An improved universal re-encryption based on okamoto-uchiyama cryptosystem
Nazmul Islam, Kazi Md. Rokibul Alam, Yasuhiko Morimoto · 2016
Universal re-encryption technique is an important tool that enables an intermediary to re-encrypt a ciphertext without any knowledge of corresponding public key. This technique, as shown by Golle et. al., conventionally utilizes ElGamal cryptosystem for its operations and generates two pairs of ciphertexts. With ElGamal cryptosystem, efficiency of this technique decreases as resources in terms of time and memory are consumed significantly by the amount of generated ciphertexts. The purpose of the paper is to increase the efficiency of universal re-encryption technique by reducing the ciphertext quantity and to make the technique suitable for resource constraint devices while keeping the facilities of conventional universal re-encryption technique in full concern. To show the effectiveness of proposed technique, this paper includes an analysis on experimental data from the simulation of mix-networks.