General Attack Research Articles

Cross impact of CO2 phase and impurities on the corrosion behavior for stainless steel and carbon steel in water-containing dense CO2 environments

A series of study was conducted to investigate the corrosion behavior of 2Cr13 stainless steel and X65 carbon steel exposed to water-saturated and water-unsaturated dense CO2 environments with SO2 and O2 impurities in the conditions of 25 °C and 50 °C, 8 MPa. Each test lasted for 48 h. The cross impacts of CO2 phase (liquid phase and supercritical phase), water contents and steel types on the corrosion behavior were elaborately discussed. In water-saturated impure dense CO2 with SO2, SO2/O2 systems, the impacts of single impurity of SO2 and multiple impurities of SO2 and O2 on accelerating general corrosion for both 2Cr13 and X65 steels was much stronger in the supercritical CO2 system than in the liquid CO2 system. At water-unsaturated conditions, 2Cr13 stainless steel exhibited better resistance to the general corrosion attack in liquid and supercritical CO2 with SO2 in comparison with X65 carbon steel, but suffered high risk of localized corrosion in liquid CO2 mixtures. The 2Cr13 and X65 steels could bear higher amounts of water in supercritical CO2 with SO2 systems (∼1300 ppm H2O) than in the liquid CO2 with SO2 systems (<300 ppm H2O).

Coherent attack on oblivious transfer based on single-qubit rotations

Recently a bit-string quantum oblivious transfer (OT) protocol based on single-qubit rotations was proposed (Rodrigues et al 2017 J. Phys. A: Math. Theor. 50 205301) and proven secure against few-qubit measurements. However, it was left as an open question whether the protocol remains secure against general attacks. Here, we close the gap by showing that if the receiver Bob can perform collective measurements on all qubits, then he can learn Alice’s secret message with a probability close to one. Thus the protocol fails to meet the security criterion of OT.

Resilient Consensus with Mobile Detectors Against Malicious Attacks

This paper investigates the problem of resilient consensus under malicious attacks for multiagent systems. Compared with most of existing works, a more general attack model is considered, where malicious agents can neighbor and collude with each other and the number of tolerable attacks is not limited by the network connectivity, which makes the problem more challenging. To solve this problem, we exploit the mobile agents as the detectors, and design the resilient consensus algorithm with mobile detectors (MRCA). MRCA includes basic average iteration process and the detection algorithms of both static and mobile agents. We prove that under MRCA, malicious agents will be detected by mobile agents and isolated by normal agents in finite time in expectation and thus the convergence can be achieved. We also show that MRCA can tolerate neighboring malicious attacks and the number of tolerable attacks is not limited by the network connectivity. Simulations are conducted to demonstrate the effectiveness of MRCA and validate the correctness of the theoretical results.

Corrosion behavior of a 3 % Cr tubing steel in a CO2 saturated high-salinity brine

Abstract Corrosion behavior of 3 wt.-% Chromium (3Cr) tubing steel in CO2 saturated high-salinity brine was investigated by using an autoclave in the laboratory. The partial pressure of CO2 and the Cl− concentration were fixed at 0.2 MPa and 139552 mg × l−1, respectively. The water cut was varied from 20 to 100 vol.-%, and the temperature was varied from 50 to 110 °C. For comparison, the corrosion behaviors of N80 carbon steel and 13 wt.-% Cr (13Cr) martensitic stainless steel were tested in the same conditions. The surface morphologies and chemical composition of corrosion product layers were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDS) technologies. The results show that the 3Cr steel's corrosion rate increased as water cut increased, especially when the water cut exceeded 70 vol.-%. Serious general corrosion and local attack occurred on the 3Cr samples in a 0.2 MPa CO2 and 139552 mg × l−1 Cl− corrosion environment. The product layer structure of 3Cr steel in high-salinity brine is demonstrated. When the chloride ion concentration is high enough, the Cr-enriched layer no longer provides sufficient protection against the chloride ion penetration and pitting attacks may occur.

Knowledge-Concealing Evidencing of Knowledge About a Quantum State.

Bob has a black box that emits a single pure state qudit which is, from his perspective, uniformly distributed. Alice wishes to give Bob evidence that she has knowledge about the emitted state while giving him little or no information about it. We show that zero-knowledge evidencing of such knowledge is impossible in quantum relativistic protocols, extending a previous result of Horodecki, Horodecki, and Horodecki. We also show that no such protocol can be both sound and complete. We present a new quantum relativistic protocol which we conjecture to be close to optimal in security against Alice and which reveals little knowledge to Bob, for large dimension d. We analyze its security against general attacks by Bob and restricted attacks by Alice.

Entanglement generation secure against general attacks

We present a security proof for establishing private entanglement by means of recurrence-type entanglement distillation protocols over noisy quantum channels. We consider protocols where the local devices are imperfect, and show that nonetheless a confidential quantum channel can be established, and used to e.g. perform distributed quantum computation in a secure manner. While our results are not fully device independent (which we argue to be unachievable in settings with quantum outputs), our proof holds for arbitrary channel noise and noisy local operations, and even in the case where the eavesdropper learns the noise. Our approach relies on non-trivial properties of distillation protocols which are used in conjunction with de-Finetti and post-selection-type techniques to reduce a general quantum attack in a non-asymptotic scenario to an i.i.d. setting. As a side result, we also provide entanglement distillation protocols for non-i.i.d. input states.

Analysis and Improvement of Large Payload Bidirectional Quantum Secure Direct Communication Without Information Leakage

As we know, the information leakage problem should be avoided in a secure quantum communication protocol. Unfortunately, it is found that this problem does exist in the large payload bidirectional quantum secure direct communication (BQSDC) protocol (Ye Int. J. Quantum. Inf. 11(5), 1350051 2013) which is based on entanglement swapping between any two Greenberger-Horne-Zeilinger (GHZ) states. To be specific, one half of the information interchanged in this protocol is leaked out unconsciously without any active attack from an eavesdropper. Afterward, this BQSDC protocol is revised to the one without information leakage. It is shown that the improved BQSDC protocol is secure against the general individual attack and has some obvious features compared with the original one.

A Study of General Attacks on Elliptic Curve Discrete Logarithm Problem over Prime Field and Binary Field

This paper begins by describing basic properties of finite field and elliptic curve cryptography over prime field and binary field. Then we discuss the discrete logarithm problem for elliptic curves and its properties. We study the general common attacks on elliptic curve discrete logarithm problem such as the Baby Step, Giant Step method, Pollard’s rho method and Pohlig-Hellman method, and describe in detail experiments of these attacks over prime field and binary field. The paper finishes by describing expected running time of the attacks and suggesting strong elliptic curves that are not susceptible to these attacks.

A Study of General Attacks on Elliptic Curve Discrete Logarithm Problem over Prime Field and Binary Field

A Study of General Attacks on Elliptic Curve Discrete Logarithm Problem over Prime Field and Binary Field

Security Issues in Ultralightweight RFID Authentication Protocols

Ultralightweight RFID authentication protocols have attracted much attention from both fields of science and industry in recent years due to their high efficiencies and extensive applicability. However, many studies have shown that the published ultralightweight protocols are vulnerable to various kinds of malicious attacks, which generally are empirical analysis based and protocol dependent. A general and comprehensive study of these security issues is still absent. To supplement theory study in this area, this paper propose general attack models of three most serious attacks: de-synchronization attack, replay attack and full disclosure attack, for ultralightweight RFID protocols. To formalize the de-synchronization attack, we define an artificial function named FindIndex to analyze the ability of an ultralightweight RFID protocol to keep its data integrity. The proposed de-synchronization attack can break synchronization between RFID tag and database of most ultralightweight protocols with considerable success rates. Our replay attack demonstrates the uselessness of all existing redundancy mechanisms used to solve problems caused by losing final messages. That means all the protocols adopting redundancy mechanisms that store old secrets in one side or both sides cannot resist the proposed replay attack. Furthermore, we develop full-disclosure attacks for T-function based and rotation based RFID protocols, respectively. The described full-disclosure attacks are quite effective and can reveal some or all secrets in RFID tags. Our study shows the most common design flaws in those RFID protocols so that researchers are still faced with challenges to develop a secure ultralightweight RFID protocol.

Cryptanalysis of A New Method of Cryptography using Laplace Transform Hyperbolic Functions

Although Laplace Transform is a good application field in the design of cryptosystems, many encryption algorithm proposals become unsatisfactory for secure communication since cryptanalysis studies are not sufficient. One of the important factors resulting in poor proposals is the fact that security analysis of the proposed encryption algorithms is performed with only statistical tests and experimental results. In this study, a general attack scenario was given in order to conduct security analyses of Laplace Transform based cryptosystems. The application of proposed general attack scenario was shown on recently proposed Laplace Transform based encryption scheme.

Effects of curative and preventive chemical cleaning processes on fouled steam generator tubes in nuclear power plants

Magnetite (Fe3O4) deposits in the secondary circuit of nuclear pressurized water reactors (PWRs), lead to the fouling of the steam generators (SG) which decreases their thermal performances and increases the risk of corrosion of the SG tubes. As a counteraction, preventive and curative chemical cleanings (CCC) are industrially implemented to remove oxides sludges and deposits in SGs. The use of chelating agents in chemical cleaning processes could affect the passive layer of SG tubes, and modify their surface reactivity. In order to better understand these phenomena, two experimental loops have been designed and operated: the FORTRAND loop to perform and investigate SG tube oxidation, fouling and refouling and the ECCLIPS loop used to investigate the effects of the chemical cleanings.A three steps strategy has been implemented as follows: (i) reproducing magnetite deposits on oxidized SG tubes, (ii) applying three different industrial chemical cleaning procedures (a curative and two preventive ones) and (iii) studying the redeposition (refouling) of magnetite. The fluid physico-chemical conditions upon these steps have been thoroughly followed and controlled.Magnetite deposits formed on the SG tubes upon the first fouling have been characterized by scanning and transmission electron microscopies (SEM and TEM) and X-ray diffraction (XRD). They are shown to be composed of a dense layer of small magnetite crystals. Secondly, three different SG industrial cleaning processes were reproduced. Their timing and thermo-chemical conditions were strictly respected and they were found to dissolve most of the fouling deposit. Disperse magnetite crystallites were present on the tube surface. Moreover, TEM cross-section images showed that no general attack of the tube passive layer occurred.Finally, the cleaned tubes were fouled again in the FORTRAND loop using the same experimental conditions as for the first fouling step. It could be concluded that chemical cleanings have no effect on the fouling kinetics of the SG tubes for a short one month period and that the amount of deposit formed before and after the cleanings was identical. The small crystallite dense layer observed before cleaning was not present on refouled tubes and the size of the crystallites was bigger after the cleanings. For a short time period, this morphology could result in the formation of a fouling deposit with more porosity. As the increase of deposit porosity can impact the thermal transfer at the SG tube surface, morphological changes, hardly predictable, could be important for the SG thermal performance after chemical cleaning. For a longer period, frequent SG cleaning applications should prevent the densification of the deposit and thus delay performance loss over time. To the best of our knowledge, this experimental program is the first study of chemical cleaning impacts on SG tubes reactivity.

Quantum identity authentication with single photon

Quantum identity authentication with single photons is proposed in the paper. It can verify a user's identity without exposing to an authentication key information. The protocol guarantees high efficiency in that it can verify two bits of authentication information using just a single photon. The security of our authentication scheme is analyzed and confirmed in the case of a general attack. Moreover, the proposed protocol is practicable with current technology. Our quantum identity authentication protocol does not require quantum memory registration and any entangled photon sources.

Online template attacks

Template attacks are a special kind of side-channel attacks that work in two stages. In a first stage, the attacker builds up a database of template traces collected from a device which is identical to the attacked device, but under the attacker’s control. In the second stage, traces from the target device are compared to the template traces to recover the secret key. In the context of attacking elliptic curve scalar multiplication with template attacks, one can interleave template generation and template matching and reduce the amount of template traces. This paper enhances the power of this technique by defining and applying the concept of online template attacks, a general attack technique with minimal assumptions for an attacker, who has very very limited control over the template device. We show that online template attacks need only one power consumption trace of a scalar multiplication on the target device; they are thus suitable not only against ECDSA and static elliptic curve Diffie–Hellman (ECDH), but also against elliptic curve scalar multiplication in ephemeral ECDH. In addition, online template attacks need only one template trace per scalar bit and they can be applied to a broad variety of scalar multiplication algorithms. To demonstrate the power of online template attacks, we recover scalar bits of a scalar multiplication using the double-and-add-always algorithm on a twisted Edwards curve running on a smartcard with an ATmega163 CPU.

Monitoring of continuous-variable quantum key distribution system in real environment.

How to guarantee the practical security of continuous-variable quantum key distribution (CVQKD) system has been an important issue in the quantum cryptography applications. In contrast to the previous practical security strategies, which focus on the intercept-resend attack or the Gaussian attack, we investigate the practical security strategy based on a general attack, i.e., an arbitrated individual attack or collective attack on the system by Eve in this paper. The low bound of intensity disturbance of the local oscillator signal for eavesdropper successfully concealing herself is obtained, considering all noises can be used by Eve in the practical environment. Furthermore, we obtain an optimal monitoring condition for the practical CVQKD system so that legitimate communicators can monitor the general attack in real-time. As examples, practical security of two special systems, i.e., the Gaussian modulated coherent state CVQKD system and the middle-based CVQKD system, are investigated under the intercept-resend attacks.

The Role of Civil Society in the War of Indonesia Independence : A Case Study in the Battle Against the Allied Forces In Sukabumi 1945-1946

The revolution of Sukabumi is closely related to the role of many kyai, ulama and pesantren’s leaders in its process. They had great power to encourage people’s spirit and emotion. This success was gained by using their religious language to communicate. They used the concept of jihad fi sabilillah. The climax of the revolution is the battle against the invader’s alliance along the road of Cigombong– Ciranjang that was followed by a series of battle,such as Bojongkokosan battle,causing the bombing of Cibadak by Alliance air force; Gekbrong battle; and general attack involving army force, ulama, people’s organization and the students of pesantrens.

Sufficiency of quantum non-Gaussianity for discrete-variable quantum key distribution over noisy channels

Quantum key distribution can be enhanced and extended if nonclassical single-photon states of light are used. We study a connection between the security of quantum key distribution and quantum non-Gaussianity of light arriving at the receiver's detection system after the propagation through a noisy quantum channel, being under full control of an eavesdropper performing general collective attacks. We show that while quantum nonclassicality exhibited by the light arriving at the receiver's station is a necessary indication of the security of the discrete-variable protocols, quantum non-Gaussianity can be a sufficient indication of their security. Therefore, checking for non-Gaussianity of this light by performing standard autocorrelation function measurement can be used for prior verification of the usability of prepare-and-measure schemes. It can play similar role to the prior verification of the quantum correlations sufficient to violate Bell inequalities for entanglement-based protocols.

Additive Classical Capacity of Quantum Channels Assisted by Noisy Entanglement.

We give a capacity formula for the classical information transmission over a noisy quantum channel, with separable encoding by the sender and limited resources provided by the receiver's preshared ancilla. Instead of a pure state, we consider the signal-ancilla pair in a mixed state, purified by a "witness." Thus, the signal-witness correlation limits the resource available from the signal-ancilla correlation. Our formula characterizes the utility of different forms of resources, including noisy or limited entanglement assistance, for classical communication. With separable encoding, the sender's signals across multiple channel uses are still allowed to be entangled, yet our capacity formula is additive. In particular, for generalized covariant channels, our capacity formula has a simple closed form. Moreover, our additive capacity formula upper bounds the general coherent attack's information gain in various two-way quantum key distribution protocols. For Gaussian protocols, the additivity of the formula indicates that the collective Gaussian attack is the most powerful.

Security of Continuous-Variable Quantum Key Distribution via a Gaussian de Finetti Reduction.

Establishing the security of continuous-variable quantum key distribution against general attacks in a realistic finite-size regime is an outstanding open problem in the field of theoretical quantum cryptography if we restrict our attention to protocols that rely on the exchange of coherent states. Indeed, techniques based on the uncertainty principle are not known to work for such protocols, and the usual tools based on de Finetti reductions only provide security for unrealistically large block lengths. We address this problem here by considering a new type of Gaussian de Finetti reduction, that exploits the invariance of some continuous-variable protocols under the action of the unitary group U(n) (instead of the symmetric group S_{n} as in usual de Finetti theorems), and by introducing generalized SU(2,2) coherent states. Crucially, combined with an energy test, this allows us to truncate the Hilbert space globally instead as at the single-mode level as in previous approaches that failed to provide security in realistic conditions. Our reduction shows that it is sufficient to prove the security of these protocols against Gaussian collective attacks in order to obtain security against general attacks, thereby confirming rigorously the widely held belief that Gaussian attacks are indeed optimal against such protocols.

Attack Detection in Sensor Network Target Localization Systems With Quantized Data

We consider a sensor network focused on target localization, where sensors measure the signal strength emitted from the target. Each measurement is quantized to one bit and sent to the fusion center. A general attack is considered at some sensors that attempts to cause the fusion center to produce an inaccurate estimation of the target location with a large mean-square-error. The attack is a combination of man-in-the-middle, hacking, and spoofing attacks that can effectively change both signals going into and coming out of the sensor nodes in a realistic manner. We show that the essential effect of attacks is to alter the estimated distance between the target and each attacked sensor to a different extent, giving rise to a geometric inconsistency among the attacked and unattacked sensors. Hence, with the help of two secure sensors, a class of detectors are proposed to detect the attacked sensors by scrutinizing the existence of the geometric inconsistency. We show that the false alarm and miss probabilities of the proposed detectors decrease exponentially as the number of measurement samples increases, which implies that for sufficiently large number of samples, the proposed detectors can identify the attacked and unattacked sensors with any required accuracy.