1. Service Oriented Design III Service Oriented Design 605.702 Service Oriented Architecture Johns-Hopkins University Montgomery County Center, Spring 2009 Lecture 11: April 20, 2009 Instructor: T. Pole

2. Agenda (for the week) Tonight, 4/20/09 –Ch 15: Service Oriented Design Part II Service Design –Review Analysis and Design Chapters 11 through 15 Wednesday, 4/22/09 –Example Project, Analysis and Design Templates Not complete artifacts, just outlines –Reusable/Legacy Components, version 2 –Class Project Working Session

3. Ch 15: Service Oriented Design Part III Service Design Overview of Goals and Strategy Goals –Encapsulate the required logic –Conform to service oriented principles –Meet business requirements Strategy, order of steps –Design entity centric services –Design application services –Design task centric business oriented services –Design process services Control services, orchestrations and choreographies More details later in this lecture

4. Review Analysis and Design Chapters 11 through 15 –Service Oriented Analysis –Service Modeling –Service Oriented Architecture Composition –Service Design

5. Service Oriented Analysis Primary questions: –What services need to be built? –What logic should be encapsulated by each service? Overall goals (i.e. steps or tasks): –Define preliminary set of service OPERATION candidates –Group operation candidates into logical contexts which are candidate services –SO Principles: Identify reuse potential Ensure contexts make sense (have a logical basis) Identify issues that may impact service autonomy Define known preliminary composition models

6. Service Modeling Model Candidate Services –Decompose business processes –Identify automatable process steps Also known as, filter out unsuitable steps –Differentiate between process-agnostic and process- specific logic –Identify candidate service composition –Identify, refine and finalize definition of service candidates –Identify, refine and finalize definition of services compositions

7. Text Book: Service Modeling Case Study 12.4 Contrasting service modeling approaches (an example) –Approach #1: Deriving hybrid services –Approach #2: Deriving entity-centric services –Approach #3: Mixing task-centric and entity-centric services

8. Service Oriented Architecture Composition Compose SOA –Choose Service Layers Existing Services, SOA applications, etc. Enterprise Standards Composition Performance Considerations –Position Core Standards Industry Standards –Will you use UDDI? –Choose SOA Extensions Which extensions will you use in which compositions?

9. Service Design Entity-Centric Business Service Design Process –Establish the business service layer, fig 15-1 –Case study pp 503-521 Application (Utiltiy) Service Design Process –Establish the utility service layer, fig. 15-10 –Case study pp 524-538 Task-Centric Business Service Design –Complete the business service layer(s), fig. 15-15 –Case study pp 541-554 Process (Control) Service Design –Establish the control layer –Chapter 16 – mostly but not completely beyond the scope of the class project

10. Entity-Centric Service Design Review existing services Define entities (schema) Define abstract interface Apply Service Oriented principles Standardize service interface Extend service design Identify other (non-entity) services

11. Application (Utility) Service Design Review existing services Confirm context Derive candidate (initial) interface Apply service oriented principles Standardize service interface App “speculative” features

12. Task-Centric Design Service Define workflow logic Define initial interface Apply service oriented principles Standardize service interface Identify other required services

13. Control Service Design