Capability Pattern: Service Identification
Identify candidate services using both top-down (business-oriented) and bottom-up (existing asset-oriented) approaches.
Work Breakdown Structure
Description

This is a "project-scope" workflow; the assumption is that the project continues with Service Specification activities.  If a project is being executed where service identification results are the end products, consider performing the "Service Litmus Testing" activity from the Rational SOMA Service Specification practice as the terminal activity in the workflow.  Doing so provides you with a ready list of services to be defined and implemented during future endeavors.

The workflow begins with goal-service modeling, to help emphasize the importance of ensuring that the SOA ties back to the business strategy.  If you are beginning with an empty candidate service portfolio, it might be difficult to describe meaningful, goal-fulfilling candidates that also fit well with candidates discovered during the other activities, such as Business Model Analysis.  You can address this issue in a number of ways, including:

  • Pay particular attention during refactoring activities to the need to reconcile the services discovered during goal-service modeling with the services discovered during other activities; or
  • Delay goal-service modeling.  In some cases, it can be useful to dispense with the initial Goal-Service Modeling activity entirely, and focus on using the second instance, which ends the illustrated workflow, as a "catcher" activity to ensure that each goal is served by a candidate service.
Key Considerations

The workflow diagram illustrates an optional second round of goal-service modeling at the end of System Identification.  This is performed only if there is a need to either:

  • re-confirm that all sub-goals have been addressed by at least one service, or
  • allocate newly discovered candidate services to sub-goals.
Workflow

Activity diagram: Service Identification Goal-Service Modeling Domain Decomposition Existing Asset Analysis Refactor the Candidate Service Model Goal-Service Modeling

Activity detail diagram: Service Identification SOA Architect Goal-Service Modeling Refactor the Candidate Service Model Goal-Service Modeling SOA Architect Service Model [Business Requirements] Goal-Service Modeling Goal-Service Model Goal-Service Modeling Service Model System-Wide Requirements Refactor the Candidate Service Model Service Model Refactor the Candidate Service Model Service Model [Business Requirements] Goal-Service Modeling Goal-Service Model Goal-Service Modeling
Work Breakdown