The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Boris Kopf - One of the best experts on this subject based on the ideXlab platform.
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formally bounding the Side Channel leakage in unknown message attacks
European Symposium on Research in Computer Security, 2008Co-Authors: Michael Backes, Boris KopfAbstract:We propose a novel approach for quantifying a system's resistance to unknown-message Side-Channel attacks. The approach is based on a measure of the secret information that an attacker can extract from a system from a given number of Side-Channel measurements. We provide an algorithm to compute this measure, and we use it to analyze the resistance of hardware implementations of cryptographic algorithms with respect to timing attacks. In particular, we show that message-blinding --- the common countermeasure against timing attacks --- reduces the rate at which information about the secret is leaked, but that the complete information is still eventually revealed. Finally, we compare information measures corresponding to unknown-message, known-message, and chosen-message attackers and show that they form a strict hierarchy.
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formally bounding the Side Channel leakage in unknown message attacks
IACR Cryptology ePrint Archive, 2008Co-Authors: Michael Backes, Boris KopfAbstract:We propose a novel approach for quantifying a system’s resistance to unknown-message Side-Channel attacks. The approach is based on a measure of the secret information that an attacker can extract from a system from a given number of Side-Channel measurements. We provide an algorithm to compute this measure, and we use it to analyze the resistance of hardware implementations of cryptographic algorithms with respect to power and timing attacks. In particular, we show that messageblinding – the common countermeasure against timing attacks – reduces the rate at which information about the secret is leaked, but that the complete information is still eventually revealed. Finally, we compare information measures corresponding to unknown-message, known-message, and chosen-message attackers and show that they form a strict hierarchy.
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an information theoretic model for adaptive Side Channel attacks
Computer and Communications Security, 2007Co-Authors: Boris Kopf, David BasinAbstract:We present a model of adaptive Side-Channel attacks which we combine with information-theoretic metrics to quantify the information revealed to an attacker. This allows us to express an attacker's remaining uncertainty about a secret as a function of the number of Side-Channel measurements made. We present algorithms and approximation techniques for computing this measure. We also give examples of how they can be used to analyze the resistance of hardware implementations of cryptographic functions to both timing and power attacks.
Stefano Pirandola - One of the best experts on this subject based on the ideXlab platform.
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Side Channel free quantum key distribution
Physical Review Letters, 2012Co-Authors: Samuel L Braunstein, Stefano PirandolaAbstract:Quantum key distribution (QKD) offers the promise of absolutely secure communications. However, proofs of absolute security often assume perfect implementation from theory to experiment. Thus, existing systems may be prone to insidious Side-Channel attacks that rely on flaws in experimental implementation. Here we replace all real Channels with virtual Channels in a QKD protocol, making the relevant detectors and settings inSide private spaces inaccessible while simultaneously acting as a Hilbert space filter to eliminate Side-Channel attacks. By using a quantum memory we find that we are able to bound the secret-key rate below by the entanglement-distillation rate computed over the distributed states.
Fan Zhang - One of the best experts on this subject based on the ideXlab platform.
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energy loss evaluation in a Side Channel pump under different wrapping angles using entropy production method
International Communications in Heat and Mass Transfer, 2020Co-Authors: Fan Zhang, Desmond Appiah, Jinfeng Zhang, Shouqi Yuan, Feng Hong, Kofi Asamoah Adupoku, Xueyuan WeiAbstract:Abstract Flow losses in common vanned pumps such as centrifugal pumps have been widely studied, while less research attention has been paid to Side Channel pumps that are commonly used in the food processing and petrochemical industries. Therefore, this study reveals the exact regions of high hydraulic losses for Side Channel pump models using the entropy loss production method. Numerical calculations based on unsteady Reynolds-averaged Navier–Stokes (RANS) equations coupled with the shear stress transport (SST) k-ω turbulence model were used to acquire the entropy dissipative components of the flow. The accuracy of the numerical method was validated by comparing the experimental measurements of pump case 2 with a wrapping angle of 30°. The results showed that the impeller domain produced higher losses compared to the Side Channel. The impeller generally recorded the highest loss coefficient of ζD' at 144 whiles the Side Channel recorded the lowest at ζD' 0.2) compared to the outer radius and decreased gently with increasing flows. Notwithstanding, the high losses produced in all pump cases, case 1 produced the highest energy losses compared with the other pump cases even though it had the best hydraulic performance. Thus, this study contributes to the fundamental knowledge of Side Channel pumps by providing the regions of high-energy losses for further optimization of the main geometrical parts especially the impeller. This will subsequently help improve the performance and operational reliability of Side Channel pumps and enhance its applications.
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transient flow characterization in energy conversion of a Side Channel pump under different blade suction angles
Energy, 2018Co-Authors: Fan Zhang, Desmond Appiah, Jinfeng Zhang, Shouqi Yuan, Majeed Koranteng Osman, Ke ChenAbstract:The flow in a Side Channel pump exhibits complex, three-dimensional and unsteady features. The present study investigates the transient flow interaction between the moving impeller region and the static Side Channel in a Side Channel pump which consists of 24 blades and a circular Side Channel. In this study, the transient flow features under different blade suction angle profiles have been investigated. The transient pressure distribution, velocity field, streamline plots, and mass flow exchange between the impeller and Side Channel are analyzed. Comparison shows that the Side Channel pump's flow mechanism is influenced by irregular flow characteristics and a number of vortex impulses at certain positions. Thus, zones of large vortices that cause low pump efficiency are demonstrated. The pressure fluctuation in the Side Channel pump is greatly influenced by the flow exchange between the impeller region and the Side Channel, and the pressure fluctuation frequency is related to the flow exchange frequency. This work helps understand the transient flow characteristics and serves as a guide for conducting further research in high-efficiency Side Channel pumps.
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effects of the geometrical conditions on the performance of a Side Channel pump a review
International Journal of Energy Research, 2018Co-Authors: Desmond Appiah, Fan Zhang, Shouqi Yuan, Majeed Koranteng OsmanAbstract:Summary The Side Channel pump, which is a common energy conversion equipment, has undergone high developmental trends and has become very popular in recent times because of its wide applications in many fields. The Side Channel pump is a type of regenerative pump that plays a role in between the centrifugal pump and the positive displacement pump. This kind of pump delivers a high head at relatively small flows compared with other axial and centrifugal pumps even though it requires a low specific speed. Depending on the number of impellers used, the Side Channel pump can be single-stage or multistage. This paper first focuses on the physical principle behind the internal flow characteristics illustrating the complex flow and the energy from the blade to the fluid and the Side Channel inSide the pump. Further discussions disclosed that the hydraulic performance of the pump greatly depends on the variations of the geometrical parameters. This review draws conclusion that enhancement of the computational modeling techniques will improve the efficiency of this pump, thereby broadening its applications.
Desmond Appiah - One of the best experts on this subject based on the ideXlab platform.
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energy loss evaluation in a Side Channel pump under different wrapping angles using entropy production method
International Communications in Heat and Mass Transfer, 2020Co-Authors: Fan Zhang, Desmond Appiah, Jinfeng Zhang, Shouqi Yuan, Feng Hong, Kofi Asamoah Adupoku, Xueyuan WeiAbstract:Abstract Flow losses in common vanned pumps such as centrifugal pumps have been widely studied, while less research attention has been paid to Side Channel pumps that are commonly used in the food processing and petrochemical industries. Therefore, this study reveals the exact regions of high hydraulic losses for Side Channel pump models using the entropy loss production method. Numerical calculations based on unsteady Reynolds-averaged Navier–Stokes (RANS) equations coupled with the shear stress transport (SST) k-ω turbulence model were used to acquire the entropy dissipative components of the flow. The accuracy of the numerical method was validated by comparing the experimental measurements of pump case 2 with a wrapping angle of 30°. The results showed that the impeller domain produced higher losses compared to the Side Channel. The impeller generally recorded the highest loss coefficient of ζD' at 144 whiles the Side Channel recorded the lowest at ζD' 0.2) compared to the outer radius and decreased gently with increasing flows. Notwithstanding, the high losses produced in all pump cases, case 1 produced the highest energy losses compared with the other pump cases even though it had the best hydraulic performance. Thus, this study contributes to the fundamental knowledge of Side Channel pumps by providing the regions of high-energy losses for further optimization of the main geometrical parts especially the impeller. This will subsequently help improve the performance and operational reliability of Side Channel pumps and enhance its applications.
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transient flow characterization in energy conversion of a Side Channel pump under different blade suction angles
Energy, 2018Co-Authors: Fan Zhang, Desmond Appiah, Jinfeng Zhang, Shouqi Yuan, Majeed Koranteng Osman, Ke ChenAbstract:The flow in a Side Channel pump exhibits complex, three-dimensional and unsteady features. The present study investigates the transient flow interaction between the moving impeller region and the static Side Channel in a Side Channel pump which consists of 24 blades and a circular Side Channel. In this study, the transient flow features under different blade suction angle profiles have been investigated. The transient pressure distribution, velocity field, streamline plots, and mass flow exchange between the impeller and Side Channel are analyzed. Comparison shows that the Side Channel pump's flow mechanism is influenced by irregular flow characteristics and a number of vortex impulses at certain positions. Thus, zones of large vortices that cause low pump efficiency are demonstrated. The pressure fluctuation in the Side Channel pump is greatly influenced by the flow exchange between the impeller region and the Side Channel, and the pressure fluctuation frequency is related to the flow exchange frequency. This work helps understand the transient flow characteristics and serves as a guide for conducting further research in high-efficiency Side Channel pumps.
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effects of the geometrical conditions on the performance of a Side Channel pump a review
International Journal of Energy Research, 2018Co-Authors: Desmond Appiah, Fan Zhang, Shouqi Yuan, Majeed Koranteng OsmanAbstract:Summary The Side Channel pump, which is a common energy conversion equipment, has undergone high developmental trends and has become very popular in recent times because of its wide applications in many fields. The Side Channel pump is a type of regenerative pump that plays a role in between the centrifugal pump and the positive displacement pump. This kind of pump delivers a high head at relatively small flows compared with other axial and centrifugal pumps even though it requires a low specific speed. Depending on the number of impellers used, the Side Channel pump can be single-stage or multistage. This paper first focuses on the physical principle behind the internal flow characteristics illustrating the complex flow and the energy from the blade to the fluid and the Side Channel inSide the pump. Further discussions disclosed that the hydraulic performance of the pump greatly depends on the variations of the geometrical parameters. This review draws conclusion that enhancement of the computational modeling techniques will improve the efficiency of this pump, thereby broadening its applications.
Prabhat Mishra - One of the best experts on this subject based on the ideXlab platform.
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scalable test generation for trojan detection using Side Channel analysis
IEEE Transactions on Information Forensics and Security, 2018Co-Authors: Yuanwen Huang, Swarup Bhunia, Prabhat MishraAbstract:Hardware Trojan detection has emerged as a critical challenge to ensure security and trustworthiness of integrated circuits. A vast majority of research efforts in this area has utilized Side-Channel analysis for Trojan detection. Functional test generation for logic testing is a promising alternative but it may not be helpful if a Trojan cannot be fully activated or the Trojan effect cannot be propagated to the observable outputs. Side-Channel analysis, on the other hand, can achieve significantly higher detection coverage for Trojans of all types/sizes, since it does not require activation/propagation of an unknown Trojan. However, they have often limited effectiveness due to poor detection sensitivity under large process variations and small Trojan footprint in Side-Channel signature. In this paper, we address this critical problem through a novel Side-Channel-aware test generation approach, based on a concept of multiple excitation of rare switching (MERS), that can significantly increase Trojan detection sensitivity. This paper makes several important contributions: 1) it presents in detail a scalable statistical test generation method, which can generate high-quality test set for creating high relative activity in arbitrary Trojan instances; 2) it analyzes the effectiveness of generated test set in terms of Trojan coverage; and 3) it describes two judicious reordering methods that can further tune the test set and greatly improve the Side Channel sensitivity. Simulation results demonstrate that the tests generated by MERS can significantly increase the Trojans sensitivity, thereby making Trojan detection effective using Side-Channel analysis.
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mers statistical test generation for Side Channel analysis based trojan detection
Computer and Communications Security, 2016Co-Authors: Yuanwen Huang, Swarup Bhunia, Prabhat MishraAbstract:Hardware Trojan detection has emerged as a critical challenge to ensure security and trustworthiness of integrated circuits. A vast majority of research efforts in this area has utilized Side-Channel analysis for Trojan detection. Functional test generation for logic testing is a promising alternative but it may not be helpful if a Trojan cannot be fully activated or the Trojan effect cannot be propagated to the observable outputs. Side-Channel analysis, on the other hand, can achieve significantly higher detection coverage for Trojans of all types/sizes, since it does not require activation/propagation of an unknown Trojan. However, they have often limited effectiveness due to poor detection sensitivity under large process variations and small Trojan footprint in Side-Channel signature. In this paper, we address this critical problem through a novel Side-Channel-aware test generation approach, based on a concept of Multiple Excitation of Rare Switching (MERS), that can significantly increase Trojan detection sensitivity. The paper makes several important contributions: i) it presents in detail the statistical test generation method, which can generate high-quality testset for creating high relative activity in arbitrary Trojan instances; ii) it analyzes the effectiveness of generated testset in terms of Trojan coverage; and iii) it describes two judicious reordering methods can further tune the testset and greatly improve the Side Channel sensitivity. Simulation results demonstrate that the tests generated by MERS can significantly increase the Trojans sensitivity, thereby making Trojan detection effective using Side-Channel analysis.
