Soa 7 soad elements
- 1. Service Oriented Architecture: 7 SOAD Elements Prof Neeraj Bhargava Vaibhav Khanna Department of Computer Science School of Engineering and Systems Sciences Maharshi Dayanand Saraswati University Ajmer
- 2. Layers in Software Analysis and Design
- 3. Service identification and definition • SOA solution almost always involve integrating existing legacy systems by decomposing them into services, operations, business processes, and business rules • Existing applications and vendor packages are factored into sets of discrete services that represent groups of related operations (bottom- up approach). • Business processes and rules are abstracted from the applications into a separate BPM, managed by a business choreography model.
- 4. Service Decomposition All OOAD techniques can be applied in relationship to identifying and defining a service; however, a higher viewpoint needs to be taken.
- 5. Direct and indirect business analysis • Direct Analysis: BPM and direct requirements analysis through stakeholder interviews • Indirect Analysis: When mining for candidate services, product managers and other business leaders should be interviewed • Any existing use case models from non-SOA projects should also be consulted.
- 6. Domain decomposition • Domain decomposition, subsystem analysis, goal model creation, and related techniques are a first promising proposal for a SOA process structuring method. • granularityTo select the right level of abstraction is a key service modeling issue • Another option is the bundling of several related services into coarser-grained service definitions
- 7. Naming conventions • An enterprise-wide naming scheme (XML namespaces, Java package names, Internet domains)should be defined. • A simple example would be to recommend always assigning a service with a noun, and its operations with verbs. • This best practice originates from the OOAD space
- 8. SOAD elements • Service categorization and aggregation • Policies and aspects • Meet-in-the-middle processes • Semantic brokering • Service harvesting and knowledge brokering
- 9. SOAD elements • Service categorization and aggregation :Services have different uses and purpose – Atomic services can be orchestrated (composed) into higher level, full-fledged services • Policies and aspects: A service has syntax, semantics, and QoS characteristics that all have to be modelled; • Business traceability is a desirable quality, in addition to the well-established principle of architectural traceability
- 10. SOAD elements • Process: meet-in-the-middle: • The bottom-up approach tends to lead to poor business-service abstractions in case the design is dictated by the existing IT environment, rather than existing and future business needs. • On the other hand, top-down processing might cause insufficient, non-functional requirement characteristics
- 11. SOAD elements • Semantic brokering: In any SOA context, a formal interface contract for the invocation syntax is important. • The semantics issue (the meaning of parameters and so forth) has to be solved as well (domain modeling). • This is key in any business-to-business (B2B) and dynamic invocation scenario.
- 12. SOAD elements • Service harvesting and knowledge brokering: • This is a knowledge management and lifecycle issue: how can services successfully be prepared and made available for reuse once they have been conceptualized? • Services should be identified and defined with reuse (and harvesting) as one of the main driving criteria of the SOA in mind. • If a component (or service) has no potential for reuse, then it should probably not be deployed as a service.
- 13. Assignment • Discuss in Detail the SOAD Elements and their usage. • Thank You