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P. Bierleutgeb:
"VRoxy: Enriching SOAs with proxy-based dynamic binding and reporting based on VRESCo";
Supervisor: S. Dustdar, Ph. Leitner; Institut für Informationssysteme, AB Verteilte Systeme, 2011.

In the past few years, Service Oriented Architectures (SOA) have become increasingly popular, as they promise to solve vital challenges of large, distributed enterprise systems, such as
heterogeneity and enabling loose coupling.
However, the anticipated decoupling of services and clients has not been fully achieved, as the publish-find-bind triangle, which suggests the dynamic discovery and selection of services,
is partially broken. Furthermore, many service-based systems miss sophisticated monitoring and reporting capabilities. As a consequence, it is hard to keep track of deployed services and the
complex net of invocations and service dependencies.
VRESCo - the Vienna Runtime Environment for Service-oriented Computing - aims to overcome these limitations by providing support for dynamic service discovery and binding. However, the framework currently only exists as a research prototype that has never been tested in large, real-life enterprise systems. An employment in such systems would prove beneficial for further research, but is impeded by the high complexity an installation would cause.
In this thesis, a proxy-based solution for the interception, analysis, correction and monitoring of Web service requests is introduced. VRoxy (VRESCo Proxy) enables the transparent
employment of VRESCo, by releasing clients of the responsibility to communicate with the registry on their own. Instead, VRoxy intercepts requests sent by clients, and uses the information contained in the SOAP message to query VRESCo for matching service revisions. Thus, VRoxy is able to update the endpoint used in the original request, and redirect the invocation to theWeb service endpoint stored in VRESCo. The presented prototype can be configured using different
interceptors and querying strategies in order to provide suitable functionality for various use cases.
Furthermore, since all traffic between clients and services passes through the proxy, VRoxy is capable of monitoring general connection data (e.g. time of invocation) and Quality of Service (QoS) specific properties ofWeb service invocations. The gathered monitoring data is presented in form of informative and interactive reports. The provided reports can be viewed using the VRESCo Reporting Web application which offers convenient navigation and input forms for the specification of report parameters.