An Efficient Approach to Support Querying Secure Outsourced XML Information

  • Yin Yang
  • Wilfred Ng
  • Ho Lam Lau
  • James Cheng
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4001)


Data security is well-recognized a vital issue in an information system that is supported in an outsource environment. However, most of conventional XML encryption proposals treat confidential parts of an XML document as whole blocks of text and apply encryption algorithms directly on them. As a result, queries involving the encrypted part cannot be efficiently processed. In order to address these problems, we propose XQEnc, a novel approach to support querying encrypted XML. XQEnc is based on two important techniques of vectorization and skeleton compression. Essentially, vectorization, which is a generalization of columns of a relational table, makes use the basic path of an XML tree to label the data values. Skeleton compression collapses the redundant paths into a multiplicity attribute. Our analysis and experimental study shows that XQEnc achieves both better query efficiency and more robust security compared with conventional methods. As an application, we show how XQEnc can be realized with relational techniques to enable secure XML data outsourcing.


Query Processing Encrypt Data Cipher Text XPath Query Query Translator 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Yin Yang
    • 1
  • Wilfred Ng
    • 1
  • Ho Lam Lau
    • 1
  • James Cheng
    • 1
  1. 1.Department of Computer ScienceHong Kong University of Science and Technology 

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