A Proposed "Services Reference Architecture"

The proposed Services Reference Architecture (SRA) describes how an operational or functional community plans to implement web services and service-oriented architecture to support the performance of its joint functional mission.  It is called a reference architecture because it is meant to serve as a roadmap and reference to community stakeholders on how to incorporate web services and associated considerations into their respective acquisition, engineering, development, and implementation efforts.  The standards in the document may or may not be prescriptive.

The SRA should include a description of

·         the services to be implemented (SvcV-1, SvcV-2, SvcV4*), based on the required capabilities defined in an Operational Architecture

·         by whom and where they will be implemented, notionally (SvcV-3a)

·         functionality and information exchanges facilitated or performed via the services (SvcV-5). 

·         data elements used in the services (SvcV-2, SvcV-6).  Ideally, these data elements are from existing data models, schemas, ontologies, or other approved data artifacts.

·         service relationships and dependencies (SvcV-3b, SvcV-10c)

·         service standards to be applied by service developers (SvcV-7, SvcV-9).  This may include mandated standards (e.g., from higher level external agencies and activities), recommended standards (where multiple standards are acceptable), and emerging standards that are being considered for adoption.

·         services terms of reference, which is simply a list of key terms and concepts used in the document, along with their definitions.

·         guiding principles for service development and implementation, to include criteria for assessing the suitability and acceptability of services being considered for adoption, being developed, being operationally evaluated, or being used.

The SRA may include, as optional elements,

·         Identification of enterprise (i.e., non-community specific) services to be adopted by the community (SvcV-3b).

·         Existing, planned, and developmental services that meet interim or objective community service requirements (SvcV-3b).

·         Service development and implementation priorities (SvcV-8).  [NOTE: This product may be considered a mandatory component of a prescriptive SRA, but is optional for an SRA that is only descriptive.]

·         A high level operational concept graphic and description to place the referenced services in an operational context (OV-1).

·         A description of the operational benefits to be gained from each service, service “string” and the set of services as a whole.

·         A discussion of possible trade-offs among services with similar or overlapping capabilities.

·         Standard verbiage to be inserted into solicitations and RFPs.

The SRA should not include

·         The assignment of specific service development responsibilities to individual programs of record (May be included in a follow-on Services Implementation Plan)

·         Any discussion of service development costs (May be included in a follow-on Services Implementation Plan, or may be deferred to individual implementing agents.) 

*The DODAF architecture view annotations are for reference, only. The Services Reference Architecture may actually be formatted as a standard textual artifact with appropriate graphics, and need not include DODAF view designations.