Abstract: We compare the relative strengths of popular notions of security for public key encryption schemes. We consider the goals of indistinguishability and non-malleability, each under chosen plaintext attack and two kinds of chosen ciphertext attack. For each of the resulting pairs of definitions we prove either an implication (every scheme meeting one notion must meet the other) or a separation (there is a scheme meeting one notion but not the other, assuming the first notion can be met at all). We similarly treat plaintext awareness, a notion of security in the random oracle model. An additional contribution of this paper is a new definition of non-malleability which we believe is simpler than the previous one.
Ref: Extended abstract in Advances in Cryptology - Crypto 98 Proceedings, Lecture Notes in Computer Science Vol. 1462, H. Krawczyk ed, Springer-Verlag, 1998. Full paper available below.
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