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A new structure for streaming the XML data is proposed which guarantees confidentiality of the XML data over the wireless stream.An access mechanism is proposed to efficiently process XML queries over the encrypted XML stream. Recently, the use of XML for data broadcasting in mobile wireless networks has gained many attentions. One of the most essential requirements for such networks is data confidentiality. In order to secure XML data broadcast in mobile wireless networks, mobile clients should obey a set of access authorizations specified on the original XML document. In such environments, mobile clients can only access authorized parts of encrypted XML stream based on their access authorizations. Several indexing methods have been proposed in order to have selective access to XML data over the XML stream. However, these indexing methods cannot be used for encrypted XML data. In this paper, we define a new structure for XML stream which supports data confidentiality of XML data over the wireless broadcast channel. We also define an access mechanism for our proposed structure to efficiently process XML queries over the encrypted XML stream. The experimental results demonstrate that the use of our proposed structure and access mechanism for XML data broadcast efficiently disseminates XML data in mobile wireless networks.

XML has recently become very popular as a means of representing semistructured data and as a standard for data exchange over the Web, because of its varied applicability in numerous applications. Therefore, XML documents constitute an important data mining domain. In this paper, we propose a new method of XML document clustering by a global criterion function, considering the weight of common structures. Our approach initially extracts representative structures of frequent patterns from schemaless XML documents using a sequential pattern mining algorithm. Then, we perform clustering of an XML document by the weight of common structures, without a measure of pairwise similarity, assuming that an XML document is a transaction and frequent structures extracted from documents are items of the transaction. We conducted experiments to compare our method with previous methods. The experimental results show the effectiveness of our approach.

Since the turn of the millenium, working groups of the W3C have been concentrating on the development of XML-based security standards, which are paraphrased as XML security. XML security consists of three recommendations: XML (digital) signature, XML encryption and XML key management specification (XKMS), all of them published by the W3C. By means of a review of the available literature the authors draw several conclusions about the status quo of XML security. Furthermore, the current state and focuses of research as well as the existing challenges are derived. Trends to different application areas - e.g. use of XML security for mobile computing - are also outlined. Based on this information the analyzed results are discussed and a future outlook is predicted.

Due the popularity of XML, an increasingly large amount of business transactions encoded in XML have been exchanged on-line. Currently there are two approaches to process and manage these XML data. One is to store them in relational databases, and the other is to store them in recently-developed native XML databases. There is no conclusion yet as to which approach suits better for contemporary business information systems. Also, the effectiveness of native XML databases used in daily operational systems has not been completely investigated. Therefore, in this paper, we provide: (1) a complete and systematic survey of the current development and challenges of processing XML data in relational and native XML databases, (2) a useful benchmark for IT practitioners who need to process XML data effectively, (3) experimental results and detailed analysis which reveal several interesting tips that can be helpful to XML document designers, and (4) a conclusion, based on the findings of using native XML databases in EDI processes, that it is practical to use native XML databases for daily operations although our experimental results showed that relational database systems outperform native XML databases in processing XML data.