SDVS Sender-Privacy in the Multi-party Setting

Strong designated verifier signature schemes rely on sender-privacy to hide the identity of the creator of a signature to all but the intended recipient. This property can be invaluable in, for example, the context of deniability, where the identity of a party should not be deducible from the communication sent during a protocol execution. In this work, we explore the technical definition of sender-privacy and extend it from a 2-party setting to an n-party setting. Afterwards, we show in which cases this extension provides stronger security and in which cases it does not.