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Recent modeling frameworks for semantically enriched web services propose a
layered architecture of di.erent functionalities and representations. For discovery,
selection, and composition of web services, an adequate semantic representation
and a transport layer are (among others) necessary elements [1]. The semantic
layer takes care of a shared understanding between requester and provider
in order to enable automatic service provisioning. The most current approaches
propose to utilize ontologies for this task [2]. The far end with respect to semantics
is the transport layer, which specifies the details of how to access and
communicate with the service implementation on a technical level. In order to
invoke a service both layers need to be connected for data hand over between
each other. This requires a mapping from an abstract semantical model to a
concrete service specification in terms of a particular protocol, message format,
data types, and serialization. We argue, that this bi-directional mapping, also
called grounding, cannot be done syntactically as proposed by the OWL-S [3]
service framework for example. This problem of linking declaratively specified
parameter descriptions with primitive types (XML Schema in case of WSDL [4])
largely has been neglected in current semantic web services frameworks. In order
not to limit the portability and practicability of current framework specifications
we aim to bring this issue to the fore. In the following we will describe the mismatch
of syntax-based groundings and propose a semantic mapping framework
for which we refer to an existing algorithm and shortly describe our mapping
editor.
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