Service Oriented Architecture (SOA) Dennis Schwarz November 21, 2008

Business Drivers for SOA SOA can be seen as the result of pressure on organizations to become more efficient and agile Traditional IT systems are characterized by Monolithic applications with the technology, processes, business rules, logic and data tightly coupled Applications support specific business functions Applications are difficult to customize and are inflexible to changes in the business structure As the business environment changes, the applications often do not support changes to the enterprise’s strategy to improve competitiveness

Integrating Business Applications Business Environment Businesses are typically composed of many departments, which frequently operate as silos, performing functional activities Applications developed and funded to support an organization often provide little utility other than to the department users These departments need to collaborate to accomplish the end-to-end business processes and achieve the business goals Process improvement within companies often means better collaboration and integration between departments

Traditional IT Infrastructure Constrains Business Agility and Growth Business Processes IT Applications Efficiency Business Growth Application Customization & Integration Constraints: Tightly Coupled technology, processes, business rules, logic and data R1 B1 Delay S O S S S S S – Strengthens Change O – Opposing Change R1 – Reinforcing Loop B1 – Balancing Loop R B IT Reinforces Growth IT Constrains Growth Business Growth IT Infrastructure

Emergence of SOA Survey found that 68% to 88% of current SOA implementations are used for integration of applications As distributed systems technologies evolved, SOA emerged as the architecture that leverages these advancements and lessons learned to capture the business design and implement it in the information systems As distributed systems technologies evolved, SOA emerged as the architecture that leverages these advancements and lessons learned to capture the business design and implement it in the information systems

Addressing IT Complexity SOA approach Smaller projects are implemented to create loosely coupled services to address immediate needs These services then function as reusable building blocks for future projects The larger the compilation of services in an enterprise’s inventory, the greater the resources that can be orchestrated to address changes the business desires SOAs help reduce complexity through decoupling technology providing granular services which hide details providing reuse of existing components service contracts which document the components and usage decomposition of systems into application front-ends and services

SOA Enables Agility and Sustainable Growth Business Processes IT Applications Efficiency Business Growth Application Customization & Integration Services Repository Loosely Coupled, technology independent, Reusable building blocks R1 R2 S S S S S S S – Strengthens Change R1 – Reinforcing Loop R2 – Reinforcing Loop R IT Reinforces Growth Business Growth IT Infrastructure

What is an SOA? SOA is an information system architectural style, which implements business processes as a composition of services and policies which govern their use A service can be viewed as a task within a business process The business process is then treated as a composition of services in the IT architecture SOA provides an information technology (IT) architecture that closely aligns with and supports the business process architecture SOA provides a flexible IT structure that can rapidly accommodate new or changes to business processes

Definition “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,2006) “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,2006)

SOA Approach to Collaboration Service Consumer Service Registry Service Provider Bind and Invoke Find Publish Service Description Service Description

Elements of SOA * Graphic by Dirk Krafzig, Karl Banke, and Dirk Slama. Enterprise SOA. Prentice Hall, 2005

SOA Represented as a Layered Architecture Business Process Choreography Services Enterprise Components Operational Systems Presentation Enterprise Service Bus Governance – QoS, Management and Monitoring

SOA Interface Diagram

Adoption by Industry 2007 study showed that SOA penetration was at 62%, which was an increase of 17% from % of companies surveyed that had more than 20,000 employees either had or would adopt SOA within a year Companies with an enterprise commitment and strategy were 36% more likely to increase there SOA deployments versus companies that pursued a selective approach Only 3% of those surveyed responded that they would do less with their SOA deployment

SOA Adoption By Government The DoD like the commercial enterprises describe above historically acquired and managed IT capabilities as stand alone systems. System-to-system connections were implemented as point-to-point solutions with a focus on system rather than mission capabilities. This approach yielded a network consisting of information silos that cannot communicate with each other unless pre-wired to do so. It produced overlapping capabilities and limited ability to share information. Tying stovepipes together one pair at a time resulted in a fragile environment that will not address the demands and unpredictable needs of users. In addition, the network of silo information systems will not scale to support the levels of interaction for a networked force. (Grimmes, 2007) The DoD like the commercial enterprises describe above historically acquired and managed IT capabilities as stand alone systems. System-to-system connections were implemented as point-to-point solutions with a focus on system rather than mission capabilities. This approach yielded a network consisting of information silos that cannot communicate with each other unless pre-wired to do so. It produced overlapping capabilities and limited ability to share information. Tying stovepipes together one pair at a time resulted in a fragile environment that will not address the demands and unpredictable needs of users. In addition, the network of silo information systems will not scale to support the levels of interaction for a networked force. (Grimmes, 2007)

Important Resources IBM SOA Website Check the IBM library of papers on SOA Reference Model for Service Oriented Architecture, OASIS open.org/committees/tc_home.php?wg_abbrev=soa-rm SMART: The Service-Oriented Migration And Reuse Technique - Carnegie Mellon University, SEI