Biblio

Physical Layer Security (PLS) is used to accomplish perfect secure communication between intended network nodes, while the eavesdropper gets zero information. In this paper, a smart antenna technology i.e., Massive multiple-input-multiple-output (mMIMO) and Non-Orthogonal Multiple Access (NOMA) technology is being used to enhance the secrecy performance of a 5G communication network. Small scale Rayleigh fading channels, as well as large scale pathway loss, have to be taken into consideration. An eavesdropper with multiple antennas, an amplify-and-forward (AF) relay with multi antenna has been proposed. Spider Monkey Algorithm (SMO) is used in adding Artificial Noise (AN) for refining secrecy rate. The findings revealed that the suggested technique improves the security and the quality of Wireless communication.

Deep learning (DL) is becoming popular as a new tool for many applications in wireless communication systems. However, for many classification tasks (e.g., modulation classification) it has been shown that DL-based wireless systems are susceptible to adversarial examples; adversarial examples are well-crafted malicious inputs to the neural network (NN) with the objective to cause erroneous outputs. In this paper, we extend this to regression problems and show that adversarial attacks can break DL-based power allocation in the downlink of a massive multiple-input-multiple-output (maMIMO) network. Specifically, we extend the fast gradient sign method (FGSM), momentum iterative FGSM, and projected gradient descent adversarial attacks in the context of power allocation in a maMIMO system. We benchmark the performance of these attacks and show that with a small perturbation in the input of the NN, the white-box attacks can result in infeasible solutions up to 86%. Furthermore, we investigate the performance of black-box attacks. All the evaluations conducted in this work are based on an open dataset and NN models, which are publicly available.

This work studies an energy-efficient jamming scheme for enhancing physical layer security in visible light communication (VLC). We consider a VLC system where multiple LED luminaries are deployed together with a legitimate user (i.e., Bob) and passive eavesdroppers (i.e., Eves). In such a scenario, the closest LED luminary to Bob serves as the transmitter while the rest of the luminaries act as jammers transmitting artificial noise (AN) to possibly degrade the quality of Eves' channels. A joint design of precoder and AN is then investigated to maximize the energy efficiency (EE) of the communication channel to Bob while ensuring a certain amount of AN power to confuse Eves. To solve the design problem, we make use of a combination of the Dinkelbach and convex-concave procedure (CCCP), which guarantees to converge to a local optimum.

We consider the physical layer security (PLS) of non-orthogonal multiple access (NOMA) enabled multiple-input multiple-output (MIMO) visible light communication systems in the presence of a passive eavesdropper (Eve). In order to disrupt the decoding process at Eve, we propose a novel precoding scheme reinforced with random constellation coding. Multiple legitimate users (Bobs) will be served simultaneously using NOMA. For the proposed precoder design, we exploit the slow-fading characteristics of the visible light channel so that the transmitted symbols are successfully decoded at Bob, while Eve suffers from very high bit error ratios (BERs) due to precoding-induced jamming. Via computer simulations, we show that Bob can successfully decode their own information in various user configurations and receiver diversities. It is also shown that the BER at Eve's side is increased to the 0.5-level for similar and the asymmetrical positioning of Bob with respect to the transmitter, thus PLS is ensured by the proposed preceding technique.

This work studies the optimization of spectrum pooling for the downlink of a multi-tenant Cloud Radio Access Network (C-RAN) system in the presence of inter-tenant privacy constraints. The spectrum available for downlink transmission is partitioned into private and shared subbands, and the participating operators cooperate to serve the user equipments (UEs) on the shared subband. The network of each operator consists of a cloud processor (CP) that is connected to proprietary radio units (RUs) by means of finite-capacity fronthaul links. In order to enable inter-operator cooperation, the CPs of the participating operators are also connected by finite-capacity backhaul links. Inter-operator cooperation may hence result in loss of privacy. The problem of optimizing the bandwidth allocation, precoding, and fronthaul/backhaul compression strategies is tackled under constraints on backhaul and fronthaul capacity, as well as on per-RU transmit power and inter-onerator privacy.

Edge caching has received much attention as a promising technique to overcome the stringent latency and data hungry challenges in the future generation wireless networks. Meanwhile, full-duplex (FD) transmission can potentially double the spectral efficiency by allowing a node to receive and transmit simultaneously. In this paper, we study a cache-aided FD system via delivery time analysis and optimization. In the considered system, an edge node (EN) operates in FD mode and serves users via wireless channels. Two optimization problems are formulated to minimize the largest delivery time based on the two popular linear beamforming zero-forcing and minimum mean square error designs. Since the formulated problems are non-convex due to the self-interference at the EN, we propose two iterative optimization algorithms based on the inner approximation method. The convergence of the proposed iterative algorithms is analytically guaranteed. Finally, the impacts of caching and the advantages of the FD system over the half-duplex (HD) counterpart are demonstrated via numerical results.

We consider the problem of designing repair efficient distributed storage systems, which are information-theoretically secure against a passive eavesdropper that can gain access to a limited number of storage nodes. We present a framework that enables design of a broad range of secure storage codes through a joint construction of inner and outer codes. As case studies, we focus on two specific families of storage codes: (i) minimum storage regenerating (MSR) codes, and (ii) maximally recoverable (MR) codes, which are a class of locally repairable codes (LRCs). The main idea of this framework is to utilize the existing constructions of storage codes to jointly design an outer coset code and inner storage code. Finally, we present a construction of an outer coset code over small field size to secure locally repairable codes presented by Tamo and Barg for the special case of an eavesdropper that can observe any subset of nodes of maximum possible size.

Secret key establishment is considered to be one of the main challenging issues in cryptography. Many security algorithms are implemented in practice using complicated mathematical methods to exchange secret keys, but those methods are not desirable in power limited terminals such as cellular and sensor networks. In this paper, we propose a physical layer method for exchanging secret key bits in precoding based multi-input multi-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems. The proposed method uniquely relates the key bits to the indices of the precoding matrix used for MIMO channel precoding. The basic idea of the technique is to utilize a MIMO-OFDM precoding codebook. Comparative analysis with respect to the average number of mismatch bits, named key error rate (KER), shows an interesting lead for the new method relative to existing work. In addition, it will be shown that the proposed technique requires lower computation per byte per secret key.

This paper proposed a MIMO cross-layer precoding secure communications via pattern controlled by higher layer cryptography. By contrast to physical layer security system, the proposed scheme could enhance the security in adverse situations where the physical layer security hardly to be deal with. Two One typical situation is considered. One is that the attackers have the ideal CSI and another is eavesdropper's channel are highly correlated to legitimate channel. Our scheme integrates the upper layer with physical layer secure together to gaurantee the security in real communication system. Extensive theoretical analysis and simulations are conducted to demonstrate its effectiveness. The proposed method is feasible to spread in many other communicate scenarios.