• Journal of Positioning, Navigation, and Timing
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• 제10권3호
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• pp.169-177
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• 2021

In this paper, we propose a novel global navigation satellite system (GNSS) spoofing detection technique through an array antenna-based direction of arrival (DoA) estimation of satellite and spoofer. Specifically, we consider a sophisticated GNSS spoofing attack scenario where the spoofer can accurately mimic the multiple pseudo-random number (PRN) signals since the spoofer has its own GNSS receiver and knows the location of the target receiver in advance. The target GNSS receiver precisely estimates the DoA of all PRN signals using compressed sensing-based orthogonal matching pursuit (OMP) even with a small number of samples, and it performs spoofing detection from the DoA estimation results of all PRN signals. In addition, considering the initial situation of a sophisticated spoofing attack scenario, we designed the algorithm to have high spoofing detection performance regardless of the relative spoofing signal power. Therefore, we do not consider the assumption in which the power of the spoofing signal is about 3 dB greater than that of the authentic signal. Then, we introduce design parameters to get high true detection probability and low false alarm probability in tandem by considering the condition for the presence of signal sources and the proximity of the DoA between authentic signals. Through computer simulations, we compare the DoA estimation performance between the conventional signal direction estimation method and the OMP algorithm in few samples. Finally, we show in the sophisticated spoofing attack scenario that the proposed spoofing detection technique using OMP-based estimated DoA of all PRN signals outperforms the conventional spoofing detection scheme in terms of true detection and false alarm probability.

• International Journal of Internet, Broadcasting and Communication
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• 제15권3호
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• pp.149-159
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• 2023

Web application security education that can provide practical experience is needed to reduce damage caused by the recent increase in web application vulnerabilities and to strengthen security. In this paper, we proposed a scenario-based web application education method, applied the proposed method to classes, and analyzed the results. In order to increase the effectiveness of scenario-based education, a real-life practice environment to perform scenarios and instructions to be performed by learners are needed. As an example of the proposed method, instructions to be performed by learners from the viewpoint of the attacker and the victim were shown in a practice environment to teach XSS and SQL injection vulnerabilities. After applying the proposed method to the class for students majoring in cyber security, when the lecture evaluation results were analyzed, it was shown that the learner's interest, understanding, and major ability all improved.

• 인터넷정보학회논문지
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• 제24권6호
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• pp.107-117
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• 2023

사이버 공간에서 이루어지는 전투 행위가 군의 주요 임무체계 및 무기체계에 어떠한 영향을 미치는지를 평가할 수 있어야 한다. 사이버공격에 의한 임무영향을 사이버 M&S로 분석하기 위해서는 대상이 되는 임무체계와 사이버전 요소를 모델로 구축하고, 시뮬레이션을 위한 시나리오를 저작하여야 한다. 사이버전에 의한 임무영향 분석 관련 연구는 미국을 중심으로 많은 연구가 수행되었으며, 기존의 연구에서는 물리전장과 사이버전장에 대해 별개로 시나리오를 저작하였다. 임무영향 분석의 정확도를 높이기 위해서는 물리전장 모델과 사이버전장 모델을 결합한 시뮬레이션 환경을 구축하고, 임무 시나리오와 사이버공격/방어 시나리오를 통합해서 저작할 수 있어야 한다. 또한 물리전장과 사이버전장은 업무영역이 상이함을 고려하여 시나리오를 효율적으로 저작할 수 있는 방법이 필요하다. 본 논문에서는 임무체계 정보를 이용하여 시나리오 저작에 필요한 자료를 사전에 작성하고, 선작업된 자료를 이용하여 통합시나리오를 저작하는 방법을 제안한다. 제안한 방법은 시나리오 저작도구의 설계에 반영하여 개발하고 있으며, 제안 방법을 입증하기 위해 대화력전 분야의 통합시나리오 저작을 수행하였다. 향후, 제안한 방법을 반영한 시나리오 저작도구를 활용하면 임무영향 분석을 위한 통합시나리오를 짧은 시간에 쉽게 저작할 수 있게 될 것이다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권9호
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• pp.3858-3869
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• 2020

In this paper, we propose a hash-chain based friendly force identification protocol for personal combatants equipped with a personal combat system in a tactical wireless network. It is imperative in military operations to effectively and quickly identify friendly forces. If the identification of friendly forces is not correct, this can cause friendly fire. In current ground operations, the identification of friendly forces by personal combatants is neither secure nor safe. To address this issue, the proposed protocol uses a hash-chain to determine if a detected person is friendly. Only friendly forces with the same materials that are assigned before they deploy can construct an initial hash-chain. Moreover, the hash-chain is changed at specific times. The performance of the proposed protocol is evaluated on the assumption that the secret key is leaked, which is the worst scenario in the security research field. We verify that the proposed protocol is secure for the various attack scenarios, such as message replay attack, fabrication attack, and Denial of Service attack.

• 디지털산업정보학회논문지
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• 제19권3호
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• pp.25-38
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• 2023

Instrumentation and control systems measure and control various variables of nuclear facilities to operate nuclear power plants safely. A diverse protection system, a representative instrumentation and control system, generates a reactor trip and turbine trip signal by high pressure in a pressurizer and containment to satisfy the design requirements 10CFR50.62. Also, it generates an auxiliary feedwater actuation signal by low water levels in steam generators. Cybersecurity has become more critical as digital technology is gradually applied to solve problems such as performance degradation due to aging of analog equipment, increased maintenance costs, and product discontinuation. This paper analyzed possible cybersecurity threat scenarios in the diverse protection system using attack trees. Based on the analyzed cybersecurity threat scenario, we calculated the probability of attack occurrence and confirmed the cybersecurity risk in connection with the asset value.

• 한국멀티미디어학회논문지
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• 제25권2호
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• pp.221-236
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• 2022

BLE protocol prevents MITM attacks with user interaction through some input/output devices such as keyboard or display. Therefore, If it use a device which has no input/output facility, it can be vulnerable to MITM attack. If messages to be sent to a control device is forged by MITM attack, the device can be abnormally operated by malicious attack from attacker. Therefore, we describes a scenario which has the vulnerabilities of the BLE network in this paper and propose countermeasure method against MITM attacks integrity violations. Its mechanism provides data confidentiality and integrity with MD5 and security key distribution of Diffie Helman's method. In order to verify the effectiveness of the countermeasure method proposed in this paper, we have conducted the experiments. ​As experiments, the message was sent 200 times and all of them successfully detected whether there was MITM attack or not. In addition, it took at most about 4.2ms delay time with proposed countermeasure method between devices even attacking was going on. It is expected that more secure data transmission can be achieved between IoT devices on a BLE network through the method proposed.

• 한국군사과학기술학회지
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• 제26권2호
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• pp.197-204
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• 2023

The importance of each warfighting function for Army TIGER unit attack drones is measured using the AHP technique. As a result, the importance of attack drones is high in the order of maneuver, firepower, intelligence, command/control, protection, and operation sustainment, but the importance of maneuver, firepower, and intelligence are almost similar. In addition, it is analyzed that attack drones capable of carrying out day and night missions by being equipped with an EO/IR sensor and being commanded/controlled in conjunction with the C4I system to eliminate threats with small bombs or aircraft collisions is needed. Finally, based on the results of this study, a virtual battle scenario for attack drones is proposed.

• 인터넷정보학회논문지
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• 제25권2호
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• pp.1-9
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• 2024

연합학습은 보안 및 프라이버시 측면에서 중앙 집중식 방법보다 안전하도록 설계되었음에도 불구하고 여전히 많은 취약점을 내재한다. 적대적 공격(adversarial attack)을 수행하는 공격자는 신중하게 제작된 입력 데이터, 즉 적대적 예제(adversarial examples)를 클라이언트의 학습 데이터에 주입하여 딥러닝 모델을 의도적으로 조작하여 오분류를 유도한다. 이에 대한 보편적인 방어 전략은 이른바 적대적 학습(adversarial training)으로 적대적 예제들의 특성을 선제적으로 모델에 학습시키는 것이다. 기존의 연구에서는 모든 클라이언트가 적대적 공격 하에 있는 상황을 가정하는데 연합학습의 클라이언트 수가 매우 많음을 고려하면 실제와는 거리가 있다. 본 논문에서는 클라이언트의 일부가 공격 하에 있는 시나리오에서 적대적 학습의 양상을 실험적으로 살핀다. 우리는 실험을 통해 적대적 예제에 대한 분류 정확도가 증가하면 정상 샘플에 대한 분류 정확도의 감소하는 트레이드오프 관계를 가짐을 밝혔다. 이러한 트레이드오프 관계를 효과적으로 활용하기 위해 클라이언트가 자신이 공격받는지 여부에 따라 손실함수를 적응적으로 선택하여 적대적 학습을 수행하는 방법을 제시한다.

• 한국군사과학기술학회지
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• 제20권2호
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• pp.279-288
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• 2017

The Material Transportation Capability Analysis Method in North Korea includes adversary's activities such as destruction of bridge which is one kind of choke points in the road network and surprise attack against resupply march unit. Also, the amount of damage on choke points in the road network and repair time depending on repair unit commitment must be reflected. In this study, a scenario encompassing plausible resupply transportation circumstances while counterattacking into NK will be established. Then, based on such scenario, a simulation model will be established and the result of simulation will be compared to the results of numeric example which has been used in the ROK Army. We demonstrate, through a certain Corps operation area, that the Scenario-based Simulation Model results predict the performance of resupply operation very well. Therefore, it makes sustainment planners and commanders do activities which is suitable for battlefield and should be used in the real situation. It is also a stochastic model.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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• pp.291-294
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• 2000

This paper describes on the threats in the MPLS Network. Also we discuss on attack scenario that are Unauthenticated Access, Data disclosure and Data modification. Finally we discuss and suggest the best various Security of solutions in MPLS network