Fundamentals of SOA

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Fundamentals of SOA
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Business flexibility depends on flexible
ITSystems, processes and relationships

• IT
• Shifting focus of enterprise automation
  requirements
• Support product and service differentiation
• Support management and strategy
• Align sourcing and spend with business
  priorities

• Business
• Increasing desire for some business activities to
  change direction rapidly
• Desire for more flexible business models and
  footprints
• The freedom to innovateand involve others in
  innovation

Source MWD
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So what are we working with
IT Focus
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1990
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1960
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The Philosophy of Services Oriented Architecture
(SOA)

• SOA is about building systems out of parts.
• Parts provide some business logic.
• Parts expose application and data operations.
• Parts should be loosely coupled.

IT Business share common view of business
process.
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What is a service
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SOA Defined
Service Oriented Architecture is a paradigm for
organizing and utilizing distributed capabilities
that may be under the control of different
ownership domains. It provides a uniform means to
offer, discover, interact with and use
capabilities to produce desired effects
consistent with measurable preconditions and
expectations. OASIS SOA Reference Model
Technical Committee
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SOA Defined Part One
Service Oriented Architecture is a paradigm for
organizing and utilizing distributed capabilities
that may be under the control of different
ownership domains. It provides a uniform means to
offer, discover, interact with and use
capabilities to produce desired effects
consistent with measurable preconditions and
expectations. OASIS SOA Reference Model
Technical Committee
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Stuff we need
1. Service Enablement
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Technical Services

• Finely Grained
• Application Semantics
• Leave and Layer
• May include application processes
• Application platform providers
• Bottom up Cataloging

You already have these In your network Whether
you know it or not
Technical Services
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Business Services
Requires deliberate design

• Coarsely Grained
• Business Semantics
• Enables Business Processes
• Top Down Decomposition

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Business Services
Technical Services
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SOA Defined Part Two
Service Oriented Architecture is a paradigm for
organizing and utilizing distributed capabilities
that may be under the control of different
ownership domains. It provides a uniform means to
offer, discover, interact with and use
capabilities to produce desired effects
consistent with measurable preconditions and
expectations. OASIS SOA Reference Model
Technical Committee
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SOA Defined Part Three
Service Oriented Architecture is a paradigm for
organizing and utilizing distributed capabilities
that may be under the control of different
ownership domains. It provides a uniform means to
offer, discover, interact with and use
capabilities to produce desired effects
consistent with measurable preconditions and
expectations. OASIS SOA Reference Model
Technical Committee
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Stuff we need
1. Service Enablement
2. Service Access/Interaction
3. Service Registry
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Finding and Using Services
"SOA is a mess waiting to happen. By encouraging
widespread reuse of scattered software
components, SOA threatens to transform the
enterprise network into a complex, sprawling,
unmanageable mesh. Left ungoverned, SOA could
allow anyone anywhere to deploy a new service any
time they wish, and anyone anywhere to invoke and
orchestrate that service--and thousands of
othersinto ever more convoluted messaging
patterns." James Kobielus, principal analyst at
Current Analysis
SOA could allow anyone anywhere to deploy a new
service any time they wish, and anyone anywhere
to invoke and orchestrate that service
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Interdependence Can Destroy Agility
How can you change anything once everything is
tied together?
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The Dangers of Service Spaghetti
"SOA is a mess waiting to happen. By encouraging
widespread reuse of scattered software
components, SOA threatens to transform the
enterprise network into a complex, sprawling,
unmanageable mesh. Left ungoverned, SOA could
allow anyone anywhere to deploy a new service any
time they wish, and anyone anywhere to invoke and
orchestrate that service--and thousands of
othersinto ever more convoluted messaging
patterns." James Kobielus, principal analyst at
Current Analysis
complex, sprawling, unmanageable
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Why all this complexity ?
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Governance is key for SOA
lack of working governance mechanisms in
midsize-to-large (greater than 50 services)
post-pilot SOA projects will be the most common
reason for project failure Jess Thompson,
Research Director, Gartner
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Stuff we need
1. Service Enablement
2. Service Access/Interaction
3. Service Registry
4. SOA Governance
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Key applications