Service-Oriented Architecture (SOA) is an application architecture designed to achieve loose coupling among interacting software applications. Using Web Service technology a distributed application can be created in a heterogeneous environment. The ultimate goal of SOA is to be able to write applications independently of the concrete services used and to select and to integrate services on the fly. Currently, web services are described in WSDL-format and published in a registry. Service clients can browse these registries to find a matching service and determine how to communicate with it.