What is SOA? IT architecture for request - reply applications Application functions are modularized and presented as services Services are loosely coupled – Service interface is independent of the implementation

SOA Slides © Raghu Kodali andWebServices.ppt

Service-oriented architecture (SOA) definition “A service-oriented architecture is essentially a collection of services. These services communicate with each other. The communication can involve either simple data passing or it could involve two or more services coordinating some activity. Some means of connecting services to each other is needed.” ( oriented_architecture_soa_definition.html) Many other definitions can be found

Characteristics of SOA Services have platform independent, self describing interfaces (XML) Messages are formally defined Services can be discovered Services have quality of service characteristics defined in policies Services can be provided on any platform SOASOA Interoperable Loosely Coupled Re-Usable Composable

Why SOA? – The Cruel Reality Source: Gartner

OracleFinancials Standard Interface Custom Order Application Standard Interface New Web Application Application Standard Interface SiebelCRM Mainframe HR Application Standard Interface.NET Inventory Application Standard Interface New Supply Chain Management Application (Business Process or Composite Application) Why SOA? Respond to business changes Address new needs with existing applications Unlock existing application investments Support new channels & complex interactions Support organic business

Anatomy of a Service Service Consumer Interface Proxy ServiceInterfaceServiceImplementation New Service WrappedLegacy CompositeService

Service Consumers Service Producers Service Communication Communicate with messages No knowledge about partner Likely heterogeneous

Service Interfaces and Service Implementations Service Consumers Service Delivery Bus Service Rules & Config Change Service Platform Control Service Reporting & Mgmt

Benefits of SOA Better reuse – Build new client functionality on top of existing Business Services Well defined interfaces – Make changes without affecting clients Easier to maintain – Changes/Versions are not all-or-nothing Better flexibility

Services Communicate With Messages Providing reliability and security to messages Sending messages across consumers and producers Service Orchestration Service Consumers Service Producers

WSDL Web Service (J2EE, PL/SQL,.NET,C/C++, Legacy …) Web Service (J2EE, PL/SQL,.NET,C/C++, Legacy …) Web Service Client (J2EE,.NET, PL/SQL …) Web Service Client (J2EE,.NET, PL/SQL …) Points to description Describes Service Finds Service Invokes with XML Messages Basic Web Services SOAP UDDI Registry Points to service