Hot answers tagged

4

Investigate the Paillier cryptosystem for its partially homomorphic properties. The encryption primitive is defined as $E(m)=g^m\cdot r^n \mod n^2$ for a random element $r \in \mathbb{Z}$. From this we can see that given two ciphertexts we have: $$E(m_0)\cdot E(m_1) = (g^{m_0}\cdot {r_0}^n) \cdot (g^{m_1}\cdot {r_1}^n) \mod n^2$$ $$E(m_0)\cdot E(m_1) = g^{...


1

Could you describe the key distribution scheme? If you want symmetric encryption, then your requirement that the intermediaries cannot decrypt anything precludes them all from having the same key, so would it be the case that everyone has a different key, and Bob has all the keys? Or is asymmetric encryption what you had in mind? There is a fundamental ...



Only top voted, non community-wiki answers of a minimum length are eligible