A short ID‐based proxy signature scheme
Maryam Rajabzadeh Asaar, Mahmoud Salmasizadeh, Willy Susilo · International Journal of Communication Systems · 2014
Summary The notion of identity‐based proxy signature with message recovery feature has been proposed to shorten identity‐based proxy signatures and improve their communication overhead because signed messages are not transmitted with these kinds of signatures. There are a few schemes for this notion: the schemes of Singh and Verma and Yoonet al. Unfortunately, Tianet al., by presenting two forgery attacks, show that Singh and Verma scheme is not secure, and also, the scheme of Yoonet al. does not support provable security. The contributions of this paper are twofold. First, we review the scheme by Yoonet al.and discuss why it does not have message recovery property, and consequently, it is not short. Second, we propose a short identity‐based proxy signature scheme with the help of message recovery property and show that it is secure under computational Diffie–Hellman assumption in the random oracle model. Furthermore, our scheme is more efficient than (as efficient as) previous identity‐based proxy signatures. Copyright © 2014 John Wiley & Sons, Ltd.