In this case, the bank loan atomic service plays the role of a routing proxy,
akin to the service facade architectural pattern.
Thus, consider the design implied relationship method when it is needed to further decouple
service functionalities. This design practice comes in handy in interoperable computing environments
where intermediaries provide protocol and data conversions, encourage reusability of
individual services, or intercept messages for security purposes.
ISOLATED CONTAINMENT DESIGN RELATIONSHIP. Recall that in the service conceptualization
and the service discovery and analysis phases (Parts Two and Three, respectively), aggregation
capabilities of composite services and service clusters were explored. It was then found that these
structures typically link their contained services and leverage their collaborative capacities to
240 Ch. 12 Service-Oriented Logical Design Relationship
Bank
Loan
Atomic
Service
Small
Business
Loan
Atomic
Service
Small
Business
Loan
Consumer
Individual
Loan
Atomic
Service
EXHIBIT 12.4 IMPLIED BIDIRECTIONAL DESIGN RELATIONSHIP
provide solutions. This containment scheme, however, can also be used to provide protection to
internal services by isolating them from remote consumers or external services.
Consider, for example, a containment structure, as depicted in Exhibit 12.5. The composite
service intraday reporting is made up of two other smaller, fine-grained services: the equity trading
intraday reporting service and the mutual funds reporting service.
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