A practical convertible quantum signature scheme with public verifiability into universal quantum designated verifier signature using self-certified public keys

Efficient digital signatures ensure the integrity, authenticity and non-repudiation of the data. A quantum signature scheme with a public verifier is one of the schemes that use the verifier publicly for verification and use the conversion of the quantum signature with the public verifier into a designated verifier via the aid of a semi-trusted party for designing the keys for the users. The proposed scheme provides a secure quantum signature, which is beneficial in addressing the issues relating to the privacy of online bidding, electronic voting and electronic payment. Moreover, the public-key cryptosystem makes it easier to implement and secure against quantum attacks as compared to the other quantum signature schemes.