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### Proving 2-way nesting security

I recently came across the theorem about $n$-way nesting. It states that if $\mathcal{E}=(E, D)$ is semantically secure, then $\mathcal{E}$ is secure for $n$-way nesting. I'm trying to prove the ...
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### Reduction from Distinguisher to Indishtinguishability

Content and Informal Problem Suppose a protocol $\pi$ doing an arbitrary task between two users A and B. I only know that $\pi$ relies on a IND-CPA symmetric encryption scheme $\mathcal{E} =$(KeyGen, ...
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### Computing the advantage when checking PRF

I am reading a pdf on pseudorandom function I found here https://www.cs.utexas.edu/~dwu4/courses/sp21/static/reductions.pdf My problem/struggle is with the computation of the distinguisher's $B$ ...
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Given a polynomial-time adversary $A$ with binary output, the distinguishing advantage of $A$ with respect two games $G, H$ is defined as  \newcommand{\adv}{\mathbf{Adv}} \newcommand{\pr}{\mathbf{Pr}...
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### How to understand the "Authenticity" and "Privacy" of CCM-mode encryption scheme?

CCM mode refers to CTR+ CBC-MAC encryption mode. Based on this paper, the adversary's advantages against the authenticity of CCM is: Eq(1) Authenticity: it should be infeasible for an adversary to ...
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### What is the definition of semantic secure advantage?

I'm doing sequence-of-game formal security analysis for key exchange protocol. It confuses me a lot how to calculate the adversary's semantic secure (SS) advantage. In Shoup's tutorial "sequences ...
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### A smaller modulus-to-noise ratio means more security in LWE

Let $\text{Adv}^{\text{DLWE}}_{n,m,q,\sigma}$ be the advantage of an attacker to distinguish LWE samples from uniform ones, where $m$ is the number of samples, $q$ the modulus and $\sigma$ the ...
The Cryptography made simple (page 207, under Fig 11.12)(Nigel Smart) say that adversary's advantage of IND-PASS Game is $Adv1 = 2\times|Pr[b=b']-\frac{1}{2}|$. The reason for multiplying by 2 is to ...