By the increase in number of available Web services over the internet, accessing a required web service becomes a challenging task. One solution to the problem is using distributed web service discovery system that is composed of domain specific sub service discoverers. Using ontology is the most common practice to specify domain knowledge. Domain specific subsystems form an unstructured P2P network that connects nodes to each other in order to facilitate cross domain web service query routings. In this paper, we present a networking infrastructure of a distributed web service search system and its ontology-based routing method, We evaluate the performance of ontology-based routing method by using both complete and brief version of ontology of the domain specific discoverer under basic and normalized semantic similarity measures in terms of traffic improvement, and accuracy of the forwarded web services. Experimental evaluation shows that the traffic is reduced by 50% with the web service forwarding precision of 90%.