A web service already defines each business or
functional service
interface and its endpoints in a WSDL document. A
web service can also define each manageability
service interface and its endpoints in a WSDL document.
A WSDL document defining a manageability service describes each
interface upon which a web service offers management information. Such a WSDL document may be published to and
advertised by a discovery agency visible to the appropriate consumers
of the described
manageability service.
The consumer of a manageability service may be
offered interfaces
to retrieve configuration and metric data, and offered interfaces to
update the
configuration of the service. The
consumer of a manageability service may also be offered an interface to
receive
events from a service or a resource represented by the manageability
service. Other components of the web services
architecture may offer this consumer additional manageability service
interfaces
and endpoints as well.
Often, it is desirable that consumers of a
business or a functional
service do not have access to, or awareness of, the manageability
interfaces
for that service. Often, it is desirable
that consumers of a manageability service do not have access to the
business or
the functional interfaces, and any underlying resources, represented by
the
manageability service. Thus, it is likely
that a functional service and its corresponding manageability service
are each advertised
to a mutually exclusive set of consumers.
Advertisements of a functional service may be
visible on an
external services portal expressly for consumers of the functional
service. Advertisements of the corresponding
manageability
service may be visible on an internal services portal expressly for
consumers
of the manageability service. However, other service advertisement
combinations
are readily supported. For example, a
subset of the capabilities of a manageability service may be advertised
on the
external services portal to the consumers of the corresponding
functional
service.
The above considerations provide a motivation
for the
following variation on the web services oriented architecture triangle: