An efficient protocol for anonymous fingerprinting

We propose a new anonymous fingerprinting scheme using Okamoto-Uchiyama cryptosystem[1]. In the previous schemes[2]-[4] Pfitzmann et al. applies bit commitment schemes, but they are not practical as the enciphering rate is extremely low. In order to improve the rate, we have applied the Okamoto-Uchiyama cryptosystem which homomorphic property makes it possible to embed an encrypted fingerprint in an encrypted digital contents. Exploiting the property ingenuously, we can achieve the same enciphering rate as that of Okamoto-Uchiyama cryptosystem in theory. The security can also be protected for both of a buyer and a merchant in our scheme.