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Apr
12
comment security in the standard model → random oracle model?
Thanks for your answer. I've not really understood.
Apr
11
asked security in the standard model → random oracle model?
Mar
28
comment Times of nested algorithms in proofs of security
If there are oracles calls and responses then there is interaction... I've understood the following: we assume that $A$ does not make any difference between the simulated oracles and conventional ones (not simulated). Consequently, we have to consider that the interactions are instant.
Mar
28
accepted Times of nested algorithms in proofs of security
Mar
28
comment Times of nested algorithms in proofs of security
Thank you for all your explanations DrLecter.
Mar
28
comment Times of nested algorithms in proofs of security
DrLecter, my previous comment is right ?
Mar
28
comment Times of nested algorithms in proofs of security
Thanks DrLecter, so, when you say that oracle queries costs $1$ you speak of simulated oracle, and real oracle queries (for instance when $A'$ uses itself an oracle) costs "nothing". That's right ?
Mar
28
comment Times of nested algorithms in proofs of security
I make the distinction between simulated oracle and "real" oracle. I thought in your explanation that "real" oracle queries costs $1$ whereas "simulated" oracle costs the time to make the needed computations.
Mar
28
comment Times of nested algorithms in proofs of security
Sorry I've read "subalgorithms" of $A$ in your answer. In fact I've already understood your comments. There is only small details that are a problem for me. You say that oracle queries costs $1$ unit of time. Why they don't appear in the times of proofs by reduction ? It seems to me that if we have $q$ oracle calls, we should take into account the amount of time $q$, not ?
Mar
28
comment Times of nested algorithms in proofs of security
Thank you for your efforts to explain me. Why you say that the "subalgorithms" of A simulate the challenger and the oracles ? This is not $A'$ (t.i.t.s. the reduction) which simulates the environment of $A$ ?
Mar
28
comment Times of nested algorithms in proofs of security
Thanks @tylo. I perfectly understand that the time of $A'$ is at least the time of $A$, but why can we deduct the time of $A$ ? Since at each query/response, when $A$ is waiting (and is making computations during this waiting) for the response from $A'$, time is elapsing for both...
Mar
27
comment Times of nested algorithms in proofs of security
Thank you very much DrLecter.
Mar
27
comment Times of nested algorithms in proofs of security
Thanks DRLecter, "\textbf{yes}, but A has to do something and not only make oracle calls to be successful". In fact the subject of my question was why we can remove the time to performs the set of queries (namely $n \cdot t_c$). Thanks for the paper.
Mar
27
comment Times of nested algorithms in proofs of security
Thank DrLecter. If you set to $0$ the communication times in my example there is always a problem... Imagines that $A$ makes a query ($0$ unit of times), $A'$ receives the query and performs a computation ($1$ unit of time) and responds to $A$ ($0$ unit of time). For $A$ as well as for $A'$, the amount of time elapsed is $1$. Not ?
Mar
27
comment Times of nested algorithms in proofs of security
When I say that I don't understand why "there is a "pause" (in the elapsed time for A) when A is waiting for the response to a query", I'm speaking about a simulated oracle since this is $A'$ which responds to $A$.
Mar
27
comment Times of nested algorithms in proofs of security
Thanks DrLecter. An oracle call requires (or doesn't require ?) unit time ? What is referred to the simulation of an oracle call ? I don't understand what this means.
Mar
27
comment Times of nested algorithms in proofs of security
Even if $A'$ makes more computation after having obtained the output from $A$ this does not explain why there is a "pause" (in the elapsed time for $A$) when $A$ is waiting for the response to a query !
Mar
27
comment Times of nested algorithms in proofs of security
@DrLecter Yes I've supposed that $A'$ doesn't need more computations at the end so as to show what is the problem.
Mar
27
revised Times of nested algorithms in proofs of security
added 160 characters in body
Mar
27
comment Times of nested algorithms in proofs of security
Thanks tylo, I've not understood your last comment because of mistakes when writing... And this is not clear because when $A$ waits for the responses from $A'$, time is always elapsing. Even is $A$ is a standalone algorithm, each waiting takes time...