7 research outputs found
ПРИМЕНЕНИЕ КОНФИГУРИРУЕМЫХ ГЕНЕРАТОРОВ ИМПУЛЬСОВ ДЛЯ ИДЕНТИФИКАЦИИ ПЛИС
Рассматривается возможность применения конфигурируемых генераторов цифровых импульсов в качестве аппаратной реализации физически неклонируемых функций для решения задачидентификации программируемых логических интегральных схем (ПЛИС) типа FPGA. Приводятся и анализируются результаты экспериментальных исследований генераторов импульсов, реализованных для FPGA Xilinx SPARTAN-3E
A Physical Unclonable Function Based on Inter-Metal Layer Resistance Variations and an Evaluation of its Temperature and Voltage Stability
Keying material for encryption is stored as digital bistrings in non-volatile memory (NVM) on FPGAs and ASICs in current technologies. However, secrets stored this way are not secure against a determined adversary, who can use probing attacks to steal the secret. Physical Unclonable functions (PUFs) have emerged as an alternative. PUFs leverage random manufacturing variations as the source of entropy for generating random bitstrings, and incorporate an on-chip infrastructure for measuring and digitizing the corresponding variations in key electrical parameters, such as delay or voltage. PUFs are designed to reproduce a bitstring on demand and therefore eliminate the need for on-chip storage. In this dissertation, I propose a kind of PUF that measures resistance variations in inter-metal layers that define the power grid of the chip and evaluate its temperature and voltage stability. First, I introduce two implementations of a power grid-based PUF (PG-PUF). Then, I analyze the quality of bit strings generated without considering environmental variations from the PG-PUFs that leverage resistance variations in: 1) the power grid metal wires in 60 copies of a 90 nm chip and 2) in the power grid metal wires of 58 copies of a 65 nm chip. Next, I carry out a series of experiments in a set of 63 chips in IBM\u27s 90 nm technology at 9 TV corners, i.e., over all combination of 3 temperatures: -40oC, 25oC and 85oC and 3 voltages: nominal and +/-10% of the nominal supply voltage. The randomness, uniqueness and stability characteristics of bitstrings generated from PG-PUFs are evaluated. The stability of the PG-PUF and an on-chip voltage-to-digital (VDC) are also evaluated at 9 temperature-voltage corners. I introduce several techniques that have not been previously described, including a mechanism to eliminate voltage trends or \u27bias\u27 in the power grid voltage measurements, as well as a voltage threshold, Triple-Module-Redundancy (TMR) and majority voting scheme to identify and exclude unstable bits
An FPGA Chip Identification Generator Using Configurable Ring Oscillator
Abstract—An improved chip identification (ID) generator, otherwise known as a physically unclonable function (PUF) is described. Similar to previous designs, a cell, i, is used to obtain a measure of the difference in period of four ring oscillators and obtain the residue Ri, a random variable. Experiments show it is normally distributed with a mean of 0. A binary output value of 0 or 1 assigned depending on the sign of Ri. When |E(Ri) | is large, this scheme consistently gives the same output. Unfortunately, when it is small, the repeatability is compromised, particularly when variations in operating conditions such as supply voltage and temperature are also taken into account, which is a common problem for all previous works. To address this problem, we propose a cell with configurable ring oscillators together with an orthogonal re-initialisation scheme. Together, these two techniques maximise repeatability by causing the distribution of the mean of different Ri’s to change from normal to bimodal. We implement this design in the Xilinx Spartan-3e FPGA. Nine FPGA chips are tested, and experimental results show that the new method significantly enhances reliability of ID generation and tolerance to environmental changes. Bit flip rate is reduced from 1.5 % to approximately 0 at a fixed supply voltage and room temperature. Over the 20 − 80 ◦ C temperature range, and a 25 % variation in supply voltage, the bit flip rate is reduced from 1.56 % to 3.125 × 10 −7, which is a 50000 × improvement. I
Design of hardware-orientated security towards trusted electronics.
While the Internet of Things (IoT) becomes one of the critical components in the
cyber-physical system of industry 4.0, its root of trust still lacks consideration. The
purpose of this thesis was to increase the root of trust in electronic devices by
enhance the reliability, testability, and security of the bottom layer of the IoT
system, which is the Very Large-Scale Integration (VLSI) device. This was
achieved by implement a new class of security primitive to secure the IJTAG
network as an access point for testing and programming. The proposed security
primitive expands the properties of a Physically Unclonable Function (PUF) to
generate two different responses from a single challenge. The development of
such feature was done using the ring counter circuit as the source of randomness
of the PUF to increase the efficiency of the proposed PUF. The efficiency of the
newly developed PUF was measured by comparing its properties with the
properties of a legacy PUF. The randomness test done for the PUF shows that it
has a limitation when implemented in sub-nm devices. However, when it was
implemented in current 28nm silicon technology, it increases the sensitivity of the
PUF as a sensor to detect malicious modification to the FPGA configuration file.
Moreover, the efficiency of the developed bimodal PUF increases by 20.4%
compared to the legacy PUF. This shows that the proposed security primitive
proves to be more dependable and trustworthy than the previously proposed
approach.Samie, Mohammad (Associate)PhD in Transport System