Paper 2011/343

Another Look at Security Definitions

Neal Koblitz and Alfred Menezes


We take a critical look at security models that are often used to give "provable security'' guarantees. We pay particular attention to digital signatures, symmetric-key encryption, and leakage resilience. We find that there has been a surprising amount of uncertainty about what the "right'' definitions might be. Even when definitions have an appealing logical elegance and nicely reflect certain notions of security, they fail to take into account many types of attacks and do not provide a comprehensive model of adversarial behavior.

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ajmeneze @ uwaterloo ca
2012-03-27: last of 4 revisions
2011-06-27: received
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      author = {Neal Koblitz and Alfred Menezes},
      title = {Another Look at Security Definitions},
      howpublished = {Cryptology ePrint Archive, Paper 2011/343},
      year = {2011},
      note = {\url{}},
      url = {}
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