Which statement best describes the relationship between a Service Contract and a Usage
Agreement as defined by the Oracle Reference Architecture (ORA)?
A.
There is a one-to-one relationship between a Service Contract and a Usage Agreement. For
each Service Contract there is a corresponding Usage Agreement.
B.
There may be multiple Usage Agreements associated with a single Service Contract.
C.
There may be multiple Service Contracts associated with a single Usage Agreement.
D.
There is a many-to-many relationship between Service Contracts and Usage Agreements.
E.
There is no defined relationship between a Service Contract and a Usage Agreement.
Explanation:
The Service Contract defines what the SOA Service agrees to provide to the
environment.
The service consumer Usage Agreement defines what a particular service consumer is
entitled to consume.
Each service might have several consumers.
The Service provider must ensure that the Service will satisfy the aggregate
specifications of all related usage agreements.
Note:
The usage agreement is not part of the Service; rather it defines what a particular service
consumer is entitled to consume from the Service.
Having both a usage agreement and a service contract provides a decoupling between
the service provider and service consumer. This not only facilitates reuse but also
provides a separation of concerns. The service contract defines the totality of what the
Service guarantees to provide, and can be written and validated independent of any
knowledge of specific service consumers. The usage agreement is service consumer
specific and defines what capabilities of the Service each consumer is allowed to
consume.
Reference: Oracle Reference Architectureand Service Orientation, Release 3.0