With the rapid development of wireless networks, the application of wireless devices in the field of communication is be-coming increasingly widespread. However, the openness of wire-less channels makes them susceptible to various factors such as channel interference, leading to increased network security risks. This paper investigates a physical layer key generation scheme based on wireless channels and designs a complete system for key generation in one-to-many scenarios. The system includes four stages of the key generation scheme: channel measurement, quan-tization, key agreement, and privacy amplification. In the channel measurement stage, a sequence-based method is used to ensure signal reciprocity. Additionally, in the privacy amplification stage, a rule for key selection and combination is designed to make the key practically applicable. Finally, the performance and security of the system are experimentally tested and analyzed.
With the rapid development of wireless networks, the application of wireless devices in the field of communication is be-coming increasingly widespread. However, the openness of wire-less channels makes them susceptible to various factors such as channel interference, leading to increased network security risks. This paper investigates a physical layer key generation scheme based on wireless channels and designs a complete system for key generation in one-to-many scenarios. The system includes four stages of the key generation scheme: channel measurement, quan-tization, key agreement, and privacy amplification. In the channel measurement stage, a sequence-based method is used to ensure signal reciprocity. Additionally, in the privacy amplification stage, a rule for key selection and combination is designed to make the key practically applicable. Finally, the performance and security of the system are experimentally tested and analyzed.
Device-to-device communication is increasingly important for emerging wireless applications, including the Internet of Things and industry mobile networks. To establish a secure communication channel between multiple legitimate devices, key agreement is an essential first step. Physical layer channel information is a promising technology for achieving communication security by generating a shared channel key. In this paper, we propose an efficient and random method for generating channel keys based on channel state information (CSI). Firstly, we preprocess the available subcarriers to reduce the correlation of adjacent subcarriers. Secondly, we propose a novel quantization process to generate random and secure channel keys. The part consists of two phases: the quantization phase and the inconsistency removal phase. In the quantization stage, CSI sub carriers are grouped into small blocks, and appropriate thresholds are generated. Then, wireless users quantize the CSI subcarriers into initial bit streams of 0 and 1 with different thresholds. In the inconsistency removal phase, we design an error correction mechanism where wireless users exchange the discarded index sequences in the initial bit streams to achieve key sequence consistency. We implement the proposed scheme using off-the-shelf wireless devices and evaluate its performance. The experimental results show that each CSI packet can produce 30 bits, which have passed the NIST randomness tests.
Modern networking technologies involve the interconnection of smart and intelligent physical objects to provide advanced services. These physical objects may be part of various network technologies like WLAN, wireless sensor network (WSN), Internet of Things (IoT), etc., and share data in wireless mode, which should be secured from threats. These physical devices possess many constraints like power, computational complexity and storage, and are required to have lightweight security algorithms. Traditionally, security is achieved by the higher layers of the communication model, which has high computational complexity and consumes more power. In this chapter, a secure-key-generation scheme from physical layer characteristics is introduced as a possible lightweight security alternative to traditional upper-layer security approaches. The proposed scheme is based on the wiretap-channel model and security is achieved by generating keys at both communicating ends independently, based on inherent common-channel characteristics like randomness. It is mainly based on the principle of spatial decorrelation and channel reciprocity for identical carrier frequency. There is no provision for sharing keys as in public-key cryptography, so physical-layer key generation is not vulnerable to threats like key leakage. The generated key at the transmitter encrypts plain text; the generated cipher is transmitted on the common channel and is decrypted at the receiver end using the key generated by the receiver. Key generation consists of fundamental blocks like channel probing and quantization followed by information reconciliation and privacy amplification. The physical-layer key generation is already a power-efficient security solution; this chapter aims to enhance this capacity further. This is done by introducing low-end signal conditioning in the channel-probing step using moving-window averaging. This solution not only improves system performance but also makes it suitable for limited- power applications. The performance of the key-generation system is characterised in terms of the bit-disagreement rate between the generated key sequences of communicating parties and the key randomness by means of the NIST statistical test suite.
Wireless communication systems are becoming increasingly important in our daily lives, especially with the rapid expansion of the Internet of Things (IoT). Secure and reliable communication is essential for the correct functioning of critical applications and use cases such as healthcare, finance, transportation, and industrial automation. However, the growing number of connected devices introduces significant challenges to data security and privacy due to the open nature of wireless networks. While traditional encryption methods are effective, they can be resource-intensive and impractical for resource-constrained IoT environments. Physical layer security (PLS) provides a lightweight alternative by leveraging the inherent characteristics of wireless channels to generate symmetric secret keys without requiring third-party infrastructure. The PLS key generation process involves four main stages: channel sampling, quantization, reconciliation, and privacy amplification. This paper provides a comprehensive survey of existing quantization schemes, as this step plays a crucial role in determining the key generation rate (KGR) and key disagreement rate (KDR). Additionally, the paper classifies quantization methods as either lossless or lossy, providing insights into the trade-offs between security and efficiency.
The new power system is the national development strategy and development direction of smart grid. Communication is the basis of the development of the new power system. in the distribution automation business, communication is the weakest link. In order to make electric power communication develop more smoothly, we should improve our awareness of security issues. Because of the particularity of electric power communication, it often has very high requirements for the security of communication. In order to effectively ensure the security of electric power communication data, data encryption technology can be applied to the data transmission process, and the security of information transmission can be improved through the application of encryption and decryption keys.Physical layer key generation technology is a security technology that uses wireless channel characteristics as a random source to generate keys. This technology uses the anisotropy, time variation and spatial uniqueness of wireless channels to generate random sequences, which is different from traditional encryption methods. Physical layer key generation technology does not require the key management and distribution of a third party trusted organization. In theory, it can achieve one encryption at a time to achieve the absolute security of Shannon confidential communication[1]. This paper first briefly introduces the wireless channel physical layer key generation model and the general process of key generation scheme based on channel feature quantization, and then studies the improved optimization scheme based on traditional channel detection, preprocessing and quantization algorithm, so as to effectively improve the key generation performance.
This paper introduces a novel physical layer secure communication technology based on wireless channel direct encryption to enhance the encryption strength of the information source. Unlike traditional methods of key generation based on the reciprocity of the wireless channel, which typically involve quantizing the wireless channel and then negotiating keys, resulting in two completely identical bit strings generated as encryption keys for upper-level cryptographic algorithms between legitimate communication parties, this paper's approach quantizes the quantized bits of the wireless channel characteristics of both legitimate parties and directly encrypts the information source bits by using a designed lightweight encryption/decryption algorithm. Compared to traditional approaches, this paper's method avoids the key consultation process for physical layer key distribution, expanding the scenarios for the use of physical layer keys. Moreover, it can work independently at the same time with the upper layer cryptography to enhance the encryption strength. Through experimental verification, it has been confirmed that, in cases where the channel error rate during information transmission is less than 5*10^-2, this model can achieve an average reception accuracy of 99.6% for legitimate communicators while ensuring that eavesdroppers cannot decrypt. This approach can also compatible with upper-layer security encryption/decryption algorithms at each layer of the OSI, e.g., data link layer and network layer, offering extensive application prospects.
In recent years, physical layer security has become one of the core technologies for wireless communication system security. Physical layer encryption is based on the inherent reciprocity, time-varying, spatial uniqueness and unpredictability of wireless communication systems to generate keys, which are naturally unforgeable and steganography-proof. However, the research of physical layer key generation technology also faces many challenges, such as the problem of poor key generation performance due to signal interference, the problem of lower randomness and slower key generation rate in quasi-static channel environment, and the problem of lower key consistency between two legitimate communication parties due to the existence of channel estimation errors; this paper provides a systematic explanation of the traditional model of key generation for wireless channels and a typical solution for this series of problems. In this paper, the traditional model of wireless channel key generation is systematically explained, and the typical solutions to this series of problems are studied, analysed and compared in terms of performance.