A Lightweight and Practical Anonymous Authentication Protocol Based on Bit-Self-Test PUF

Physical unclonable function (PUF), a cryptographic primitive, has recently been used in protocol design because it can ensure a tamper-evident feature. In many PUF-based protocol schemes, helper data algorithms (HDA) or fuzzy extractors (FE) are used to generate strong keys from unreliable PUF responses. However, these methods inevitably introduce complex error correction techniques, which not only increase the overhead of embedded devices but also pose some security risks. We propose a novel HDA technology, which does not use any high-overhead error correction mechanism, greatly reducing the implementation complexity and execution overhead. The novel HDA exploits the strategy of bit-self-test (BST) and the PUF can extract the robust responses by using the real-time generated reliable flags, and then an entropy extractor is used to generate the reliable and random key with high entropy. Based on this novel HDA, we design a lightweight anonymous authentication protocol. The protocol uses pseudo-random function (PRF) and XOR operation instead of the traditional hash function and symmetric encryption algorithm, which ensures security while reducing the overhead. Moreover, the proposed protocol does not require the server to store a large number of challenge–response pairs (CRPs), which reduces the storage overhead on the server while avoiding the risk of leakage of CRPs. Moreover, the device identity ID is updated during each round of the authentication process, which prevents the device from being tracked and protects the privacy of the device. The implementation and performance analysis of the protocol prototype on a Zynq-7000 SoC XC7Z010 FPGA shows that the proposed scheme solves the problems encountered with existing schemes and has additional security properties

BFWindow: Speculatively Checking Data Property Consistency against Buffer Overflow Attacks

Buffer overflow is one of the main approaches to get control of vulnerable programs. This paper presents a protection technique called BFWindow for performance and resource sensitive embedded systems. By coloring data structure in memory with single associate property bit to each byte and extending the target memory block to a BFWindow(2), it validates each memory write by speculatively checking consistency of data properties within the extended buffer window. Property bits are generated by compiler statically and checked by hardware at runtime. They are transparent to users. Experimental results show that the proposed mechanism is effective to prevent sequential memory writes from crossing buffer boundaries which is the common scenario of buffer overflow exploitations. The performance overhead for practical protection mode across embedded system benchmarks is under 1%.SCI(E)[email protected]; [email protected]

A Lightweight and Practical Anonymous Authentication Protocol Based on Bit-Self-Test PUF

Physical unclonable function (PUF), a cryptographic primitive, has recently been used in protocol design because it can ensure a tamper-evident feature. In many PUF-based protocol schemes, helper data algorithms (HDA) or fuzzy extractors (FE) are used to generate strong keys from unreliable PUF responses. However, these methods inevitably introduce complex error correction techniques, which not only increase the overhead of embedded devices but also pose some security risks. We propose a novel HDA technology, which does not use any high-overhead error correction mechanism, greatly reducing the implementation complexity and execution overhead. The novel HDA exploits the strategy of bit-self-test (BST) and the PUF can extract the robust responses by using the real-time generated reliable flags, and then an entropy extractor is used to generate the reliable and random key with high entropy. Based on this novel HDA, we design a lightweight anonymous authentication protocol. The protocol uses pseudo-random function (PRF) and XOR operation instead of the traditional hash function and symmetric encryption algorithm, which ensures security while reducing the overhead. Moreover, the proposed protocol does not require the server to store a large number of challenge–response pairs (CRPs), which reduces the storage overhead on the server while avoiding the risk of leakage of CRPs. Moreover, the device identity ID is updated during each round of the authentication process, which prevents the device from being tracked and protects the privacy of the device. The implementation and performance analysis of the protocol prototype on a Zynq-7000 SoC XC7Z010 FPGA shows that the proposed scheme solves the problems encountered with existing schemes and has additional security properties

A Belief Coulomb Force in D-S Evidence Theory

Dempster-Shafer (D-S) evidence theory is regarded as an effective method of dealing with the uncertainty of the information but still suffers from the conflict problem among the evidence. Despite that various techniques were presented in plenty of publications, currently, there is no convincing evidence and firm conclusion about the optimum solution. This study presents Belief Coulomb Force (BCF) into D-S evidence theory, where Zhou et al. entropy is applied to represent the electrical charge of the belief function, and the Coulomb gravity or repulsion would be identified with the Pearson correlation coefficient. According to the simulation results, the recognition accuracy on malfunction diagnosis of the presented approach reaches 93.7%, and the effectiveness of analyzing the conflict evidence problem can be demonstrated from the comparison with the previous methods

SO2 over Central China: Measurements, Numerical Simulations and the Tropospheric Sulfur Budget

SO2 in central China was measured in situ from an aircraft and remotely using the Ozone Monitoring Instrument (OMI) from the Aura satellite; results were used to develop a numerical tool for evaluating the tropospheric sulfur budget - sources, sinks, transformation and transport. In April 2008, measured ambient SO2 concentrations decreased from approx.7 ppbv near the surface to approx. 1 ppbv at 1800 m altitude (an effective scale height of approx.800 m), but distinct SO2 plumes were observed between 1800 and 4500 m, the aircraft's ceiling. These free tropospheric plumes play a major role in the export of SO2 and in the accuracy of OMI retrievals. The mean SO2 column contents from aircraft measurements (0.73 DU, Dobson Units) and operational OMI SO2 products (0.63+/-0.26 DU) were close. The OMI retrievals were well correlated with in situ measurements (r = 0.84), but showed low bias (slope = 0.54). A new OMI retrieval algorithm was tested and showed improved agreement and bias (r = 0.87, slope = 0.86). The Community Multiscale Air Quality (CMAQ) model was used to simulate sulfur chemistry, exhibiting reasonable agreement (r = 0.62, slope = 1.33) with in situ SO2 columns. The mean CMAQ SO2 loading over central and eastern China was 54 kT, approx.30% more than the estimate from OMI SO2 products, 42 kT. These numerical simulations, constrained by observations, indicate that ",50% (35 to 61 %) of the anthropogenic sulfur emissions were transported downwind, and the overall lifetime of tropospheric SO2 was 38+/-7 h