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Fundamental Design
Terminology and Concepts
    Introduction
    Design Characteristic
    Design Principle
    Design Paradigm
    Design Pattern
    Design Pattern Language
    Design Standard
    Best Practice

Elements of
Service-Oriented Computing
    Introduction
    Service-Oriented
Architecture (SOA)
    Services and
Service-Orientation
    Service Compositions
    Service Inventory
    A Conceptual View of
Service-Oriented Computing
    A Physical View of
Service-Oriented Computing

Goals and Benefits of
Service-Oriented Computing
    Introduction
    Increased Intrinsic Interoperability
    Increased Federation
    Increased Vendor Diversification Options
    Increased Business and Technology Domain Alignment
    Increased ROI
    Increased
Organizational Agility
    Reduced IT Burden

Service-Oriented Computing
in the Real World
    Services as Web Services
    About Web Services (Part I)
    About Web Services (Part II)
    Service Models and
Service Layers
    Service Inventory Blueprints
    Service-Oriented Analysis
    Service-Oriented Design

Additional Resources
    SOA Sites
    SOA Book Series
    SOA Training & Certification
    Free SOA Principles Poster
    Notification


Service-Oriented Computing in the Real World

Service-Oriented Design

The service-oriented design process uses a set of predefined service candidates from the service inventory blueprint as a starting point from which they are shaped into actual physical service contracts.

When carrying out service-oriented design, a clear distinction is made between service candidates and services. The former represents a conceptual service that has not been implemented, whereas the latter refers to a physical service.

As shown in the following figure, the traditional (non-standardized) means by which Web service contracts are generated results in services that continue to express the proprietary nature of what they encapsulate. Creating the Web service contract prior to development allows for standards to be applied so that the federated endpoints established by Web services are consistent and aligned.


Figure: Unlike the popular process of deriving Web service contracts from existing components, SOA advocates a specific approach that encourages us to postpone development until after a custom designed, standardized contract is in place.

This "contract first" approach lies at the heart of service-oriented design and has inspired separate design processes for services based on different service models. For more information, visit www.SOAMethodology.com.

This page contains excerpts from:

SOA: Principles of Service Design
by Thomas Erl

ISBN: 0132344823, Prentice Hall/PearsonPTR, Hardcover
240+ Full Color Illustrations, 573 pages

Download the free Color SOA Principles Poster at www.soaposters.com.
For more information about this book, visit
www.soabooks.com.
The Prentice Hall Service-Oriented Computing Series from Thomas Erl
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