# partial-domain permutation and strong assumption

Quoting "Verified Security of Redundancy-Free Encryption from Rabin and RSA", Chapter 2 (on page 4):

OAEP was proved IND-CCA-secure by Fujisaki et al. [28] under the assumption that the underlying trapdoor permutation is partial-domain one-way. This is in general a stronger assumption than just one-wayness, but fortunately both assumptions are equivalent in particular for RSA.

• What is exactly are full-domain (and partial-domain) one way permutations?
• Which is the stronger assumption?
• Which is it more secure or efficient?
-
Did you read the cited paper on OAEP? I would expect that it's likely to have a definition of those terms. –  D.W. Nov 7 '13 at 20:25
D.W., by the way, did u refer the original OAEP paper by Bellare&Rogaway? Please be specific, thanks –  habillqabill Nov 12 '13 at 3:47