Professional WCF 4: Windows Communication Foundation with .NET 4

Chapter 1. Design Principles and Patterns

WHAT'S IN THIS CHAPTER?

• Exploring services and SOA

• Understanding communication and integration patterns

• Working with business process patterns

This chapter describes a number of principles and patterns regarding Service Orientation, Integration, and Business Processes. You will see how these principles are related to WCF and how you can use WCF to implement the patterns.

WHAT IS SOA?

SOA or service-oriented architecture is a style of programming, an architectural approach in software development, where an application is organized in functional units of code with a given behavior called services.

Services are a group of methods that share a common set of requirements and functional goals. They are called by other parts that need to execute its logic, depending on the outcome (such as data, results of calculations, and so on). The functions have a clearly defined and public signature which is published so other code (service clients) can use the functions in the service as a black box. The service operations are invisible — there is no direct interaction with a user and the work is executed as instructed by the given input parameters. SOA allows distributed applications to be organized. This means that the service consumers are running on different machines than the services. This allows the business logic and run user interfaces to be centralized or other consumers to be decentralized across the network. To make this happen in SOA, structured messages ...