Experimental Study on Key Generation for Physical Layer Security in Wireless Communications

Abstract

This paper presents a thorough experimental study on key generation principles, i.e., temporal variation, channel reciprocity, and spatial decorrelation, through a testbed constructed by using wireless open-access research platform. It is the first comprehensive study through: 1) carrying out a number of experiments in different multipath environments, including an anechoic chamber, a reverberation chamber, and an indoor office environment, which represents little, rich, and moderate multipath, respectively; 2) considering static, object moving, and mobile scenarios in these environments, which represents different levels of channel dynamicity; and 3) studying two most popular channel parameters, i.e., channel state information and received signal strength. Through results collected from over a hundred tests, this paper offers insights to the design of a secure and efficient key generation system. We show that multipath is essential and beneficial to key generation as it increases the channel randomness. We also find that the movement of users/objects can help introduce temporal variation/randomness and help users reach an agreement on the keys. This paper complements existing research by experiments constructed by a new hardware platform.INDEX TERMS Physical layer security, key generation, wireless communications.

On the Key Generation From Correlated Wireless Channels

“…This requirement is relatively easy to meet. It has been reported in [9] that a key generation system with τ = 60 × 10 −6 s is designed. The mutual information change versus Doppler spread, f d , is shown in Fig.…”

“…By taking into account the effects of channel qualities and channel estimation, a more practical implementation and setup was considered in [6]. Spatial decorrelation was experimentally studied in [7]- [9].…”

Performance improvement of wireless secret key generation with colored noise for IoT

“…An elementary model for a wireless key generation was built, and various modifications in each block to enhance the performance of the overall system were proposed by Saad et al 11 Xu et al 12 proposed a low complexity group secret key generation approach by combining basic techniques like one time pad for various types of communication network. 13 Junqing et al 14 present guidelines related to practical design issue for secure key generation by considering parameters like sampling delay, pilot length, Doppler spread, etc. Further experimental study of the key generation approach in various real-time environments was done, and sufficient key agreement is achieved.…”

“…Further experimental study of the key generation approach in various real-time environments was done, and sufficient key agreement is achieved. 13 Junqing et al 14 present guidelines related to practical design issue for secure key generation by considering parameters like sampling delay, pilot length, Doppler spread, etc. The authors consider Nakagami-m fading channel with Gaussian noise and demonstrated a level crossing rate (LCR)-based key generation protocol by considering Doppler shift, fading, and number of paths with two level quantizers.…”

Securing Wireless Communications of the Internet of Things from the Physical Layer, An Overview

“…When the system works at 2.4 GHz, a half-wavelength is about 6 cm, which is quite short. These principles have been theoretically modeled and analyzed in [43], [44] and experimentally validated in [38], [39].…”