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location Waterloo, Canada
age 29
visits member for 2 years, 5 months
seen Jan 20 '13 at 4:30

I am a PhD student with an interest in theoretical cryptography and mathematical tools used for cryptanalysis.


Mar
10
revised Alternatives to FHE for secure function evaluation
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Mar
10
comment Alternatives to FHE for secure function evaluation
Verifiable homomorphic OT exists, and by the completeness result that existence of secure OT implies existence of secure party computation, I believe we can have verifiability using FHE as well (not sure if composition will work fine or not. As far as I remember, UC model has nothing to say about composobility of homomorphic encryption scheme.) On that note, what is FE?
Mar
10
revised Complexity of arithmetic in a finite field?
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Mar
10
comment Complexity of arithmetic in a finite field?
Oh yes, I should have mentioned that explicitly. I will do it now. Thanks for bringing this to notice.
Mar
10
answered Complexity of arithmetic in a finite field?
Mar
10
comment Alternatives to FHE for secure function evaluation
NIZKP helps in proving to the other party that the gates are constructed properly without any interaction. This will work fine if you are doing SFE because there is no binding on the second party to share the output to the first party. Proactive cryptography works in the scenario where you don't change the shares after some time epoch. It is first studied in the realms of secret sharing, where the first share are formed as in normal SS, but later on, when you need to redistribute the share for same secret, you construct a polynomial with constant 0 and redistribute the share as in normal SS.
Mar
10
revised Alternatives to FHE for secure function evaluation
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Mar
10
comment Alternatives to FHE for secure function evaluation
I will edit my answer appropriately later today to cover these questions as well. They won't fit in one comment space ;) But yes, these are very natural questions. For example, Jarecki and Shmatiko made a garbled circuit secure against active adversary by incorporating that the first party proves in ZK-way the correctness of every gate. Note that in garbled circuit, one party construct the circuit and other computes. It thereby, does not prevent against unfair adversary. Till now, there is no way to get fair computation using Yao's method.
Mar
10
revised Alternatives to FHE for secure function evaluation
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Mar
10
answered Alternatives to FHE for secure function evaluation
Mar
5
comment What is the most practical fully homomorphic cryptosystem?
To add to D.W., the talk given by Halevi is also online on IACR's channel on youtube. It was a very nice talk.
Mar
5
comment What is the flaw in this model for homomorphic encryption?
@mikeazo, I see. I usually jump to the main part of the paper, so missed out the introduction. That was useful information. Thanks!
Mar
5
comment What is the flaw in this model for homomorphic encryption?
@mikeazo, this is public key encryption scheme! I have already this paper. This was the second paper in the line and was later published in EUROCRYPT 2010. The public key is random $x$!
Mar
5
comment What is the flaw in this model for homomorphic encryption?
What I meant to say is that it cannot be a public-key system. Mike, can you please give me the reference as well. I would very much like to read the paper.
Mar
4
answered What is the flaw in this model for homomorphic encryption?
Mar
4
revised Security analysis of a “one-time pad” type hill cipher
Added link and corrected some grammatical errors.
Mar
4
suggested suggested edit on Security analysis of a “one-time pad” type hill cipher
Mar
2
answered In a lattice, how can one define a good basis and a bad basis?
Feb
29
comment Is the $\ell$-Diffie Hellman Inversion easy when g is known?
Thanks for pointing. I corrected the link.
Feb
29
revised Is the $\ell$-Diffie Hellman Inversion easy when g is known?
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