Public Key Cryptography — PKC 2003

Volume 2567 of the series Lecture Notes in Computer Science pp 18-30


An Identity-Based Signature from Gap Diffie-Hellman Groups

  • Jae Cha ChoonAffiliated withDepartment of Mathematics, Korea Advanced Institute of Science and Technology
  • , Jung Hee CheonAffiliated withInformation and Communications University (ICU)


In this paper we propose an identity(ID)-based signature scheme using gap Diffie-Hellman (GDH) groups. Our scheme is proved secure against existential forgery on adaptively chosen message and ID attack under the random oracle model. Using GDH groups obtained from bilinear pairings, as a special case of our scheme, we obtain an ID-based signature scheme that shares the same system parameters with the IDbased encryption scheme (BF-IBE) by Boneh and Franklin [BF01], and is as efficient as the BF-IBE. Combining our signature scheme with the BF-IBE yields a complete solution of an ID-based public key system. It can be an alternative for certificate-based public key infrastructures, especially when efficient key management and moderate security are required.


ID-based signature GDH group Elliptic curve Weil pairing