Sharif Digital Repository

Cooperative relaying can be introduced as a promising approach for data communication in the Internet of Things (IoT), where the source and the destination may be placed far away. In this paper, by taking a variety of realistic hardware imperfections (HWIs) and channels estimation errors (CEEs) into account, the secrecy performance of a three-hop cooperative network with a source, a destination and two consecutive amplify-and-forward (AF) relays is investigated. The relays are considered to be untrusted, i.e., while they are mandatory helpers for data transmission, they may overhear the received signals. We adopt the artificial noise injection scheme, to keep the source message secret from... 

In this research paper, the authors present a comprehensive overview of three key elements of Metaverse-as-a-service (MaaS) platforms: privacy and security, edge computing, and blockchain technology. The study begins by examining security concerns for wireless access to the Metaverse. It then delves into privacy and security issues within the Metaverse from data-centric, learning-centric, and human-centric perspectives. The authors propose novel and less-explored methods to aid mobile network operators and Metaverse service providers in creating secure and private MaaS platforms across various layers of the Metaverse, from access to social interactions. The article also explores the... 

In this paper, we propose a light-weight jamming-resistant scheme for the Internet-of-Things (IoT) in 5G networks to ensure high-quality communication in a two-hop cooperative network. In the considered system model, a source communicates with a destination in the presence of an untrusted relay and a powerful multi-Antenna adversary jammer. The untrusted relay is an authorized necessary helper who may wiretap the confidential information. Meanwhile, the jammer is an external attacker who tries to damage both the training and transmission phases. Different from traditional frequency hopping spread spectrum (FHSS) techniques that require a pre-determined pattern between communicating nodes, in... 

The Internet-of-Things (IoT) spans various applications in healthcare filed, from smart wearable or implantable sensors to remote monitoring of elderly, and medical device networking. In this paper, a jamming-resistant scheme for the healthcare IoT is proposed to provide secure and reliable data transmission in a two-hop cooperative network, where a source communicates with a destination in the presence of an untrusted relay and an active adversary. The untrusted relay is an authorized necessary helper who may wiretap the confidential information, e.g., the secret measured data of a patient, while the jammer is an external attacker who tries to interrupt the communication. Different from... 

Unmanned aerial vehicles (UAVs) are developing rapidly owing to flexible deployment and access services as the air base stations. In this paper, by taking the realistic assumption of imperfect channel state information at transmitter (CSIT), we investigate the robust and secure design of downlink UAV network while considering the worst-case outage constraints due to communication link uncertainties. In our proposed heterogeneous network, comprised of both UAV-cells and macro-users, rate splitting technique is deployed by UAV base-station (UAV-BS) to enhance the system performance in terms of security, power saving, and robustness against imperfect CSIT. Through our proposed design, we... 

In this paper, a learning-aided content-based image transmission scheme is proposed, where a multi-antenna source wishes to securely deliver an image to a legitimate destination in the presence of randomly-distributed passive eavesdroppers (Eves). We take into account the fact that not all regions of an image have the same importance from the security perspective. Hence, we employ a hybrid method to realize both the error-free data delivery of public regions—containing less-important pixels; and an artificial noise (AN)-aided transmission scheme for securing the confidential packets. To reinforce system’s security, fountain-based packet delivery is also adopted, where the source node encodes... 

In this paper, a content-aware medical image transmission scheme is investigated over a multiple-input single-output (MISO) channel in wireless healthcare systems. The multi-antenna-aided access point, as a source node, wishes to wirelessly send medical images of a patient to a trusted destination node, while multiple randomly-located totally passive and non-colluding eavesdroppers (Eves) try to wiretap the transmission. Considering the fact that not all regions of an image have the same importancy level from the security view-point, we first segment the image into two parts: the region of interest (RoI), which more likely contains important diagnostic information regarding the medical image... 

In this article, we propose a lightweight security scheme for ensuring both information confidentiality and transmission resiliency in the Internet-of-Things (IoT) communication. A single-Antenna transmitter communicates with a half-duplex single-Antenna receiver in the presence of a sophisticated multiple-Antenna-Aided passive eavesdropper and a multiple-Antenna-Assisted hostile jammer (HJ). A low-complexity artificial noise (AN) injection scheme is proposed for drowning out the eavesdropper. Furthermore, for enhancing the resilience against HJ attacks, the legitimate nodes exploit their own local observations of the wireless channel as the source of randomness to agree on shared secret... 

In this paper, a learning-aided content-based image transmission scheme is proposed, where a multi-antenna source wishes to securely deliver an image to a legitimate destination in the presence of randomly-distributed passive eavesdroppers (Eves). We take into account the fact that not all regions of an image have the same importance from the security perspective. Hence, we employ a hybrid method to realize both the error-free data delivery of public regions - containing less-important pixels; and an artificial noise (AN)-aided transmission scheme for securing the confidential packets. To reinforce system's security, fountain-based packet delivery is also adopted, where the source node... 

In this letter, we examine the PHY layer secret key generation (PHY-SKG) scheme in the presence of man-in-the-middle (MiM) adversary, while legitimate parties suffer from hardware impairments (HIs). Different from previous works on PHY-SKG that consider adversaries who simply try to make an interference in the communication link, the MiM aims to deceive legitimate entities about the source of common randomness. To conquer the MiM attack, legitimate parties utilize randomized pilots (RPs) in our proposed scheme. We analyze the effect of HIs on the performance of system by deriving the achievable secret key rate (SKR). Our results highlight a fundamental limit, as a ceiling phenomena, on the... 

Wireless secret key generation (WSKG) facilitates efficient key agreement protocols for securing the sixth generation (6G) wireless networks thanks to its inherently lightweight functionality. Nevertheless, with the existence of adversarial attacks or internal impairments, WSKG can be negatively affected during the randomness distillation, where the legitimate parties measure a source of common randomness. In this article, we propose a learning-aided approach for cooperative WSKG under man-in-the-middle (MitM) adversarial attack, while the legitimate nodes suffer from hardware impairments (HIs). The key idea is to process the PHY-attribute data on the application layer via deploying a deep...