SOA: the basics

1
SOA the basics

• What it is.
• What it is not.

2
SOA the false, the ideal, the real

• False SOA equals web services.
• SOA equals distributed services.
• Ideal SOA cleanly partitions and consistently
  represent business services.
• Real SOA is a fundamental change in the way we
  do business.

3
Real SOA

• Changed mindset service-oriented context for
  business logic.
• Changed automation logic service-oriented
  applications.
• Changed infrastructure service-oriented
  technologies.
• A top-down organization transformation requiring
  real commitment.

4
SOA Characteristics

• Loosely coupled minimizes dependencies between
  services.
• Contractual adhere to agreement on service
  descriptions.
• Autonomous control the business logic they
  encapsulate.
• Abstract hide the business logic from the
  service consumers.

5
SOA Characteristics

• Reusable divide business logic into reusable
  services.
• Composable facilitate the assembly of composite
  services.
• Stateless minimize retained information specific
  to an activity.
• Discoverable self-described so that they can be
  found and assessed.

6
Potential Benefits

• Based on open standards.
• Supports vendor diversity.
• Fosters intrinsic interoperability.
• Promotes discovery.
• Promotes federation.
• Fosters inherent reusability.
• Emphasizes extensibility.

7
Potential Benefits

• Promotes organizational agility.
• Supports incremental implementation.
• Technical architecture that adheres to and
  supports the principles of service orientation.

8
Common Misperceptions

• SOA is just Web services.
• SOA is just a marketing term.
• SOA is just distributed computing.
• SOA is a magic global solution to general
  interoperability.

9
Focus on the Business Process and Services
Application a
Application c
Application b
Application logic
Source Service-Oriented Architecture, Thomas Erl
10
Focus on the Business Process and Services
Business process layer
Business-oriented services
Services interface layer
Application-oriented services
Application layer
.NET
J2EE
Legacy
Source Service-Oriented Architecture, Thomas Erl
11
Focus on the Business Process and Services
Business process layer
Services interface layer
Application layer
.NET
J2EE
Legacy
Source Service-Oriented Architecture, Thomas Erl
12
Common Pitfalls

• Not basing SOA on standards.
• Not creating a transition plan.
• Not starting with a solid XML foundation
  architecture and skill set.
• Not understanding SOA performance requirements.
• Not understanding web services security.

13
Summing Up SOA

• Not a magic trick.
• Not a magic solution.
• Not an easy thing to do correctly.
• The wavelet of the present.
• The wave of the future.
• A useful architectural concept.
• A potential business facilitator.

14
Resources

• Douglas K. Barry, Web Services and
  Service-Oriented Architectures the savvy
  managers guide.
• Thomas Erl, Service-Oriented Architecture
  concepts, technology and design.
• Thomas Erl, Service-Oriented Architecture a
  field guide to integrating XML and web services.