The orchestration service layer provides a powerful means by which contemporary service-oriented solutions can realize some key benefits. The most significant contribution this sub-layer brings to SOA is an abstraction of logic and responsibility that alleviates underlying services from a number of design constraints.
For example, by abstracting business process logic:
In this chapter we tackle the design of an orchestration layer by using the WS-BPEL language to create a business process definition.
How case studies are used: Our focus in this chapter is the TLS environment. We provide case study examples throughout the step-by-step process description during which TLS builds a WS-BPEL process definition for the Timesheet Submission Process. This is the same process for which service candidates were modeled in Chapter 12 and for which the Employee Service interface was designed in Chapter 15.
Part I: SOA and Web Services Fundamentals
The Evolution of SOA
Web Services and Primitive SOA
Part II: SOA and WS-* Extensions
Web Services and Contemporary SOA (Part I: Activity Management and Composition)
Web Services and Contemporary SOA (Part II: Advanced Messaging, Metadata, and Security)
Part III: SOA and Service-Orientation
Principles of Service-Orientation
Part IV: Building SOA (Planning and Analysis)
SOA Delivery Strategies
Service-Oriented Analysis (Part I: Introduction)
Service-Oriented Analysis (Part II: Service Modeling)
Part V: Building SOA (Technology and Design)
Service-Oriented Design (Part I: Introduction)
Service-Oriented Design (Part II: SOA Composition Guidelines)
Service-Oriented Design (Part III: Service Design)
Service-Oriented Design (Part IV: Business Process Design)
Fundamental WS-* Extensions
Appendix A. Case Studies: Conclusion