Volume 4 - Issue 1
Lattice Based Universal Re-encryption for Mixnet
- Kunwar Singh
National Institute of Technology Tiruchirappalli, India
kunwar@nitt.edu
- C. Pandu Rangan
Indian Institute of Technology Madras Chennai, Tamil Nadu, India
rangan@cse.iitm.ac.in
- A.K.Banerjee
National Institute of Technology Tiruchirappalli, India
banerjee@nitt.edu
Keywords: Lattice, Learning With Error (LWE), Universal Re-encryption
Abstract
Mixnet (Mix Network) was proposed by David Chaum [3] for anonymous communication in 1981.
A mixnet is a multistage system that accepts encrypted messages under the public keys of all intermediate
mixnet nodes and outputs randomly permuted corresponding plaintexts.
In 2004, Golle et al [10] presented a new primitive called universal re-encryption based on the Elgamal
public key cryptosystem. Universal mixnet based on universal re-encryption takes the input
as encrypted messages under the public key of the recipients not the public key of the universal
mixnet so it dispenses with the complexities of the key generation, key distribution and key maintenance.
In Eurocrypt 2010 Gentry, Halevi and Vaikunthanathan [9] presented a cryptosystem which
is an additive homomorphic and a multiplicative homomorphic for only one multiple. In this paper
we present universal re-encryption scheme under learning with error (LWE) assumption based on [9].