The increasing demand in 5G wireless systems has brought significant improvement in transmission speed with lower latency, especially in ultra-dense networks. The demand of privacy and security are becoming more critical in such large scale wireless networks. Different from traditional encryption methods, in this paper, we discussed the physical layer security features in large scale social networks. The opportunities in large scale social networks are summarized in physical, link and upper layer using the cross layer optimization, traditional physical layer security will meet new problems pending to be tackled. Also, we summarized the challenges due to some ideal considerations: the detection of wire-tap users, the utilization of high dynamic range and the information exchanging in cross layer design.

Physical Layer Security in 5G Based Large Scale Social Networks: Opportunities and Challenges

Application of Internet of Things (IoT) in health, defense, banking, and other confidential information transfer urges the need for secure IoT. As most of the IoT devices are resource-limited (antennas, bandwidth, energy), securing the information transfer has always been a challenge. Looking at a solution for enhancing the security of single antenna, single carrier, energy efficient devices, we propose a novel scheme, channel-based mapping diversity. This scheme uses the inherent randomness of the wireless channel and multiple mappings available for an ${M}$ -ary phase shift keying constellation in confusing an eavesdropper. When the legitimate and the eavesdropper channels are independent of each other, it is shown that a symbol error rate (SER) of $\frac {(M-1)}{M}$ is induced at the eavesdropper. Whereas, when the channels are correlated, optimal and suboptimal strategies at source and eavesdropper are derived for their respective optimal performances. Further, a closed-form expression for a lower-bound on the SER at the eavesdropper is derived. Simulation results show that for the correlated case, as SNR at the eavesdropper increases, SER initially decreases, later saturates to a relatively high SER, hence making the job of the eavesdropper difficult in getting the legitimate data. Furthermore, the effect of the correlation is more pronounced on SER at higher levels of correlation. This indicates that for practical correlation scenarios, SER is high enough to confuse the eavesdropper.

Exploiting Mapping Diversity for Enhancing Security at Physical Layer in the Internet of Things

A survey on security issues of 5G NR: Perspective of artificial dust and artificial rain

With the surge of ubiquitous demand for high-complexity and quality mobile Internet-of-things (IoT) services, new cooperative relaying paradigms have emerged. Motivated by the long and unpredictable end-to-end communication in relay-aided IoT networks, there is a need to introduce novel modulation schemes for very low bit error rate (BER) communications. In this paper, a practical modulation mapping scheme has been proposed to reduce decoding errors. Specifically, a hybrid automatic repeat request (HARQ) system has been used with an intermediate relay to transfer a message from a source to a destination. The design of modulation mapping has been optimized by first formulating the objective as the quadratic assignment problem. Later, the solution to the mapping problem is provided using an iterative search method. To validate the proposed solution, extensive simulations have been performed in MATLAB. The results show that the proposed solution outperforms the conventional relay retransmission and the heuristic design approaches.

https://www.mdpi.com/2076-3417/10/6/2126/pdf

Efficient Modulation Scheme for Intermediate Relay-Aided IoT Networks

With the emergence of new digital trends like Internet of Things (IoT), more industry actors and technical committees pursue research in utilising such technologies as they promise a better and optimised management, improved energy efficiency and a better quality living through a wide array of value-added services. However, as sensing, actuation, communication and control become increasingly more sophisticated, such promising data-driven systems generate, process, and exchange larger amounts of security-critical and privacy-sensitive data, which makes them attractive targets of attacks. In turn this affirms the importance of trustworthiness in IoT and emphasises the need of a solid technical and regulatory foundation. The goal of this paper is to first introduce the concept of trustworthiness in IoT, its main pillars namely, security, privacy and data protection, and then analyse the state-of-the-art in research and standardisation for each of these subareas. Throughout the paper, we develop and refer to Unmanned Aerial Vehicles (UAVs) as a promising value-added service example of mobile IoT devices. The paper then presents a thorough gap analysis and concludes with recommendations for future work.

Trustworthiness in IoT – A Standards Gap Analysis on Security, Data Protection and Privacy

Demand of minimal hardware requirement and low energy consumption for internet of things (IoT) has gained the importance of techniques enhancing the physical layer security Looking at this, we propose a channel-based mapping diversity (CBMD) scheme for a source (S), destination (D) pair to increase the average bit error rate (ABER) at an eavesdropper (E) CBMD leads to an ABER of 05 at E when the channels between S — D and S — E are independent In the case where S — D and S — E are correlated (due to the proximity of E at D), we derive an optimal strategy at E which leads to the best performance at E We also derive an optimal strategy at S, assuming E uses its optimal strategy, thereby, considering the worst case scenario A sub-optimal strategy is also proposed at S which does not require any statistical information about the link S — E and hence, has low implementation complexity We analyze the variation of ABER at E with the signal to noise ratio (SNR) and the channel correlation coefficient Our simulation results demonstrate that CBMD indeed leads to significant performance degradation at E even at moderate channel correlation for a properly chosen strategy

Channel-based mapping diversity for enhancing the physical layer security in the Internet of Things

In this letter, we propose a novel scheme for enhancing the security of the information transfer between resource-limited devices. We select a pulse from a set of $T$ -orthogonal pulses for shaping the data at source ( $S$ ) based on legitimate channel state information (CSI). A destination ( $D$ ) having the CSI, properly samples the output of the matched filter. An eavesdropper ( $E$ ) having no knowledge of the legitimate CSI, may or may not sample correctly, thereby, inducing artificial intersymbol interference (ISI) at the $E$ . We also consider a case where the $S-E$ link is correlated with the $S-D$ link (when $E$ and $D$ are closely located). We derive optimal thresholds at $E$ , $S$ for switching the selection of a pulse in maximizing and minimizing the achievable rate at $E$ , respectively. We derive closed-form expressions for upper bound and lower bound on the secrecy outage probability (SOP) for the independent case. Simulation results show that unlike at $D$ , the symbol error rate (SER) at $E$ saturates at a high SER due to the induced ISI.

Channel-Aware Artificial Intersymbol Interference for Enhancing Physical Layer Security

In this paper, we consider a two-tier downlink scenario, where femtocell users are interested in receiving both macrocell and femtocell information simultaneously at a single frequency (joint two-tier downlink reception). Unlike in conventional handsets, which use orthogonal schemes for accommodating two-tier downlink reception, we propose two non-orthogonal schemes based on precoding-aided spatial modulation (PSM) for handling cross-tier downlink interference. In both the proposed schemes, the femtocell information is conveyed as an active antenna index at the user (spatial symbol), while the macrocell information is conveyed as a phase shift keyed (PSK) symbol on the activated antenna. Appropriate precoders are designed at femtocell base station (FBS) and macrocell base station (MBS) to manage the cross-tier interference. We derive average transmit powers at the MBS and all FBSs for both the schemes. We also optimize the transmit powers of both the schemes at a given target signal-to-noise ratio (SNR). Further, we exploit the existing cross-tier interference as a source of artificial interference for enhancing the physical layer security of femtocell users. We derive secrecy rates of the proposed schemes, and corroborate the analytical expressions derived throughout the paper with simulation results.

Precoding-Aided Spatial Modulation Assisted Joint Two-Tier Downlink Reception

In this letter, we propose a generalized precoding-aided secure time-domain index modulation (PSTD-IM) scheme for enhancing the rate and secrecy of the system. Unlike in the conventional time-domain index modulation (TD-IM), where a single (or a set of) Nyquist pulse is activated over multiple symbol periods at the transmitter, in this letter, the pulse (or the set of pulses) is activated at the legitimate receiver, thereby securing the information transfer. In addition, we project artificial noise (AN) onto the null space of the legitimate user and degrade the signal-to-noise-ratio (SNR) at the eavesdropper. In fact, we propose the above-discussed generalized PSTD-IM for a multi-user downlink scenario, where each user is expected to receive an independent TD-IM symbol. We analyze the secrecy rate and derive a closed-form expression for an upper bound on the average bit error rate (ABER) of the proposed scheme. Further, we show that the proposed scheme achieves transmit diversity as opposed to the existing spatial modulation schemes.

Sasi Vinay Pechetti

Papers

Exploiting Mapping Diversity for Enhancing Security at Physical Layer in the Internet of Things

Channel-based mapping diversity for enhancing the physical layer security in the Internet of Things

Channel-Aware Artificial Intersymbol Interference for Enhancing Physical Layer Security

Precoding-Aided Spatial Modulation Assisted Joint Two-Tier Downlink Reception

Precoding-Aided Secure Time-Domain Index Modulation