A Framework for Constructing Convertible Undeniable Signatures.

In this paper, we propose a framework for constructing convertible undeniable signatures from weakly-secure standard signatures. We then present a concrete instantiation employing a standard signature scheme recently proposed at Eurocrypt ΄09. The instantiation is the first (convertible) undeniable signature scheme whose unforgeability relies on the well-known RSA assumption. [ABSTRACT FROM AUTHOR]