The certificateless-based signature system allows people
to verify the signature without the certificate. For this
reason, we do not need the certificate authority (CA)
to store and manage users’ certificates and public keys.
Certificateless-based signature can also overcome the certificate
management problem and the key escrow problem
of the traditional signature system. In 2012, Zhang
and Mao first designed the certificateless-based signature
scheme based on RSA operations; however, their scheme
still has latent vulnerabilities. To overcome these shortcomings,
we propose an improved version to make the
RSA-based certificateless scheme stronger and more secure.
Besides, we reduce the computational cost to make
our scheme more efficient.