Massimiliano Sala edited section_Some_cryptographic_applications_This__.tex  about 6 years ago

Commit id: 7d8f836c61525accfd150f4ca775b61534b2370f

deletions | additions      

       

and does not share with anyone,  \item Bob has received $g^a$ and so he can compute another exponentiation $(g^a)^b$ in $Z_p$, the results being $g^{(ab)}$, that he keeps secret  and does not share with anyone,  \item now Alice and Bob have the same value, $g^{(ab)}$, $g^{ab}$,  and they start using it as a key. \end{itemize}  We %  Thanks to the research in finite fields developed in the last $30$ years, we  observe that, even if the enemies simultaneously collect $p$, $g$, $g^a$ and $g^b$, then they have a negligible probability to reconstruct $g^{ab}$ and so the key remains hidden from them.  The system we have described is still used today a lot, especially on the Internet.