National Chung Hsing University
Public key cryptosystem was an epoch-creating approach of research in the last few decades, and it is still drawing hundreds and thousands of researcher's attention now. In such a cryptosystem, each valid user has a public key and a private key. One can either encrypt the content of the message with the receiver s public key or sign it with one's own private key to prove the validity of the access to the message. Recently, Hwang et al. proposed a simple batch verifying multiple RSA digital signatures. Their scheme is efficient to reduce computation of verifying multiple RSA signatures. In this paper, the authors propose a cryptanalysis and improvement of their scheme.