In this paper, we explore the physical layer security of an Internet of Things (IoT) network comprised of multiple relay-user pairs in the presence of multiple malicious eavesdroppers and channel estimation error (CEE). In order to guarantee secure transmission with channel estimation error, we propose a channel estimation error oriented joint relay-user pair and friendly jammer selection (CEE-JRUPaFJS) scheme to improve the physical layer security of IoT networks. For the purpose of comparison, the channel estimation error oriented traditional round-robin (CEE-TRR) scheme and the channel estimation error oriented traditional pure relay-user pair selection (CEE-TPRUPS) scheme are considered as benchmark schemes. The exact closed-form expressions of outage probability (OP) and intercept probability (IP) for the CEE-TRR and CEE-TPRUPS schemes as well as the CEE-JRUPaFJS scheme are derived over Rayleigh fading channels, which are employed to characterize network reliability and security, respectively. Moreover, the security-reliability tradeoff (SRT) is analyzed as a metric to evaluate the tradeoff performance of CEE-JRUPaFJS scheme. It is verified that the proposed CEE-JRUPaFJS scheme is superior to both the CEE-TRR and CEE-TPRUPS schemes in terms of SRT, which demonstrates our proposed CEE-JRUPaFJS scheme are capable of improving the security and reliability performance of IoT networks in the face of multiple eavesdroppers. Moreover, as the number of relay-user pairs increases, CEE-TPRUPS and CEE-JRUPaFJS schemes offer significant increases in SRT. Conversely, with an increasing number of eavesdroppers, the SRT of all these three schemes become worse.
In this paper, we explore the physical layer security of an Internet of Things (IoT) network comprised of multiple relay-user pairs in the presence of multiple malicious eavesdroppers and channel estimation error (CEE). In order to guarantee secure transmission with channel estimation error, we propose a channel estimation error oriented joint relay-user pair and friendly jammer selection (CEE-JRUPaFJS) scheme to improve the physical layer security of IoT networks. For the purpose of comparison, the channel estimation error oriented traditional round-robin (CEE-TRR) scheme and the channel estimation error oriented traditional pure relay-user pair selection (CEE-TPRUPS) scheme are considered as benchmark schemes. The exact closed-form expressions of outage probability (OP) and intercept probability (IP) for the CEE-TRR and CEE-TPRUPS schemes as well as the CEE-JRUPaFJS scheme are derived over Rayleigh fading channels, which are employed to characterize network reliability and security, respectively. Moreover, the security-reliability tradeoff (SRT) is analyzed as a metric to evaluate the tradeoff performance of CEE-JRUPaFJS scheme. It is verified that the proposed CEE-JRUPaFJS scheme is superior to both the CEE-TRR and CEE-TPRUPS schemes in terms of SRT, which demonstrates our proposed CEE-JRUPaFJS scheme are capable of improving the security and reliability performance of IoT networks in the face of multiple eavesdroppers. Moreover, as the number of relay-user pairs increases, CEE-TPRUPS and CEE-JRUPaFJS schemes offer significant increases in SRT. Conversely, with an increasing number of eavesdroppers, the SRT of all these three schemes become worse.
Abstract This paper examines a wireless communication network comprised of a source and multiple relay‐user pairs in face of multiple malicious eavesdroppers. In order to improve the physical layer security of cooperative communication networks, a joint relay‐user pair and friendly jammer selection (JRUPaFJS) scheme is proposed. Apart from the impacts of friendly jammers on the eavesdroppers, that on the legitimate users is also taken into account due to the presence of channel state information estimation errors. The traditional round‐robin (TRR) scheme and traditional pure relay‐user pair selection (TPRUPS) scheme are considered as benchmark schemes. The exact closed‐form expressions of outage probability and intercept probability for the TRR and TPRUPS schemes as well as JRUPaFJS scheme over Rayleigh fading channels are derived. It is verified that the proposed JRUPaFJS scheme outperforms both the TRR and TPRUPS schemes in terms of their SRT, which demonstrates the wireless security and reliability benefits of exploiting JRUPaFJS scheme. Moreover, as the number of relay‐user pairs increases, the SRT of the TPRUPS and JRUPaFJS schemes improve notably, while as the number of eavesdroppers increases, the SRT of all the three schemes become worse.
This paper investigates the physical-layer security (PLS) of wireless transmissions with the aid of multiple decode-and-forward one-way relays in the presence of both eavesdropping attacks and channel estimation errors (CEEs). To protect wireless transmission with CEE, two opportunistic relaying schemes are conceived to upgrade the PLS of the wireless communications with the aid of relays, namely, the CEE-oriented pure relay selection (CEE-PRS) and CEE-oriented jammer-aided relay selection (CEE-JRS), respectively. Moreover, the security-reliability tradeoff (SRT) is designed due to that increasing the transmit power may enhance the reliability, but the security may be sacrificed concurrently, where the security and reliability are characterized by the intercept probability (IP) and outage probability (OP), respectively. We then analyze the IP and OP of the CEE-PRS and CEE-JRS schemes. Furthermore, both the CEE-oriented direct transmission (CEE-DT) and the perfect channel estimation-oriented direct transmission (PCE-DT) schemes are also analyzed for comparison purposes. It is shown that although the SRT of the wireless communications can indeed be degraded by the eavesdropping attacks in low CEE regions, the proposed CEE-PRS and CEE-JRS schemes are capable of significant improving the SRT performance of wireless communications, demonstrating the advantage of the proposed CEE-PRS and CEE-JRS schemes against eavesdropping.
In this paper, we explore the physical-layer security in a wireless network consisting of multiple user pairs in the face of multiple eavesdroppers, which are deployed by an adversary for tapping the confidential transmissions of the user pairs deliberately. We propose a friendly jammer-assisted user-pair selection (FJaUPS) scheme to improve the security-reliability tradeoff (SRT). Conventionally, a friendly jammer is used to transmit the artificial noise that is specially designed onto the null space of the main channel (spanning from the source to legitimate destination) for the sake of not interfering with the destination. However, due to the presence of the channel state information estimation error, it is impossible to guarantee that the artificial noise perfectly lies in the null space of the main channel, resulting in a certain interference received at the legitimate destination caused by the friendly jammer. Hence, the impacts of the friendly jammer on the legitimate user transmissions and eavesdroppers are taken into account for evaluating the wireless SRT performance, which are quantified by the so-called self-interfering factor and jamming factor, respectively. Moreover, we derive the SRT of the proposed FJaUPS, as well as the traditional round-robin schemes over Rayleigh fading channels. For comparison purposes, we also provide the SRT result of the conventional pure user-pair selection (PUPS) in computer simulations. In addition, it is shown that the proposed FJaUPS schemes outperform both the traditional round-robin and PUPS methods in terms of their SRT.
In this paper, we investigate the physical-layer security for a wireless two-hop relay network in the presence of channel estimation errors when estimating the channel state information (CSI) of the main links (from the source via relays to the destination) and wiretap links (from the source and relays to the eavesdropper). The eavesdropper can not only overhear the confidential signals transmitted by the relays, but also tap the secret messages transmitted by the source. We present an channel estimation error oriented relay selection (CEEoRS) scheme to improve the security-reliability tradeoff (SRT). We also analyze the intercept probability and outage probability of the CEEoRS scheme, where the intercept probability and outage probability can quantify the security and reliability, respectively. For comparison purposes, the traditional direct transmission with channel estimation errors (TDTwCEE) is also analyzed. It is shown that the proposed CEEoRS scheme outperforms the TDTwCEE scheme in terms of its SRT. More specifically, the proposed CEEoRS scheme is capable of significantly improving the SRT performance of wireless communications through increasing the number of relays.
Internet of Things (IoT) plays a significant role in facilitating our work and making ease the life of human, for the reason that it can connect a lot of embedded devices to deal with many complicated and difficult tasks. However, security of IoT is more concern because every device is connected through internet network, and eavesdroppers are ready to steal or even uncover our private data. Therefore, in this paper, we propose joint single relay and jammer selection (JSRJS) to enhance the physical layer security (PLS) of IoT. Moreover, outage probability (OP) and intercept probability (IP) as well as the system tradeoff performance (STP) for JSRJS under Nakagami-m fading channel are analyzed, and OP, IP as well as STP of JSRJS are all compared with that of the pure single relay selection (SRS), respectively. Simulation results show that the OP of JSRJS is the same as that of SRS, while the IP of JSRJS is always better than that of SRS. In addition, the STP for JSRJS is also more perfect than that of SRS. Besides, as the number of relay nodes increases, the STP of these two approaches both improve notably.
In this paper, we investigate a novel joint multi-relay and jammer selection (JMRJS) scheme in order to improve the physical layer security of wireless networks. In the JMRJS scheme, all the relays succeeding in source decoding are selected to assist in the source signal transmission and meanwhile, all the remaining relay nodes are employed to act as friendly jammers to disturb the eavesdroppers by broadcasting artificial noise. Based on the more general Nakagami-m fading channel, we analyze the security performance of the JMRJS scheme for protecting the source signal against eavesdropping. The exact closed-form expressions of outage probability (OP) and intercept probability (IP) for the JMRJS scheme over Nakagami-m fading channel are derived. Moreover, we analyze the security-reliability tradeoff (SRT) of this scheme. Simulation results show that as the number of decode-and-forward (DF)relay nodes increases, the SRT of the JMRJS scheme improves notably. And when the transmit power is below a certain value, the SRT of the JMRJS scheme consistently outperforms the joint single-relay and jammer selection (JSRJS) scheme and joint equal-relay and jammer selection (JERJS) scheme respectively. In addition, the SRT of this scheme is always better than that of the multi-relay selection (MRS) scheme.