Define Undeniable Signature Scheme

Question

Define Undeniable Signature Scheme?

Answer 1

Undeniable signature scheme, introduced by Chaum and van Antwerpen, are non-self-authenticating signature schemes, here signatures can only be confirmed with the signer's consent. Though, when a signature is only demonstrable with the help of a signer, the dishonest signer might refuse to authenticate a genuine document. Undeniable signatures resolve this trouble by adding up a new component termed as the disavowal protocol in adding up to the normal components of verification and signature.