XML is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable, the increasing availability of heterogeneous XML informative sources has raised a number of issues concerning how to represent and manage semi-structured data. Although XML sources can exhibit proper structures and contents, differently annotated XML documents may in principle encode related semantics due to subjective definitions of markup tags. Discovering ontology knowledge to infer semantic organization of XML documents has become a major challenge in XML data management. XPath query language is used for selecting nodes and compute values from XML document, tuple the XML tree and address the problem of XML data clustering according to structure with lexical ontology knowledge. SOAP is a protocol specification for exchanging structured information in the implementation of web services in computer networks, in literature it relies on HTTP for message negotiation and transmission. Experiment on real XML database gives evidence that our proposed approach is highly effective in tuples and clustering of XML database, also aims to study the effect of digital signature on the SOAP messages. So this paper proposes two models consist of a Server and a Client connected to each other through a Wireless router over TCP protocol, XML data base is a sample of DBLP with size of 10 MB loaded on the Server and SOAP messages are used to communicate between both terminals. Finally we compared results between No. of replayed nodes, time and XPath queries, also compared the effects of unsigned and signed SOAP messages .
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