fmouhart/thesis
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Reduction DDH => DLP

Browse Source
This commit is contained in:
Fabrice Mouhartem 2018-02-06 09:25:41 +01:00
parent b7cbdeb662
commit 0d2d8d934f
1 changed files with 5 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
chap-proofs.tex
View File

@ -129,7 +129,11 @@ To illustrate this, let us consider the two following assumptions:
The \textit{\DDH assumption} is the intractability of the problem for any $\ppt$ algorithm.
\end{definition}
The discrete logarithm assumption is implied by the decisional Diffie-Hellman assumption for instance. Indeed, if we can solve the discrete logarithm problem, then it suffices to compute the discrete logarithm of $g_1$, let say $a$, and then check whether $g_2^a = g_3$. Thus it is preferable to work with the discrete logarithm problem if it is possible.
The discrete logarithm assumption is implied by the decisional Diffie-Hellman assumption for instance.
Indeed, if one is able to solve the discrete logarithm problem, then it suffices to compute the discrete logarithm of $g_1$, let say $\alpha$, and then check whether $g_2^\alpha = g_3$.
This is why it is preferable to work with the discrete logarithm assumption if it is possible.
For instance, there is no security proofs for the El Gamal encryption scheme from DLP.
\section{Random-Oracle Model, Standard Model and Half-Simulatability}