Web Services (WS) stack, providing transactional, reliable, and secure interactions among services. It defines a multilanguage service programming model that supports, among others, JavaTM and Business Process Execution Language for Web Services (BPEL4WS) service composition, and offers a deployment and discovery model fully based on declarative service descriptions (Web Service Description Language [WSDL] and WS-Policy). In this paper we describe these and other aspects of the architecture, design principles, and capabilities of the Colombo platform.

Implementing BPEL4WS: the architecture of a BPEL4WS implementation

BPEL4WS (BPEL in short) is a business process definition language built natively on top of the Web services application model. BPEL provides a workflow‐oriented composition model for Web services applications, and is thus a central piece in the heavily componentized service‐oriented computing model. BPEL results from the merger of two distinct process metamodels (the process algebra model of XLANG and the graph‐oriented model of WSFL) into a coherent and powerful framework. Implementing BPEL thus presents significant challenges to middleware developers. This paper discusses those challenges and describes the design and architecture of the BPWS4J runtime, and a full implementation of the BPELWS 1.1 specification. Copyright