The service model is an abstraction of the IT services implemented within an enterprise. It supports the development of
one or more service-oriented solutions. It is used to conceive and document the design of the software services. It is
a comprehensive, composite work product encompassing all services, providers, specifications, partitions, messages,
collaborations, and the relationships between them. It is needed to:
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Identify candidate services and capture decisions about which services will actually be exposed
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Specify the contract between the service provider and the consumer of the services
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Associate Services with the components needed to realize these services
The Service Model captures the details of a set of services. It can be created and maintained across the lifetimes of
one or many projects. The service model can be used for different levels of scope:
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Service-scoped development where the scope of the project is to develop the service independently
(as much as possible) from other services. The modeling would therefore encompass the use cases, architecture,
design and implementation models as a vertical slice for the one service.
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Project-scoped development where a project involves the specification of a number of services to
support a set of application or business process requirements. In this case, the scope is broadened to
the application/business process level. It might involve several services. In effect, there is a set
of models for use cases/business processes and architecture, and then there is a set of service-specific
design and implementation models.
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Enterprise-scoped development, or service portfolio management, where the scope is only to capture
the service specifications and logical partitioning, but at an enterprise-wide scope. This allows designers and
architects to make wide ranging decisions about the entire portfolio, yet separate projects are required to develop
the design and implementation models for the identified services (and client applications and/or business
processes).
The following diagram demonstrates the key aspects of the Service Model, abstractly, and the relationship between them
and the Identification, Specification, and Realization activities that are part of the service solution design
lifecycle:
The service model is often a heterogeneous collection of physical assets, including UML models, documents, and possibly
entries in a requirements management tool. However, the service model has to address the items listed in the above
diagram.
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