Core Concepts
Ensuring secure communication is crucial for mission-critical applications supported by Ultra-Reliable Low-Latency Communication (URLLC) in 5G and future 6G networks. This survey presents a comprehensive review of the state-of-the-art physical layer security (PLS) techniques used to provide secure URLLC while analyzing the impact of various system design parameters on its performance.
Abstract
This survey provides a detailed overview of the recent advancements in PLS techniques for securing URLLC service in 5G and future 6G wireless networks. It starts by discussing the fundamentals of URLLC, including the impact of finite blocklength on its security, and the various security threats like jamming, eavesdropping, and pilot contamination attacks.
The survey then presents an in-depth analysis of the key PLS performance evaluation metrics specifically designed for finite blocklength URLLC, such as secrecy rate, secrecy throughput, secrecy outage probability, and secrecy gap. It discusses how these metrics capture the trade-off between the reliability, latency, and security constraints of URLLC.
Next, the survey covers the recent developments in PLS techniques used for various URLLC enabling technologies, including NOMA, MIMO, cooperative communication using UAVs, and intelligent reflective surfaces (IRS). It also discusses the role of advanced machine learning techniques in designing robust and intelligent PLS schemes for URLLC.
Furthermore, the survey introduces the extended service class of URLLC in 6G, i.e., Hyper Reliable Low Latency Communication (HRLLC), and provides an outlook on the future security aspects. It identifies promising new technologies like quantum communication and blockchain that can provide secure HRLLC in 6G.
Finally, the survey highlights the key challenges and open issues faced by URLLC in achieving the desired security levels from the physical layer perspective and suggests several future research directions to address them.
Stats
The achievable secure data rate of user u in the finite blocklength regime is affected by back-off factors like the decoding error probability at the legitimate receiver and the information leakage probability of the eavesdropper.
The channel dispersion parameter at high SNR can be approximated to 1, but for low SNR conditions, this approximation does not hold well.
Accurate CSI estimation is essential for PLS, but it is challenging due to the dynamic wireless environment and delay in getting feedback for URLLC.
Pilot-assisted communication is adopted for CSI estimation, but the pilot signal length needs to be optimized to address the low latency constraint of URLLC.
Quotes
"The achievable secure data rate of user u in the finite blocklength regime is affected by back-off factors like the decoding error probability at the legitimate receiver and the information leakage probability of the eavesdropper."
"Accurate CSI estimation is essential for PLS, but it is challenging due to the dynamic wireless environment and delay in getting feedback for URLLC."
"Pilot-assisted communication is adopted for CSI estimation, but the pilot signal length needs to be optimized to address the low latency constraint of URLLC."