2012 International Conference on Computing, Networking and Communications (ICNC)

Achievable secrecy rates in physical layer secure systems with a helping interferer

Arsenia Chorti, H. Vincent Poor

Published Jan 1, 2012• 23 citations

Abstract

Various physical-layer techniques have so far been proposed to achieve perfect secrecy in wireless communication systems. In this framework, an approach is investigated to enhance secrecy using a helping interferer transmitted by a friendly node in the network, aiming at confusing a passive eavesdropper. Commonly, such physical layer security approaches rely on the injection of a noise-like signal to intentionally degrade the eavesdropper capacity. Instead, the use of a jamming signal with the same probability mass function as that of the actual data is proposed here. The gains of this approach are investigated via extensive symbol error rate measurements and evaluations of the achievable secrecy rates.

DOI: 10.1109/iccnc.2012.6167408

Related papers

Helping interferer physical layer security strategies for M-QAM and M-PSK systems

Arsenia Chorti

Physical layer security encompasses information theoretic approaches that could guarantee perfect secrecy in wireless communication systems. In this framework, helping interferer strategies rely on intentionally creating confusion at a potential eavesdropper by injecting a jamming signal. In cases where the information signal has a Gaussian probability density function (pdf) it has been demonstrated that the optimal jamming signal, under an overall power constraint, should also be Gaussian. However, in practical communication systems where data symbols are typically drawn from discrete uniform probability mass functions (pmf), commonly M-ary Quadrature Amplitude and M-ary Phase Shift Keying modulation schemes, the structure of the optimal jamming signal is still an open question. In the present work we aim at shedding light into this question. Our approach is based on formulating a secrecy capacity maximization problem by expressing the optimal arbitrary helping interferer pdf as a mixture of unknown Gaussians. The proposed approximation is well-suited for jamming signals of practical interest, i.e. Gaussian or M-QAM interferers and reveals that in certain scenarios it is advantageous to use jamming signals whose statistical structure resembles the data rather than the noise.

Conference on Information Sciences and SystemsMar 1, 201214 citations

Jamming Power Estimation Technique Under Wireless Physical Layer Security in Presence of an Eavesdropper

Mohammed Ahmed Salem, Azlan Bin Abd.Aziz, Mohamad Yusoff Alias +1 more

In this paper, we study the secrecy performance of a communication scenario between a transmitter and a receiver nodes in the presence of a passive eavesdropper node. In order to degrade the eavesdropper capacity, a friendly jammer node is employed to generate jamming signal. The jamming signal interferes and confuses the eavesdropper node. This paper proposes a jamming power estimation technique to achieve secrecy performance requirements. In this paper, we utilize the relation between the jamming power and the probability of secrecy outage to derive a closed form expression of the jamming power estimation technique. Based on the results, the proposed estimation technique meets the secrecy performance requirements.

International Conference on Smart Computing and Communications (ICSCC)Jun 1, 20193 citations

Improving security for future wireless networks through friendly jamming

Mark Adams

As the number of connected devices and the importance of mobile communications continue to increase, a greater emphasis must be placed on security. Due to the broadcast nature of wireless communications, wireless networks are very exposed to eavesdropping. While this can be addressed above the physical layers using encryption, this still allows the attacker to receive the message and future work may allow decryption. Physical layer security is an approach to security which exploits the wireless channel to prevent the attacker from decoding the message. This thesis examines the use of friendly jamming, in which some nodes in a network broadcast white noise in order to degrade the channel between the legitimate transmitter and the eavesdropper. We address two problems related to the use of friendly jamming to improve physical layer security. The first problem is routing a signal through a network while using the remaining nodes as jammers to secure the signal. This is solved as two convex problems of allocating power to the jammers and routing the signal using those jammers to secure the transmission. This is shown to be a feasible method to increase security in a network. The second problem is estimating the self-interference channel (SIC) without using a calibration period for full-duplex jamming receivers. As the transmitter cannot transmit while the receiver estimates its SIC using a half duplex pilot signal, eliminating the calibration period can represent a significant capacity gain. Estimating the channel while receiving the desired signal causes it to act as an additional noise source, but this is shown to be overcome through the use of long estimation times. Our proposed scheme is able to increase the secrecy capacity of the system over that of calibration based estimation.

Jan 1, 20172 citations

An approach for secure wireless communication using friendly noise

Parag Aggarwal, Aditya Trivedi

As the need of highly secure data transmission in wireless communication has increased rapidly, physical layer security gains a lots of attention recently. The transmission of confidential data between two legitimate users in the existence of the passive eavesdropper with quasi-static Rayleigh channel is considered. A new technique is proposed in which a friendly noise is incorporated with confidential data bearing signal such that it preserves the integrity of the signal and does not degrade the legitimate link. This friendly noise acts as jamming signal for eavesdropper. The analytical expression for secrecy outage probability of the proposed technique for both single and multiple antennas eavesdropper is derived. The secrecy performance of proposed technique is compared with the traditional direct transmission and the cooperative jamming schemes. The asymptotic nature of the outage probability is also studied for the different parameters. Numerical results are also presented to verify the analytical expressions of proposed model, which show that the proposed technique is better than the traditional direct transmission and the cooperative jamming schemes.

International Conference on Advances in Computing, Communications and Informatics (ICACCI)Sep 1, 20144 citations

Physical Layer Security Jamming: Theoretical Limits and Practical Designs in Wireless Networks

Kanapathippillai Cumanan, Hong Xing, Peng Xu +5 more

Physical layer security has been recently recognized as a promising new design paradigm to provide security in wireless networks. In addition to the existing conventional cryptographic methods, physical layer security exploits the dynamics of fading channels to enhance secured wireless links. In this approach, jamming plays a key role by generating noise signals to confuse the potential eavesdroppers, and significantly improves quality and reliability of secure communications between legitimate terminals. This article presents theoretical limits and practical designs of jamming approaches for physical layer security. In particular, the theoretical limits explore the achievable secrecy rates of user cooperation-based jamming whilst the centralized and game theoretic-based precoding techniques are reviewed for practical implementations. In addition, the emerging wireless energy harvesting techniques are exploited to harvest the required energy to transmit jamming signals. Future directions of these approaches and the associated research challenges are also briefly outlined.

arXiv:1701.05764IEEE AccessDec 17, 201691 citations

Enhancing physical layer security in wireless networks with cooperative approaches

Weigang Liu

Motivated by recent developments in wireless communication, this thesis aims to characterize the secrecy performance in several types of typical wireless networks. Advanced techniques are designed and evaluated to enhance physical layer security in these networks with realistic assumptions, such as signal propagation loss, random node distribution and non-instantaneous channel state information (CSI). The first part of the thesis investigates secret communication through relay-assisted cognitive interference channel. The primary and secondary base stations (PBS and SBS) communicate with the primary and secondary receivers (PR and SR) respectively in the presence of multiple eavesdroppers. The SBS is allowed to transmit simultaneously with the PBS over the same spectrum instead of waiting for an idle channel. To improve security, cognitive relays transmit cooperative jamming (CJ) signals to create additional interferences in the direction of the eavesdroppers. Two CJ schemes are proposed to improve the secrecy rate of cognitive interference channels depending on the structure of cooperative relays. In the scheme where the multiple-antenna relay transmits weighted jamming signals, the combined approach of CJ and beamforming is investigated. In the scheme with multiple relays transmitting weighted jamming signals, the combined approach of CJ and relay selection is analyzed. Numerical results show that both these two schemes are effective in improving physical layer security of cognitive interference channel. In the second part, the focus is shifted to physical layer security in a random wireless network where both legitimate and eavesdropping nodes are randomly distributed. Three scenarios are analyzed to investigate the impact of various factors on security. In scenario one, the basic scheme is studied without a protected zone and interference. The probability distribution function (PDF) of channel gain with both fading and path loss has been derived and further applied to derive secrecy connectivity and ergodic secrecy capacity. In the second scenario, we studied using a protected zone surrounding the source node to enhance security where interference is absent. Both the cases that eavesdroppers are aware and unaware of the protected zone boundary are investigated. Based on the above scenarios, further deployment of the protected zones at legitimate receivers is designed to convert detrimental interference into a beneficial factor. Numerical results are investigated to check the reliability of the PDF for reciprocal of channel gain and to analyze the impact of protected zones on secrecy performance. In the third part, physical layer security in the downlink transmission of cellular network is studied. To model the repulsive property of the cellular network planning, we assume that the base stations (BSs) follow the Mat´ern hard-core point process (HCPP), while the eavesdroppers are deployed as an independent Poisson point process (PPP). The distribution function of the distances from a typical point to the nodes of the HCPP is derived. The noise-limited and interference-limited cellular networks are investigated by applying the fractional frequency reuse (FFR) in the system. For the noise-limited network, we derive the secrecy outage probability with two different strategies, i.e. the best BS serve and the nearest BS serve, by analyzing the statistics of channel gains. For the interference-limited network with the nearest BS serve, two transmission schemes are analyzed, i.e., transmission with and without the FFR. Numerical results reveal that both the schemes of transmitting with the best BS and the application of the FFR are beneficial for physical layer security in the downlink cellular networks, while the improvement due

Nov 29, 20160 citations