Passive Eavesdropping Attacks Research Articles

UAV Trajectory and Multi-User Beamforming Optimization for Clustered Users Against Passive Eavesdropping Attacks With Unknown CSI

This paper tackles the fundamental passive eavesdropping problem in modern wireless communications in which the location and the channel state information (CSI) of the attackers are unknown. In this regard, we propose deploying an unmanned aerial vehicle (UAV) that serves as a mobile aerial relay (AR) to help ground base station (GBS) support a subset of vulnerable users. More precisely, our solution (1) clusters the single-antenna users in two groups to be either served by the GBS directly or via the AR, (2) employs optimal multi-user beamforming to the directly served users, and (3) optimizes the AR's 3D position, its multi-user beamforming matrix and transmit powers by combining closed-form solutions with machine learning techniques. Specifically, we design a plain beamforming and power optimization combined with a deep reinforcement learning (DRL) algorithm for an AR to optimize its trajectory for the security maximization of the served users. Numerical results show that the multi-user multiple input, single output (MU-MISO) system split between a GBS and an AR with optimized transmission parameters without knowledge of the eavesdropping channels achieves high secrecy capacities that scale well with increasing the number of users.

QoS-aware secure transmission design for VLC with semi-grant-free NOMA scheme.

This work aims to enhance the physical layer security (PLS) of non-orthogonal multiple access (NOMA) aided indoor visible light communication (VLC) system with semi-grant-free (SGF) transmission scheme, in which a grant-free (GF) user shares the same resource block with a grant-based (GB) user whose quality of service (QoS) must be strictly guaranteed. Besides, the GF user is also provided with an acceptable QoS experience, which is closely aligned with the practical application. Both active and passive eavesdropping attacks are discussed in this work, where users' random distributions are taken into account. Specifically, to maximize the secrecy rate of the GB user in the presence of an active eavesdropper, the optimal power allocation policy is obtained in exact closed-form and the user fairness is then assessed by Jain's fairness index. Moreover, the secrecy outage performance of the GB user is analyzed in the presence of the passive eavesdropping attack. Both exact and asymptotic theoretical expressions for the secrecy outage probability (SOP) of the GB user are derived, respectively. Furthermore, the effective secrecy throughput (EST) is investigated on the basis of the derived SOP expression. Through simulations, it is found that the PLS of this VLC system can be significantly improved by the proposed optimal power allocation scheme. The radius of the protected zone, the outage target rate for the GF user, and the secrecy target rate for the GB user would have pronounced impacts on the PLS and user fairness performance of this SGF-NOMA assisted indoor VLC system. The maximum EST will increase with the increasing transmit power and it is hardly influenced by the target rate for the GF user. This work will benefit the design of indoor VLC system.

Physical-layer encryption and authentication scheme based on SKGD and 4D hyper-chaos.

In this paper, a scheme to realize encryption and digital identity authentication at the same time is proposed for enhancing the physical-layer security of point-to-point optical links (PPOL). Exploiting identity code encrypted by the key as authentication information effectively resists passive eavesdropping attacks in fingerprint authentication. The proposed scheme theoretically realizes secure key generation and distribution (SKGD) by phase noise estimation of the optical channel and the generation of identity codes with good randomness and unpredictability by the four-dimensional (4D) hyper-chaotic system. The local laser, erbium doped fiber amplifier (EDFA), and public channel provide the entropy source of uniqueness and randomness to extract symmetric key sequences for legitimate partners. The simulation conducted in a quadrature phase shift keying (QPSK) PPOL system over 100km standard single mode fiber verify successfully that 0.95Gbit/s error-free SKGD. The unpredictability and high sensitivity to the initial value and control parameters of the 4D hyper-chaotic system provide a huge space of ~10125 for identity codes, which is sufficient to resist exhaustive attack. With the proposed scheme, the security level of key and identity can be increased markedly.

Blockchain-Based Data Acquisition with Privacy Protection in UAV Cluster Network

The unmanned aerial vehicle (UAV) self-organizing network is composed of multiple UAVs with autonomous capabilities according to a certain structure and scale, which can quickly and accurately complete complex tasks such as path planning, situational awareness, and information transmission. Due to the openness of the network, the UAV cluster is more vulnerable to passive eavesdropping, active interference, and other attacks, which makes the system face serious security threats. This paper proposes a Blockchain-Based Data Acquisition (BDA) scheme with privacy protection to address the data privacy and identity authentication problems in the UAV-assisted data acquisition scenario. Each UAV cluster has an aggregate unmanned aerial vehicle (AGV) that can batch-verify the acquisition reports within its administrative domain. After successful verification, AGV adds its signcrypted ciphertext to the aggregation and uploads it to the blockchain for storage. There are two chains in the blockchain that store the public key information of registered entities and the aggregated reports, respectively. The security analysis shows that the BDA construction can protect the privacy and authenticity of acquisition data, and effectively resist a malicious key generation center and the public-key substitution attack. It also provides unforgeability to acquisition reports under the Elliptic Curve Discrete Logarithm Problem (ECDLP) assumption. The performance analysis demonstrates that compared with other schemes, the proposed BDA construction has lower computational complexity and is more suitable for the UAV cluster network with limited computing power and storage capacity.

Detection and defense of active attacks for generating secret key from wireless channels in static environment

In quasi-static or static environments, generating secret key from wireless channels is bad randomness and vulnerable to active attacks. To improve randomness of the generated secret key, singular value decomposition (SVD) techniques are used to construct equivalent wireless channels in multiple-input multiple-output (MIMO) systems. SVD techniques and private pilot are used to detect active attacks by authenticating sender based on wireless channels. To defend passive eavesdropping and active attacks, the concept of one time pad is used to encrypt wireless channels with private pilot. The proposed SKG scheme based on private pilot and SVD techniques can not only detect whether SKG suffers active attacks, but also defend man-in-the-middle attack, impersonation attack, signal injection attack, passive eavesdropping. What is more, the SKG scheme can obtain higher SKG rate and randomness than the approach via random beam-forming. Theoretical analysis and simulation results prove the above results again.

Leakage Rate Analysis for Artificial Noise Assisted Massive MIMO With Non-Coherent Passive Eavesdropper in Block-Fading

Massive MIMO is one of the salient techniques for achieving high spectral efficiency in next generation wireless networks. Recently, a combined strategy of the massive MIMO and the artificial noise (AN), namely, {\it AN assisted massive MIMO (ANAM)} has recently been actively investigated for security enhancement. However, most of previous studies on the ANAM have been built upon the full channel state information (CSI) assumption at the eavesdropper (ED), which may be too pessimistic to provide meaningful information on the security since the channel uncertainty of the ED may degrade its decoding ability. In this paper, we provide more sophisticated investigation on the performance of the ANAM system assuming that the CSI of the ED channels are unknown to both the BS and the ED or partially known to the ED. We measure the secrecy in terms of both the leakage rate to the ED and the secrecy rate to the legitimate users, and characterize their upper and lower bounds in the high SNR regime as a function of the number of ED antennas, the number of data and AN signal dimensions, and coherence time. Finally, from numerical results, we demonstrate the accuracy of our analysis and highlight the security potential of the ANAM system against the passive eavesdropping attack.

Secrecy Rate Analysis of UAV-Enabled mmWave Networks Using Matérn Hardcore Point Processes

Communications aided by low-altitude unmanned aerial vehicles (UAVs) have emerged as an effective solution to provide large coverage and dynamic capacity for both military and civilian applications, especially in unexpected scenarios. However, because of their broad coverage, UAV communications are prone to passive eavesdropping attacks. This paper analyzes the secrecy performance of UAVs networks at the millimeter wave band and takes into account unique features of air-to-ground channels and practical constraints of UAV deployment. To be specific, it explores the 3-D antenna gain in the air-to-ground links and uses the Matern hardcore point process to guarantee the safety distance between the randomly deployed UAV base stations. In addition, we propose the transmit jamming strategy to improve the secrecy performance in which part of UAVs send jamming signals to confound the eavesdroppers. Simulation results verify our analysis and demonstrate the impact of different system parameters on the achievable secrecy rate. It is also revealed that optimizing the density of jamming UAVs will significantly improve security of UAV-enabled networks.

Game theoretic approach of eavesdropping attack in millimeter-wave-based WPANs with directional antennas

In this paper, we propose a game theoretic framework to analyze a passive eavesdropping attack in millimeter-wave-based wireless personal area networks. As the interaction between defenders and attackers in network security issues can be considered as a game, devices can be considered as players. Usually a player has insufficient information of other players such as strategies and payoffs especially in static situation. We assume that each player selects its strategy based on its belief about the information on opponents and the belief is known as a prior probability. The Bayesian game model is a relevant framework for this situation. It is assumed that each device is equipped with a directional antenna and knows the channel state. In the analysis, the exposure region (ER) that is determined by the antennas directions of players is considered and the ratio of ER for the total area of a network is calculated by using the probability density function of distance between players. The optimal strategies of two players, a transmitter and an eavesdropper, are derived in terms of Bayesian Nash equilibriums and payoffs for the players are computed for pure and mixed strategies in static situation. The analysis shows how the effects of using a directional antenna and the prior probability of transmitters belief are involved in the Nash equilibriums. Numerical results show the equilibriums and two players payoffs. Those values depend on several parameters such as beamwidth and prior probability of belief as well as its opponents strategies. It also shows the effect of directional antennas in the eavesdropping attack; the use of directional antenna seems to increase the transmitters payoff, while it seems to decrease the eavesdroppers payoff. The obtained results will provide the criteria for selecting appropriate strategy to transmitters when an eavesdropper exists in the network.

Security threats and protection procedures for optical networks

This study addresses the issues of optical network survivability to attacks in the optical physical layer. The authors comprehensively review and discuss the vulnerability of optical networks towards various types of security threats that could appear in the network optical layer: passive eavesdropping attacks and active optical attacks like in-band jamming, out-of-band crosstalk attacks, amplifier attacks and physical infrastructure attacks. They describe and discuss several protection procedures and monitoring techniques to improve network attack survivability. Numerical simulation performances of some attacks and protection schemes are also provided.

A Secure Privacy-Preserving Data Aggregation Scheme Based on Bilinear ElGamal Cryptosystem for Remote Health Monitoring Systems

Due to advancements in the development of wireless medical sensing devices and wireless communication technologies, the wireless body area network (WBAN) has become an eminent part of e-healthcare systems. WBAN uses medical sensors to continuously monitor and collect the physiological parameters of a patient’s health and send them to a remote medical server through a portable digital assistance (PDA)/mobile. Due to limitations in communication, such as power, storage, and the computational capabilities of sensors, data aggregation techniques are used to reduce the communication overhead in real-time data transmission in WBAN. However, since the WBAN transmits sensitive health data, data security and data privacy are a major concern. In this paper, we propose a secure privacy-preserving data aggregation (SPPDA) scheme based on bilinear pairing for remote health monitoring systems to improve data aggregation efficiency and data privacy. Our proposed SPPDA scheme utilizes the homomorphic property of the bilinear ElGamal cryptosystem to perform privacy-preserving secure computation and combines it with the aggregate signature scheme, enabling data authenticity/integrity in the WBAN. The proposed SPPDA scheme is proved to be semantically secure under the decisional bilinear Diffie–Hellman assumption. Security analysis demonstrates that our proposed scheme preserves data confidentiality, data authenticity, and data privacy; it also resists passive eavesdropping and replay attacks. A performance evaluation based on simulation results and a comparison of computational cost with related schemes show that data aggregation and batch verification at the PDA significantly reduce communication and transmission overhead and support efficient computation at the remote server.

MIO: Enhancing Wireless Communications Security Through Physical Layer Multiple Inter-Symbol Obfuscation

Communications security is a critical and increasingly challenging issue in wireless networks. A well-known approach for achieving information-theoretic secrecy relies on deploying artificial noises to blind the intruders’ interception in the physical layer. However, this approach requires a static channel condition for the transmitter and receiver to generate and offset the controllable artificial noise, which can hardly be implemented in real wireless environments. In this paper, we explore the feasibility of symbol obfuscation to defend against the passive eavesdropping attack and fake packet injection attack during the wireless communications. We propose a multiple inter-symbol obfuscation (MIO) scheme, which utilizes a set of artificial noisy symbols (symbols key) to obfuscate the original data symbols in the physical layer. MIO can effectively enhance the wireless communications security. On the one hand, an eavesdropper, without knowing the artificial noisy symbols, cannot correctly decrypt the obfuscated symbols from the eavesdropped packets. On the other hand, a legitimate receiver can easily check the integrity of the symbols key and then reject the fake packets from the received packets. The security analysis reveals that, without considering the initial key, the MIO scheme can achieve information-theoretic secrecy against the passive eavesdropping attack and computational secrecy against the fake packet injection attack. Moreover, we have implemented our approach in a USRP2 testbed and conducted simulations with Simulink tools to validate the effectiveness of MIO in enhancing wireless communications security.

Physical layer security for massive MIMO: An overview on passive eavesdropping and active attacks

This article discusses opportunities and challenges of physical layer security integration in massive multiple-input multiple-output (MaMIMO) systems. Specifically, we first show that MaMIMO itself is robust against passive eavesdropping attacks. We then review a pilot contamination scheme which actively attacks the channel estimation process. This pilot contamination attack is not only dramatically reducing the achievable secrecy capacity but is also difficult to detect. We proceed by reviewing some methods from literature that detect active attacks on MaMIMO. The last part of the paper surveys the open research problems that we believe are the most important to address in the future and give a few promising directions of research to solve them.

Physical Layer Security in Underlay CCRNs with Fixed Transmit Power

In this paper, we investigate physical layer security for multiple decode-and-forward (DF) relaying underlay cognitive radio networks (CRNs) with fixed transmit power at the secondary network against passive eavesdropping attacks. We propose a simple relay selection scheme to improve wireless transmission security based on the instantaneous channel information of all legitimate users and the statistical information about the eavesdropper channels. The closed-form expressions of the probability of non-zero secrecy capacity and the secrecy outage probability (SOP) are derived over independent and non-identically distributed Rayleigh fading environments. Furthermore, we conduct the asymptotic analysis to evaluate the secrecy diversity order performance and prove that full diversity is achieved by using the proposed relay selection. Finally, numerical results are presented to verify the theoretical analysis and depict that primary interference constrain has a significant impact on the secure performance and a proper transmit power for the second transmitters is preferred to be energy-efficient and improve the secure performance.

Efficient techniques of key management and quantum cryptography in RFID networks

An efficient way of handling security keys using quantum cryptography QC for increasing security in radio frequency identification RFID networks is being investigated by network security industries. To establish secure RFID network, communication between any two nodes that hold RFID tags and/or readers merged with existing networks should be protected. In order to maximize the data security and secure transmission around RFID network, theoretical model of the quantum key management KM system based on RFID is introduced as a proposed research. This model not only manages the secure keys but also it defends passive eavesdropping attacks and other potential attacks. Novelties in this research are security keys of which QC is being utilized in RFID network with continuous key updates. To establish future security around RFID networks, efficient KM protocol and QC, which deal with quantum mathematical procedures and quantum physics, should be analyzed without affecting the legacy. Computational complexities in KM are increasing with the large key sizes, which are manageable through QC. To maximize the security and minimize the complexity in KM, QC with Grover's algorithm is introduced as a method in RFID network environments. So, we have proved that a number of operations with key sizes obtained in KM are reduced. In this proposal, QC will help to reduce the complexity of algorithms used in KM protocols and maximize the security. Copyright © 2014 John Wiley & Sons, Ltd.

Experimental passive eavesdropping of Digital Enhanced Cordless Telecommunication voice communications through low‐cost software‐defined radios

AbstractThe flexibility of software‐defined radio (SDR) technology has been proposed to support various applications from the dynamic usage of the radio frequency spectrum to the implementation of radio access technologies in the commercial and military domain. A new generation of low‐cost SDR devices has emerged in the last few years, opening new possibilities to implement inexpensive security attacks against radio protocols and systems. Digital Enhanced Cordless Telecommunication (DECT) is a European Telecommunications Standards Institute standard for short‐range cordless communications with a worldwide installed base. In this paper, we survey the state of art for the application of low‐cost SDRs to the security domain, and we describe a complete implementation of a passive eavesdropping attack against DECT digital voice communication, where the DECT communication is not encrypted. The framework, which implements the attack, has been deployed on two different types of low‐cost SDR platforms to show the flexibility and extendibility of the implementation. The performance of the framework has been evaluated on the basis of different parameters and different approaches, and the experimental results are presented in the paper. The framework has demonstrated its effectiveness to implement an eavesdropping attack against DECT even at great distances with low‐cost equipment.Copyright © 2014 John Wiley & Sons, Ltd.

Chaotic Data Encryption for Long-Distance Monitoring of Nuclear Reactors

A secure long-distance monitoring scheme is proposed for nuclear engineering applications using chaos synchronization and nonlinear observers for online transmittal of operational data, distance monitoring, fault detection, and other related processes. The proposed system consists of three components: (a) chaotic transmitter to encrypt and send signals coming from a message originating system, (b) chaotic receiver to decrypt information signals, and (c) reconstruction of the message originating system using the decrypted signals. The Lorenz chaotic system whose parameters are defined as nonlinear functions of the state variables to improve the security level of the chaos-based communication is considered as the chaotic encrypter. In the receiver section, a nonlinear observer is used to provide synchronization and to decrypt the message signal. A similar nonlinear observer is employed to reconstruct the message originating system state variables from the recovered message signal. Numerical results and case studies against certain passive eavesdropping attacks are provided to demonstrate the resilience of the proposed method. A reduced-order boiling water reactor model is used as the message originating system in the illustrations.

The Subset Keys and Identity Tickets (SKIT) Key Distribution Scheme

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Probabilistic key predistribution schemes (P-KPSs) which place modest demands on hardware are good candidates for securing interactions between resource limited computers. Collusion susceptible P-KPSs are trade-offs between security and complexity. Some facets of complexity include computation, bandwidth, and storage overhead. Metrics for security include resistance to passive eavesdropping attacks, and active message injection attacks. The contributions of this paper are three-fold: 1) a novel P-KPS, the subset keys and identity tickets (SKIT) scheme; 2) a generic KPS model to facilitate comparison of various facets of the complexity of key predistribution schemes; and 3) a new security model to describe the resistance of P-KPSs to active message-injection attacks. The two models are used to show <emphasis emphasistype="boldital">why</emphasis> SKIT has many compelling advantages over existing P-KPSs in the literature. In particular, while placing lower demands on computation, bandwidth and storage overhead, SKIT realizes substantial improvements in resistance to passive and active attacks. </para>

스마트카드와 지문을 이용한 강화된 ID기반의 인증 기법

최근에 KIM03[9]은 지문과 스마트카드를 이용한 ID기반의 인증 기법을 제안하였다. 하지만 Scott[10]은 KIM03의 인증 기법이 소극적 공격(Passive attack)에 취약함을 보였다. 본 논문에서는 KIM03의 인증 기법에 존재하는 문제점을 해결할 수 있는 강화된 ID기반의 인증 기법을 제안한다. 특히, 본 논문에서 제안한 기법은 기존의 ID 기반의 암호화 시스템이 공유하는 문제점인 ID 복구문제(Repairability)를 해결한다. 본 논문에서 제안한 ID 기반의 인증 프로토콜은 ID기반의 암호화 시스템의 장점을 유지하면서 이 방식의 문제점들을 효율적으로 해결한다. Recently, Kim et al. proposed ID-based authentication schemes using smartcards and fingerprints. However, Scott showed that they were vulnerable to the passive eavesdropping attack. Thereby, this paper proposes an enhanced ID-based authentication scheme to solve the problems in Kin et al. scheme. Especially, the proposed scheme solves the ID repairability problem commonly shared in the previous ID based Cryptosystems. The proposed ID-based authentication scheme supports the advantages in the previous ID-based authentication scheme and solves the problems in them effectively.