  Simple authentication protocols based on conventional physical unclonable
function (PUF) are vulnerable to modeling attacks and other security threats.
This paper proposes an arbiter PUF based on a linear feedback shift register
(LFSR-APUF). Different from the previously reported linear feedback shift
register for challenge extension, the proposed scheme feeds the external random
challenges into the LFSR module to obfuscate the linear mapping relationship
between the challenge and response. It can prevent attackers from obtaining
valid challenge-response pairs (CRPs), increasing its resistance to modeling
attacks significantly. A 64-stage LFSR-APUF has been implemented on a field
programmable gate array (FPGA) board. The experimental results reveal that the
proposed design can effectively resist various modeling attacks such as
logistic regression (LR), evolutionary strategy (ES), Artificial Neuro Network
(ANN), and support vector machine (SVM) with a prediction rate of 51.79% and a
slight effect on the randomness, reliability, and uniqueness. Further, a
lightweight authentication protocol is established based on the proposed
LFSR-APUF. The protocol incorporates a low-overhead, ultra-lightweight, novel
private bit conversion Cover function that is uniquely bound to each device in
the authentication network. A dynamic and timevariant obfuscation scheme in
combination with the proposed LFSR-APUF is implemented in the protocol. The
proposed authentication protocol not only resists spoofing attacks, physical
attacks, and modeling attacks effectively, but also ensures the security of the
entire authentication network by transferring important information in
encrypted form from the server to the database even when the attacker
completely controls the server.
