Chapter

Advances in Cryptology - EUROCRYPT 2004

Volume 3027 of the series Lecture Notes in Computer Science pp 56-73

Short Signatures Without Random Oracles

  • Dan BonehAffiliated withComputer Science Department, Stanford University
  • , Xavier BoyenAffiliated withVoltage Security

Abstract

We describe a short signature scheme which is existentially unforgeable under a chosen message attack without using random oracles. The security of our scheme depends on a new complexity assumption we call the Strong Diffie-Hellman assumption. This assumption has similar properties to the Strong RSA assumption, hence the name. Strong RSA was previously used to construct signature schemes without random oracles. However, signatures generated by our scheme are much shorter and simpler than signatures from schemes based on Strong RSA. Furthermore, our scheme provides a limited form of message recovery.