1 Xinke Lin Andreas Häber Veena Dodballapur Demystifying SOA and EDA

2 Overview  Driving forces for new architecture styles  Architecture Style, Advantages and Limitations SOA EDA  Comparison and Complementary aspects  Fabricated Case Study

3 Driving Forces Complexity Integration of Heterogenous Components Number of Interfaces Reuse of Code Meet Requirements at low Costs

4 Issues With Existing Systems  Tightly Coupled  Too Static  Inflexible  Not Extensible  Not Standardized

5 SOA: Service Oriented Architecture

6 Service Oriented Architecture  Definition “The set of components which can be invoked and whose interface definitions can be published and discovered.“ (W3C)  Is it new ?  Distributed Computing  CORBA

7 Service Oriented Architecture Architectural Elements Producers Consumers Contract Service Repository Transport

8 SOA Characteristics  Discoverable and dynamically bound  Self-contained and modular  Interoperability  Loosely coupled  Coarse-grained interfaces  Location-transparent

9 SOA In Real World  Web Services Web services specifies guidelines on how services interact; that is, it is the tactical implementation of an SOA model most commonly seen in SOAP messages delivered over HTTP.  Examples Financial Systems – Credit Card Checking B2B Communication

10 SOA - Advantages  Business Benefits Can respond quickly to marketplace changes Improves customer service Business flexibility  IT Benefits Gives a more responsive IT organisation Decreases development and deployment cycle times Reduces maintenance costs Enhances existing IT systems

11 SOA - Limitations  Team management  SOA is good only for interactions of logically 'separate' systems  Not a solution for all problems Many-Many Communication Push Model Asynchronous communication

12 EDA: Event-Driven Architecture

13 Event Driven Architecture  Definition “The term event driven architecture refers to any application that can detect report and react intelligently to changes in condition.”

14 EDA - Features  Individually captures unpredictable, asynchronous events occurring in parallel  Senses real-time events and conditions in business environment/databases  Initiates appropriate response, action, or process  Modifies processes in real-time for optimal response to changing conditions

15 Forces Behind EDA Development  Business Demand Event Driven Design  SOA promotes EDA  Vendors offering Enabling Tools  Standards  Infrastructure and Network technology has improved a great extent

16 EDA - Characteristics Publish – Subscribe –Notify Subscribers selectively De-coupled –No Contract –Publisher and Subscriber have no knowledge –Asynchronous Push Communication Many to many

17 EDA – Architectural Elements Architectural Elements –Event Receptors –Event Processors –Transport –Event Management Application Program Interfaces

18 EDA – Implementation Styles Simple Event Driven –Simple MOM Middleware Event Driven Applications with Integration brokers –Business Process Management Complex Event Processing –Business Activity Monitoring

19 EDA - Advantages  Maintainability  Same Data needs to reach many destinations  Integration  Reusability  Reduced Costs  Stakeholder Communication

20 EDA - Limitations  Team management  Incomplete Standards  Testability  Inexperience of Architects  Not a solution for all problems

21 Comparison and complementary aspects of SOA and EDA

22 Comparison of SOA and EDA AttributeSOAEDA CouplingLoosely coupledDecoupled ConnectionOne-oneMany-Many Flow InitiationFlow directed by sender Flow directed by the sink of the recipient Execution Path Linear execution path Request – response exchanges Supports dynamic asynchronous calls through a network of modules Response to Unforeseen Events Closed to new unforeseen output once the flow starts Adaptable to new events

23 Why they complement each other  Does not need to be Mutually Exclusive  Events invoking Services or Triggered by Services  EDA’s being Service Oriented  Standard sharing  Different use of data

24 Enterprise Application Design Trends

25 Use cases

26 Enterprise Service Bus

27 Fabricated Use Case – Medical System  “MRS” is a major referral hospital and offers a comprehensive range of community health services. It has a number of physicians working in different areas.  The hospital is the consumer and provider of services to a number of people, organizations and institutions. One of the challenges the hospital faces is the number of manual processes it has to cope with.  The challenge of the new architecture is to simplify the workflows and eliminate many processes, replacing them with automated applications.  Some Goals Reduce risk, Accelerate transaction settlement Provide extensibility and easy integration of existing and new components Be scalable

28 Scenarios Considered  Requesting services from the laboratory to examine tests.  Referring patients to the hospital.  Re-ordering of medicines automatically when they go out of stock  Billing of insurance companies when the patient has any insurance claims.  Providing up-to-date information for doctors in the hospital about new drugs.

29 Services – Solution  Drug Supplies Services track of drug information, stock etc  Patient Referring Services refer a patient to the hospital.  Insurance Services insurance aspects of the system.  Pharmaceutical Advertising Services notify subscribers about new drugs  Laboratory Services clinical and microbiological services

30 Architecture Diagram (1 of 2)

31 Architecture Diagram (2 of 2)

32 Conclusions

33 Conclusion  Business Processes, their management and design will certainly be benefited by SOA and EDA  Enormous financial and strategic benefits to enterprises obtained by implementing them  EDA and SOA have distinct styles  Enterprises will be benefited by looking at them as complementary architecture styles

34 Questions ??