Certificateless Partially Blind Signature

Blind signatures play a central role in applications such as e-cash and e-voting systems, while partially blind signature is an even more applicable variant. This paper proposes a Certificate less Partially Blind Signature (CPBS) by laying its construction on bilinear pairings over Gap Diffie-Hellman (GDH) Group for solving the key escrow problem in normal ID-based partially blind signature. Formally, a framework is presented for defining the components of CPBS scheme and illustrating attack models. We then prove that our new scheme is secure in the random oracle model if we assume that Computational Diffie-Hellman Problem (CDHP) is intractable. Also, we theoretically validate that our proposed scheme is more efficient than those existing ones in terms of computational complexity.