Download
oasis service oriented architecture reference model technical committee soa rm n.
Skip this Video
Loading SlideShow in 5 Seconds..
OASIS Service Oriented Architecture Reference Model Technical Committee (SOA-RM) PowerPoint Presentation
Download Presentation
OASIS Service Oriented Architecture Reference Model Technical Committee (SOA-RM)

OASIS Service Oriented Architecture Reference Model Technical Committee (SOA-RM)

185 Vues Download Presentation
Télécharger la présentation

OASIS Service Oriented Architecture Reference Model Technical Committee (SOA-RM)

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. OASIS Service Oriented Architecture Reference Model Technical Committee (SOA-RM) BOOT CAMP April 13 2005 DRAFT: Not approved by the OASIS SOA RM TC.

  2. Purpose • This slide deck is designed to bring new TC members up to speed. • Work described herein defines what we have consensus on at present time. • CAVEAT: Subject to change in future

  3. Agenda • What is SOA; what is a reference model for SOA • Why is a reference model needed • The OASIS SOA RM TC

  4. Defining SOA • If Service Oriented Architecture is Architecture, as the name implies, it should be definable as architecture. • This should not be done by referencing specific implementations. • Definition of Architecture (from Charter): • “Architecture: A software architecture for a system is the structure or structures of the system, which consist of elements and their externally visible properties, and the relationships among them.”

  5. Closer look: “Service Oriented” • Is a paradigm (model) for software architecture. • Focus herein is “software & systems architecture” • “Services” are the central concept; other concepts are present. • SOA not currently defined other than a “common law” or “defacto” perception of what it is. • Perceptions for definition of SOA are vastly disparate.

  6. What is a SOA Reference Model? • Is a model for developing a range of Service Oriented Architectures and analysis/comparison thereof. • Is not architecture for a single implementation. This is very important to understand since things you may see in other architecture might not be present in the Reference Model. • Is a framework for understanding significant relationships among the elements of a SOA environment. • Is based on concepts present in all SOA’s. • A Reference Model defines SOA in an abstract sense. Example: • Abstract = Service Description • Concrete = WSDL

  7. To develop a Reference Model for SOA • The TC is asking itself these questions: • What elements are common in all implementations of SOA? ( be careful – think about this) (Paraphrased) What are the core things that make SOA service oriented? • How do we describe those as abstract concepts? • What relationships exist amongst those concepts? • How do we represent those concepts without referencing concrete implementations.

  8. Draft Conceptual SOA Reference Model

  9. Base Components • Service: A behavior, or set of behaviors provided for use by another entity. • Service Description: A specification of the information necessary to: • allow a potential consumer to determine whether or not this service is applicable, and • facilitate invocation. • Advertisement: A methodology to convey awareness of (the existence of) a service(s) to all consumers on a fabric. Advertising makes discovery possible.

  10. Base Components and Concepts of SOA • Data Model: The logical expression of a set of information items associated with the consumption of a service or services. • Contract: The syntactic,  semantic and logical constraints governing on the use of a service.

  11. SOA Axioms • A Service is a set of functionality provided by one entity for the use of others. • Services are conceptually autonomous (self sufficient) and opaque (independent of underlying technology) in nature. • There is no need to make architectural distinctions between services that are consumed as part of a process vs. ones that are not. • There is not always a one to one correlation between “on the wire” requests to invoke a service and service responses being consumed. • Each logical Service has exactly one canonical Service Description.

  12. SOA Axioms • A Service Description is comprised of three logical parts - Data Model - The logical expression of a set of information items associated with the consumption of a service or services; - Policy - Assertions and obligations that service consumers and/or providers must adhere to or provide; and - Contract (and/or offer thereof) - the syntactic, semantic and logical constraints governing on the use of a service. • A security policy is a specialized type of the Service Description policy noted above. • Service Policy may mandate security requirements to be met, and if they are not, interaction (with the service) may be refused.

  13. SOA Axioms • A null security policy is still logically considered a policy. • A Service Description is advertised to consumers on a fabric to make it discoverable. • Discovery does not constitute authorization to execute against the service.

  14. Agenda • What is SOA; what is a reference model for SOA • Why is a reference model needed • The OASIS SOA RM TC

  15. Existing situation Question: How do I account for my requirements and organize components when building a concrete architecture? Requirements WS-* WS-Security WSDL WS-Trust XML & Schema Base Standards SOAP WS Addressing UDDI WS-RM Reg/Rep

  16. Thoughts on developing specific SOA’s • Probably not logical to try and develop a “one size, fits all” architecture for SOA or WS. • Not rational to develop multiple architectures in standards bodies for every set of requirements. • Best solution: develop an SOA reference Model. • Used by architects to guide development of specific service oriented architectures. • Model for a “way of thinking” when architecting. • Re-useable by multiple architects writing SOA for multiple domains. • Helps architects slot existing standards into their architectures.

  17. SOA RM used for range of architectures SOA-RM Guides developments of Specific Architectures Requirements Input for Uses WS-* WS-Security WSDL WS-Trust XML & Schema Base Standards SOAP WS Addressing UDDI WS-RM Reg/Rep

  18. Agenda • What is SOA; what is a reference model for SOA • Why is a reference model needed • The OASIS SOA RM TC

  19. OASIS SOA Reference Model TC • Chartered February 2005 • Problem to be solved: • "Service Oriented Architecture" (SOA) as a term is being used in an increasing number of contexts and specific technology implementations, sometimes with differing or conflicting understandings of implicit terminology and components. • The proposal to establish a Reference Model is intended to encourage the continued growth of specific and different SOA implementations whilst preserving a common layer that can be shared and understood between those or future implementations.

  20. OASIS SOA Reference Model TC • Purpose: • The SOA-RM TC will deliver a Service Oriented Architecture Reference Model (SOA-RM). • The TC may also create sub-committees, promotional material, liaisons or other promulgation of the TC's work, in order to promote the use of the SOA Reference Model. • May help vertical industries develop SOA for their requirements.

  21. Charter Definition • Reference Model: A reference model is an abstract framework for understanding significant relationships among the entities of some environment, and for the development of consistent standards or specifications supporting that environment. A reference model is based on a small number of unifying concepts. A reference model is not directly tied to any standards, technologies or other concrete implementation details, but it does seek to provide a common semantics that can be used unambiguously across and between different implementations.

  22. References • OASIS SOA RM TC - http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=soa-rm

  23. Other orientation activities • Review member submissions in our document repository. • Review glossary - http://www.tekni.ca/twiki/bin/view/SoaRefModel/SoaReferenceModelGlossary • Review SOA axioms - http://www.oasis-open.org/apps/org/workgroup/soa-rm/download.php/12246/SOA%20Axioms.pdf • Review message archives.

  24. Links to non-related Reference Models • 1. http://www.isotopicmaps.org/TMRM/TMRM-latest.html • Short and to the point. A good demonstration of how efficient and small a good reference model can be. • 2. http://www.isotopicmaps.org/tmrm/rm20031014.pdf • A Mathematical formula of the above Reference Model for Topic Maps • 3. http://www.dpconline.org/docs/lavoie_OAIS.pdf • The OAIS Reference Model overview. Another good example of a small, compact, lean reference model. • 4. http://www.x12.org/x12org/comments/X12Reference_Model_For_XML_Design.pdf • X12 reference model for XML. 120 pages – more technical. • 5. http://www.digitalearth.gov/derm/v05/derm05.pdf • This reference model actually brings together implementation technologies with abstract concepts. • 6. http://www.wfmc.org/standards/docs/tc003v11.pdf • Workflow Reference Model that includes specific technology – 55 pages