Diffie-Hellman Public-key distribution scheme Cannot be used to exchange an arbitrary message Exchange only a key, whose value depends on the participants(and their private and public key information) The algorithm is based on exponentiation in a finite(Galois)field, either over integers modulo a prime, or a polynomial field4 Diffie-Hellman • Public-key distribution scheme • Cannot be used to exchange an arbitrary message • Exchange only a key, whose value depends on the participants (and their private and public key information) • The algorithm is based on exponentiation in a finite (Galois) field, either over integers modulo a prime, or a polynomial field