A comparison between RSA and ElGamal based untraceable blind signature schemes

Abstract

This paper presents a comparison between RSA and ElGamal based untraceable blind signature (BS) schemes through simulation. The objective is to provide a guideline while selecting either of them to develop an application. A BS scheme is a cryptographic protocol that can be used in cryptographic applications like electronic voting systems, electronic payment systems etc to conduct their privacy-related transactions anonymously but securely. While a user operates her electronic transactions employing a BS scheme over the internet, the BS scheme ensures the confidentiality of the secret message of the user. Besides, untraceability is a crucial criterion for any BS scheme because thereby the signer of this scheme is unable to link the message-signature pair after the BS has been revealed to the public. Two untraceable BS schemes: one is proposed by Hwang et al. and is based on RSA cryptosystem whereas the other is proposed by Lee et al. and is based on ElGamal cryptosystem have been chosen here for simulation. The outcome of the simulation model is the comparison of computation time requirement of blinding, singing, unblinding and verification phases of the chosen BS schemes.