An interactive mutual authentication protocol, which does not allow shared
secrets to pass through untrusted communication media, integrates an
encryption key management system into the authentication protocol. The
server encrypts a particular data random key by first veiling the
particular data random key using a first conversion array seeded by a
shared secret, and then encrypting the veiled particular data random key.
The client decrypts and unveils the particular data random key using the
shared secret, and returns a similarly veiled version of the particular
data random key using a second conversion array seeded by a shared
secret. Access to the shared secret indicates authenticity of the
stations. The procedure may be repeated for a second shared secret for
strong authentication, without allowing shared secrets to pass via
untrusted media.