Collaboration-Preserving Authenticated Encryption for Operational Transformation Systems

  • Michael Clear
  • Karl Reid
  • Desmond Ennis
  • Arthur Hughes
  • Hitesh Tewari
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7483)


We present a flexible approach for achieving user-controlled privacy and integrity of documents that are collaboratively authored within web-based document-editing applications. In this setting, the goal is to provide security without modifying the web application’s client-side or server-side components. Instead, communication between both components is transparently intercepted and processed (if necessary) by means of a local proxy or browser plugin. We improve upon existing solutions by securely preserving real-time collaboration for encrypted documents and facilitating self-containment of the metadata (an overhead of encryption) within the same document. An architectural generalization is also presented that permits generic transformations and fine-grained access control. Security is assessed with respect to several threat models, and performance is evaluated alongside other approaches.


Range Query Homomorphic Encryption Threat Model Computer Support Cooperative Work Document Content 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Michael Clear
    • 1
  • Karl Reid
    • 1
  • Desmond Ennis
    • 1
  • Arthur Hughes
    • 1
  • Hitesh Tewari
    • 1
  1. 1.School of Computer Science and StatisticsTrinity College DublinIreland

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