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comment Designing hash function in space-efficient identity based encryption
@poncho : $\:$ It would probably be important that the sampling of values $\hspace{2 in}$ with a Jacobi symbol of 1 be oblivious. $\;\;\;\;$
Nov
19
comment Availability of a simple limited PRNG algorithm
Yes, there are at least 5 such PRNGs. $\;$
Nov
19
comment DHE key exchange. Is it really secure?
What "prefix" does Alice send to Bob? $\;$
Nov
18
comment What does $\Pi$ represent in cryptography?
It can be "notation for the Encryption scheme in use", but isn't here. $\;$
Nov
18
comment Decrypting A Cipher Text without knowing the key or plaintext
While this link may answer the question, it is better to include the essential parts of the answer here and provide the link for reference. Link-only answers can become invalid if the linked page changes.
Nov
17
comment number theory and cryptographic hardness assumptions
There is no question in your post. $\;$
Nov
17
comment plaintext distribution ,perfect secrecy cryptosystem
However, "a perfect secrecy cryptosystem with specific plaintext probability distribution" would obviously be defined differently. $\;$
Nov
17
comment Secure Multiparty Sum in malicious model using threshold encryption
The NIZK protocols need to be simulation-extractable, rather than just plain NIZK. $\:$ The threshold decryption needs to be simulatable (I don't know whether or not most threshold PKE schemes provide that).
Nov
17
comment fully homomorphic encryption (FHE)
I think this is unusual because, for some circuits $g$, it will require far more homomorphic operations than handling gates with known outputs separately. $\:$ I'm not aware of any non-public-key candidates for FHE. $\;\;\;\;$
Nov
17
comment Show CBC-MAC construction isn't secure
No, it's a proof command. $\;$
Nov
17
comment Collision resistant hash functions
What have you tried? $\;$
Nov
17
comment Show CBC-MAC construction isn't secure
There is no question in your post. $\;$
Nov
17
comment Secure Multiparty Sum in malicious model using threshold encryption
For step 1, you'll need each actor to have it's own NIZK setup string too. $\:$ Step 2 would require a definition of "additive homomorphic encryption" that is far stronger than the usual one, since it would need to handle the fact that the ciphertexts will have been encrypted under different public keys. $\:$ (Are you aware of any candidates for that?) $\;\;\;\;$
Nov
17
comment Secure Multiparty Sum in malicious model using threshold encryption
Does "fully secure" mean secure against stronger adversaries than the $\hspace{2.14 in}$ kind described in your initial paragraph? $\;$
Nov
16
comment fully homomorphic encryption (FHE)
Oh yes, I missed that you were going about it in an unusual way. $\:$ Your suggestion does require that the FHE scheme be public-key, and would need what might be called input-privacy, rather than circuit-privacy.
Nov
16
comment fully homomorphic encryption (FHE)
More generally, $\;\;$ "generates public- and private-key for" $\: \mapsto \:$ "generates a secret key and evaluation key for" $\;\;$ and $\;\;$ "the public key" $\: \mapsto \:$ "the evaluation key" $\;$ .$\;\;\;\;\;\;$ Even for passive adversaries, the FHE scheme would have to have circuit-privacy. $\;\;\;\;\;\;\;\;\;\;\;\;$
Nov
13
comment Verifiable, Distributed Secret Santa Assignments
toc.csail.mit.edu/node/145 $\;$
Nov
10
comment Does the SSH protocol preserve integrity if an endpoint is cloned?
I have no idea. $\;$
Nov
10
comment Does the SSH protocol preserve integrity if an endpoint is cloned?
Would that also cause the "random" bits produced by the clients to be different? $\:$ If yes, $\hspace{.9 in}$ would it cause those to be computationally independent? $\;\;\;\;$
Nov
10
comment Does the SSH protocol preserve integrity if an endpoint is cloned?
Does the cloned clients produce the same "random" bits? $\:$ Can the adversary make the clients send different plaintext to the server despite receiving the exact same communication from the server? $\hspace{.63 in}$