Number Of Challenge-response Pairs Research Articles

MLMSA: Multilabel Multiside-Channel-Information Enabled Deep Learning Attacks on APUF Variants

To improve the modeling resilience of silicon strong physical unclonable functions (PUFs), in particular, the APUFs that yield a very large number of challenge response pairs (CRPs), a number of composited APUF variants such as XOR-APUF, interpose-PUF (iPUF), feed-forward APUF (FF-APUF), and OAX-APUF have been devised. When examining their security in terms of modeling resilience, utilizing multiple information sources such as power side channel information (SCI) or/and reliability SCI given a challenge is under-explored, which poses a challenge to their supposed modeling resilience in practice. Building upon multi-label/head deep learning model architecture, this work proposes Multi-Label Multi-Side-channel-information enabled deep learning Attacks (MLMSA) to thoroughly evaluate the modeling resilience of aforementioned APUF variants. Despite its simplicity, MLMSA can successfully break large-scaled APUF variants, which has not previously been achieved. More precisely, the MLMSA breaks 128-stage 30-XOR-APUF, (9,9)-and (2,18)-iPUFs, and (2,2,30)-OAX-APUF when CRPs, power SCI and reliability SCI are concurrently used. It breaks 128-stage 12-XOR-APUF and (2,2,9)-OAX-APUF even when only the easy-to-obtain reliability SCI and CRPs are exploited. The 128-stage six-loop FF-APUF and one-loop 20-XOR-FF-APUF can be broken by simultaneously using reliability SCI and CRPs. All these attacks are normally completed within an hour with a standard personal computer. Therefore, MLMSA is a useful technique for evaluating other existing or any emerging strong PUF designs.

A Physical Unclonable Function Using a Configurable Tristate Hybrid Scheme With Non-Volatile Memory

The physical unclonable function (PUF) is a promising low-cost hardware security primitive. Recent advances in nanotechnology have provided new opportunities for nanoscale PUF circuits. The resistive random access memory (RRAM) is extensively used in nanoscale circuits due to its low cost, non-volatility and easy integration with CMOS. This paper proposes a novel tristate hybrid PUF (TH-PUF) design based on a one-transistor-one-RRAM (1T1R) cell; this cell can be configured into two weak PUFs and a strong PUF using few control signals. To assess the proposed PUF design, a compact RRAM model at UMC 65 nm technology is employed. Simulation results show that the proposed TH-PUF achieves good uniqueness, reliability as well as a higher gate usability compared with an entire CMOS PUFs. The number of challenge response pairs (CRPs) of the proposed TH-PUF is larger than other RRAM-based PUFs. Moreover, the TH-PUF is more resistant to a modeling machine learning attack than traditional PUF designs.

Design, Analysis and Application of Embedded Resistive RAM Based Strong Arbiter PUF

Resistive Random Access Memory (RRAM) based Physical Unclonable Function (PUF) designs exploit either the probabilistic switching or the resistance variability during forming, SET and RESET processes of RRAM. Memory PUFs using RRAM are typically weak PUFs due to fewer number of challenge response pairs. We propose a strong arbiter PUF based on 1T-1R bit cell which is designed from conventional RRAM memory array with minimally invasive changes. Conventional voltage sense amplifier is repurposed to act like an arbiter and generate the response. Similarly, address and data lines are repurposed to act as challenge and response bits respectively. The PUF is simulated using 65 nm predictive technology models for CMOS and Verilog-A model for a hafnium oxide based RRAM. The proposed PUF architecture is evaluated for uniqueness, uniformity and reliability for various number of stages. It demonstrates mean intra-die Hamming Distance (HD) of 0.135 percent and inter-die HD of 51.4 percent, and passes the NIST tests. We study the vulnerability of proposed PUF to machine learning attacks. We also present an application of proposed PUF for data attestation in the internet of things. Proposed PUF-based data attestation consumes 9.88pJ of total energy per data block of 64-bits and offers a speed of 120.7 kbps.

Set-Based Obfuscation for Strong PUFs Against Machine Learning Attacks

Strong physical unclonable function (PUF) is a promising solution for device authentication in resource-constrained applications but vulnerable to machine learning (ML) attacks. In order to resist attack, many defenses have been proposed in recent years. However, these defenses incur high hardware overhead, degenerate reliability and are inefficient against advanced ML attacks such as approximation attacks. To address these issues, we propose a Random Set-based Obfuscation (RSO) for Strong PUFs to resist ML attacks. The basic idea is that several stable responses are derived from the PUF itself and pre-stored as the set for obfuscation in the testing phase, and then a true random number generator is used to select any two keys to obfuscate challenges and responses with XOR operations. When the number of challenge-response pairs (CRPs) collected by the attacker exceeds the given threshold, the set will be updated immediately. In this way, ML attacks can be prevented with extremely low hardware overhead. Experimental results show that for a 64 × 64 Arbiter PUF, when the size of set is 32 and even if 1 million CRPs are collected by attackers, the prediction accuracies of the several ML attacks we use are about 50% which is equivalent to the random guessing.

A Highly Reliable Strong Physical Unclonable Function Design Based on FPGA

Physical unclonable function (PUF) generates unique secret keys from unavoidable IC manufacturing variations, which can eliminate high computation expense and additional key storage. The inherent flexibility and lower time-to-market have made field programmable gate array (FPGA) the platform of choice for faster implementation. However, logic elements on FPGA are predefined while some types of PUFs need strictly mirrored symmetric routing. This paper presents a robust and FPGA friendly PUF based on oscillator collapse (OC-PUF) with million number of challenge-response pairs (CRPs). Mirrored routes are obtained with a novel delay cell design and a signal path configuration technique. In the meanwhile, the response bias issues on FPGA is effectively resolved. Measured on Altera DE2-115, the average interchip hamming distance (inter-chip HD) of the proposed OC-PUF is 46.7%. After applying dynamic threshold with a value 255, intra-chip hamming distance (intra-chip HD) dropped to 5.46E-06 at nominal conditions.

Design of Robust, High-Entropy Strong PUFs via Weightless Neural Network

Physically unclonable functions (PUFs) have been explored as lightweight hardware primitives for the purpose of realizing robust security via strong authentication or secure key/ID generation. PUF harness manufacturing process variations for the purpose of generating binary keys or binary functions. An ideal strong PUF is a binary function that maps an m-bit input challenge to an uniquen-bit output response, making it attractive for authentication applications. Unfortunately, real strong PUF implementations suffer from reliability issues where the same challenge may produce different responses in the presence of noise. To overcome this problem, strong PUF leverages the availability of exponential number of challenge-response pairs (CRPs). A successful authentication event requires acquiring multiple CRPs and applying a threshold. In contrast, weak PUFs produce limited keys and are required to be highly reliable. Multiple techniques have been developed to achieve the necessary reliability. An additional prerequisite for strong PUFs is resilience against model-building attacks (cloning) by an adversary, who has observed a few CRPs, to prevent successful prediction of future CRPs. In this work, we first illustrate a strong PUF design that re-purposes a weightless neural network (WNN). Second, we showcase the robustness of WNN-based strong PUFs with respect to machine learning attacks, while providing desirable uniqueness and reliability metrics. Finally, we employ an initial entropy source of highly reliable weak PUF bits mapped to weightless neural networks (WNNs) for the purpose of creating a near-ideal strong PUF in terms of reliability. Our results show that it is possible to create highly reliable WNN–based strong PUFs with < 65 % ML accuracy by using as few as 32 initial reliable weak PUF bits.

Defense Mechanisms against Machine Learning Modeling Attacks on Strong Physical Unclonable Functions for IOT Authentication: A Review

Security component in IoT system are very crucial because the devices within the IoT system are exposed to numerous malicious attacks. Typical security components in IoT system performs authentication, authorization, message and content integrity check. Regarding authentication, it is normally performed using classical authentication scheme using crypto module. However, the utilization of the crypto module in IoT authentication is not feasible because of the distributed nature of the IoT system which complicates the message cipher and decipher process. Thus, the Physical Unclonable Function (PUF) is suggested to replace crypto module for IoT authentication because it only utilizes responses from set of challenges instead of cryptographic keys to authenticate devices. PUF can generate large number of challenge-response pairs (CRPs) which is good for authentication because the unpredictability is high. However, with the emergence of machine learning modeling, the CRPs now can be predicted through machine learning algorithms. Various defense mechanisms were proposed to counter machine learning modeling attacks (ML-MA). Although they were experimentally proven to be able to increase resiliency against ML-MA, they caused the generated responses to be instable and incurred high area overhead. Thus, there is a need to design the best defense mechanism which is not only resistant to ML-MA but also produces reliable responses and reduces area overhead. This paper presents an analysis on defense mechanisms against ML-MA on strong PUFs for IoT authentication.