Abstract:
Unlike components, Web Services are primarily intended for interenterprise
applications that use Internet as the underlying transport mechanism,
and consequently are subject to a different set of design considerations than intra-
enterprise applications. Most practitioners recommend the use of coarse grained.
message-oriented Web Service that minimize the number of messages
and avoid the need to maintain state information between invocations. In this
paper we argue that excessive use of coarse-grained, document-centric message
structures results in poor reuse and undesirable interdependencies between services.
We describe a design approach that provides a framework for designing
message payloads for service-oriented applications. We treat the problem of
message design from a data engineering perspective and apply data normalization
techniques to the design of service interfaces. We consider the impact of
increasing message granularity on cohesion and coupling of service operations
and discuss the associated design tradeoffs.
