Patent ID: 7356140
Filing Date: 2008-04-08
Classification: H04L

Abstract:
1. An encrypting device comprising: key generation means for generating two prime numbers p and q of which product is n=pq as a private key and generating as a public key g1 and g2 respectively given by the following Equations (1) and (2) using two random numbers s and t and a maximal generator g in a multiplicative group of integers modulo n; and encrypting arithmetic means for, in response to receipt of a plaintext m, generating a ciphertext C=(C1, C2) respectively given by the following Equations (3) and (4) using the public key {g1, g2}, a private key n, and random numbers r1 and r2, where gcd{s, q−1}=1 and gcd{t, p−1}=1.