A Novel Multi-factor ID-based Designated Verifier Signature scheme

In a classic digital signature scheme, the global community is capable of verifying a signature. In a designated verifier scheme (DVS), only the designated verifier has this capability. In a classic DVS scheme the signer themselves “designates” the entity that will have the capability of verifying their signature. In a pure identity-based signature scheme a Trusted Authority is introduced, and is responsible for issuing secret signing keys to all participants. In our proposed scheme it is this TA, not the signer, that designates the verifier, and to this end the TA issues the designated verifier with its own secret. Finally we propose a variation that supports non-repudiation, plus a multi-factor signature capability.