Perfectly Secure Oblivious RAM without Random Oracles

  • Ivan Damgård
  • Sigurd Meldgaard
  • Jesper Buus Nielsen
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6597)


We present an algorithm for implementing a secure oblivious RAM where the access pattern is perfectly hidden in the information theoretic sense, without assuming that the CPU has access to a random oracle. In addition we prove a lower bound on the amount of randomness needed for implementing an information theoretically secure oblivious RAM.


Access Pattern Random Oracle Bottom Level Read Operation Physical Memory 
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Copyright information

© International Association for Cryptologic Research 2011

Authors and Affiliations

  • Ivan Damgård
    • 1
  • Sigurd Meldgaard
    • 1
  • Jesper Buus Nielsen
    • 1
  1. 1.Department of Computer ScienceAarhus UniversityDenmark

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