Rania Khalaf

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.

The next step in Web services

How three specifications support creating robust service compositions.

Enterprise services

Examining the emerging field of Web Services and how it is integrated into existing enterprise infrastructures.

E Role-based Decomposition of Business Processes using BPEL

This paper addresses role-based decomposition of a business process model (based on a subset of WS-BPEL, using explicit data links. A mechanism is presented for partitioning a business process so that each partition can be enacted by a different participant. An important goal is to disconnect the partitioning itself from the design of the business process, simplifying the reassignment of activities to different entities. The result is several (compliant) BPEL processes, one for each participant, as well as the information needed to wire them together at deployment time and ensuring correct instance-level connections at runtime. We present details of partitioning and successfully running a sample process with three participants

Key challenges for enabling agile BPM with social software

Business Process Management is called agile when it is able to react quickly and adequately to internal and external events. Agile Business Process Management requires putting the life cycle of business processes on a new paradigm. It is advocated in this paper that social software allows us to satisfy the key requirements for enabling agile BPM by applying the four features of social software: weak ties, social production, egalitarianism and mutual service provision. Organizational and semantic integration and responsiveness (of the business processes engineering, execution and management activities) have been identified as the main requirements for implementing an agile BPM life cycle. Social software may be used in the BPM life cycle in several manners and using numerous approaches. This paper presents seven among them and then analyzes the ‘support’ effects between those approaches and the underlying social software features, and the three requirements for Agile BPM. Copyright

Composition of coordinated web services

The Web services architecture defines separate specifications for the composition and the coordination of Web services. BPEL is a language for creating service compositions in the form of business processes, whereas the WS-Coordination framework defines coordination protocols for distributed activities. In this paper, we investigate the combination of these two aspects to compose coordinated Web services. We argue for a policy-based approach to address this problem and introduce a new model and middleware that enables the flexible integration of diverse coordination types into (existing) process-based Web services compositions.

Composing RESTful Services and Collaborative Workflows: A Lightweight Approach

The use of RESTful Web services has gained momentum in the development of distributed applications based on traditional Web standards such as HTTP. In particular, these services can integrate easily into various applications, such as mashups. Composing RESTful services into Web-scale workflows requires a lightweight composition language thats capable of describing both the control and data flow that constitute a workflow. The authors address these issues with Bite, a lightweight and extensible composition language that enables the creation of Web-scale workflows and uses RESTful services as its main composable entities.

Business processes for web services: principles and applications

The Business Process Execution Language for Web Services (BPEL4WS or BPEL for short) is an XML-based language for defining business processes that provides an interoperable, portable language for both abstract and executable processes and that was designed from the beginning to operate in the heterogeneity and dynamism that is commonplace in information technology today. BPEL builds on the layers of flexibility provided by the Web Services stack, and especially by XML. In this paper, we provide a brief introduction to BPEL with emphasis on architectural drivers and basic concepts. Then we survey ongoing BPEL work in several application areas: adding quality of service to BPEL, extending BPEL to activities involving humans, BPEL for grid computing, and BPEL for autonomic computing.

Bite: Workflow Composition for the Web

Service composition is core to service oriented architectures. In the Web, mainstream composition is practiced in client-side or server-side mashups, such as providing visual widgets on top of Google Maps results. This paper presents an explicit, workflow based composition model for Web applications called Bite. In contrast with prior attempts to bring workflow capabilities to the Web environment, Bite can deal with data integration as well as interactive, asynchronous workflows with multi-party interactions, and is architected to support protocols currently in use by Web applications. The Bite development model is designed for simplicity and short development cycle by taking a scripting approach to workflow development.

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.