  There has been a growing interest in fully integrating Physical Unclonable
Function (PUF) for cryptographic primitives, or keyless encryption. Keyless
primitives do not store key information during the entire encryption and
decryption phase, providing full security against volatile and non-volatile
memory attacks. The concept of keyless encryption using ReRAM PUF is a
relatively new concept, and the security aspect of the protocol has not been
tested yet. In this paper, we use statistical models to analyze the randomness
of the protocol and its resistance against frequency attacks.
