SOA Reference Architecture – Relationship to Other SOA Standards
The “Navigating the SOA Open Standards Landscape Around Architecture” joint White Paper from OASIS, OMG, and The Open Group  was written to aid the SOA community navigate the myriad of overlapping technical products produced by these organizations with specific emphasis on the “A” in SOA; i.e., Architecture.
This joint White Paper explains and positions standards for SOA reference models, ontologies, reference architectures, maturity models, modeling languages, and standards work on SOA governance. It outlines where the works are similar, highlights the strengths of each body of work, and touches on how the work can be used together in complementary ways. It is also meant as a guide to users of these specifications for selecting the technical products most appropriate for their needs, consistent with where they are today and where they plan to head on their SOA journeys.
While the understanding of SOA and SOA governance concepts provided by these works is similar, the evolving standards are written from different perspectives. Each specification supports a similar range of opportunity, but has provided different levels of detail for the perspectives on which they focus. Therefore, although the definitions and expressions may differ somewhat, there is agreement on the fundamental concepts of SOA and SOA governance.
The following is a summary of the positioning and guidance on the specifications:
- The OASIS Reference Model for SOA (SOA RM) is the most abstract of the specifications positioned. It is used for understanding core SOA concepts. (See .)
- The Open Group SOA Ontology extends, refines, and formalizes some of the core concepts of the SOA RM. It is used for understanding core SOA concepts and facilitates a model-driven approach to SOA development. (See .)
- The OASIS Reference Architecture for SOA Foundation is an abstract, foundation reference architecture addressing the ecosystem viewpoint for building and interacting within the SOA paradigm. It is used for understanding different elements of SOA, the completeness of SOA architectures and implementations, and considerations for cross-ownership boundaries where there is no single authoritative entity for SOA and SOA governance. (Refer to: http://docs.oasis-open.org/soa-rm/soa-ra/v1.0/soa-ra-pr-01.pdf.)
- The Open Group SOA Reference Architecture (this document) is a layered architecture from a consumer and provider perspective with cross-cutting concerns describing those Architecture Building Blocks (ABBs) and principles that support the realizations of SOA. It is used for understanding the different elements of SOA, deployment of SOA in the enterprise, the basis for an industry or organizational reference architecture, implication of architectural decisions, and positioning of vendor products in SOA context.
- The Open Group SOA Governance Framework is a governance domain reference model and method. It is for understanding SOA governance in organizations. The OASIS Reference Architecture for SOA Foundation contains an abstract discussion of governance principles as applied to SOA with particular application to governance across boundaries. (See .)
- The Open Group SOA Integration Maturity Model (OSIMM) is a means to assess an organization’s maturity within a broad SOA spectrum and defines a roadmap for incremental adoption. It is used for understanding the level of SOA maturity in an organization. (See .)
- The Object Management Group SoaML Specification supports services modeling UML extensions. It can be seen as an instantiation of a subset of The Open Group SOA Reference Architecture used for representing SOA artifacts in UML. (Refer to: www.omg.org.)
SOA Reference Architecture Positioning
Fortunately, there is a great deal of agreement on the foundational core concepts across the many independent specifications and standards for SOA. This could be best explained by broad and common experience of users of SOA and its maturity in the marketplace. It also provides assurance that investing in SOA-based business and IT transformation initiatives that incorporate and use these specifications and standards helps to mitigate risks that might compromise a successful SOA solution.
It is anticipated that future work on SOA standards may consider the positioning in this document to reduce inconsistencies, overlaps, and gaps between related standards and to ensure that they continue to evolve in as consistent and complete a manner as possible.