Maeher
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 Jul 13 comment pairing-based schemes Well scalar multiplication does not have bilinearity, a pairing does. Jul 2 reviewed Approve How do I choose the best 3*3 s-boxes? Jun 24 comment Is there a way to compress multiple signatures of the same data? Aggregate Signatures are more general than that, but might offer you what you want. Jun 21 reviewed Approve How to calculate inverse affine transform in AES from forward affine transform? Jun 21 reviewed Approve Is there a malleable pubkey digital signature scheme? Jun 21 reviewed Approve Hill cipher key space Jun 21 reviewed Approve Unblind a RSA blinded signature Jun 12 reviewed Approve How realistic is a dictionary attack on a secure remote password protocol (SRP) verifier? May 29 reviewed Approve Encryption time in ECC May 28 reviewed Approve how much trust can we place in protocol verifiers? May 22 comment One-time pad, zero key and Shannon By "using Shannon" you mean applying Shannon's theorem? Sure, you can define your key-generation algorithm to pick the all zero key with probability 0 and all others with probability $1/(|\mathcal{M}|-1)$. That's exactly your encryption scheme. Then apply the theorem which states that the scheme is perfectly secret if and only if two condition hold. One of those conditions is that every key is chosen with the same probability, which obviously does not hold. May 22 comment One-time pad, zero key and Shannon @CGFoX Well, we are talking about the OTP here (except that the all zero key is not allowed), so by definition, $\mathcal{M}=\mathcal{C}=\{0,1\}^n$. But even if they are some other sets. If the set of keys has an element less that the messages, then for any ciphertext $c$, there exists at least one message $m$ that cannot possibly result in $c$ no matter which key is chosen. May 21 reviewed Reject Shamir Secret sharing - Can share generator keep x values secret? May 21 reviewed Reject Shamir Secret sharing - Can share generator keep x values secret? May 21 revised One-time pad, zero key and Shannon Added a bit more explanation, why this is a valid argument. May 21 answered One-time pad, zero key and Shannon May 21 comment Which concrete applications benefit from Oblivious RAM constructions? @e-sushi I don't quite get what your comment is trying to convey. He is NOT asking about attacks on ORAM (this is indeed a much used abbreviation). He is asking about the attacks on non oblivious encrypted data-structures that are the motivation to develop ORAM construction (be that Hash based or whatever) May 21 reviewed Close encryption and decryption time for RSA-crt in java? May 21 comment Prefix property for variable length pseudo-random generators $m_0$ and $m_1$ certainly still have to have the same length. Check Definition 3.8. With messages of different length, the security definition becomes meaningless. May 15 reviewed Reject Is it possible to construct a secure block cipher of size $2n$ given a secure block cipher of size $n$?