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awarded  Scholar
Nov
22
accepted Efficient set up for a Montgomery multiplication
Nov
14
comment Efficient set up for a Montgomery multiplication
@mikeazo: I said you're correct and also +1'd your comment as it is indeed one way to solve the thing. But you know how it is in today's world: you spare every single bit that you can :D Also, the computation of $R^2 \mod N$ must be performed each time the modulus changes, so depending on the setting, this can happen often and might not be easily precomputed.
Nov
14
revised Efficient set up for a Montgomery multiplication
edited body
Nov
14
comment Efficient set up for a Montgomery multiplication
@mikeazo: This is one way to do it, of course. But it is not efficient as it requires a true multiplication mod $N$ whereas the purpose of Montgomery's multiplication was to be more efficient. Hence, although the cost for it gets lower with the number of Montgomery multiplications performed in this representation, one wants to reduce it if possible.
Nov
14
comment Efficient set up for a Montgomery multiplication
@B-Con: I'd say as much as Montgomery multiplication has: I'm not sure if there are many other settings where one wants to compute modular exponentiations with a modulus of 4096 bits :D
Nov
14
revised Efficient set up for a Montgomery multiplication
added 663 characters in body; edited title
Nov
13
revised What does Maj and Ch mean in SHA-256 algorithm?
typo in title
Nov
13
suggested suggested edit on What does Maj and Ch mean in SHA-256 algorithm?
Nov
13
revised Montgomery Exponentiation - selecting input value R for a given BigInteger
edited tags
Nov
13
asked Efficient set up for a Montgomery multiplication
Nov
9
comment Randomized algorithms and the one time pad
If one think of the key as the whole set of pads, as described above, there is no problem at all provided you always pad the same message with the same pad. (The only problem is that "standard one-time pad" does not really specify what happens when you come to encrypt the same message twice.) The resulting scheme will be semantically secure, assuming the events from your dice are uniformly distributed. (I'm actually thinking of such truly random pads in the example scheme defined above.) Still, the resulting encryption algorithm is fully deterministic (not randomized/probabilistic).
Nov
8
comment Randomized algorithms and the one time pad
@PaŭloEbermann: Indeed, thank you.
Nov
8
revised Randomized algorithms and the one time pad
added 14 characters in body
Nov
8
revised Randomized algorithms and the one time pad
added 9 characters in body
Nov
8
comment Randomized algorithms and the one time pad
@John Deters: You're correct. This is why I stressed that one-time pad does not fit the framework. I'll change the wording accordingly. Thanks.