Physical layer security scheme for key concealment and distribution based on carrier scrambling

Area of Science:

• Information Security
• Optical Communications
• Chaos Theory

Background:

• Physical layer security is crucial for protecting communication networks against eavesdropping.
• Traditional security methods often rely on complex cryptographic algorithms.
• There is a need for efficient and integrated security solutions at the physical layer.

Purpose of the Study:

• To propose a novel physical layer security scheme for secure key concealment and distribution.
• To utilize chaotic sequences for encryption and key management.
• To demonstrate a scalable and flexible solution for secure optical communications.

Main Methods:

• Employing a three-dimensional (3D) Lorenz system to generate independent chaotic sequences for encryption.
• Loading key information into a specific subcarrier and scrambling it with ciphertext subcarriers.
• Integrating encrypted key position information with the training sequence (TS) for receiver demodulation.

Main Results:

• The proposed scheme successfully encrypts information at the bit, constellation, and subcarrier levels.
• Simultaneous scrambling of key and ciphertext subcarriers ensures secure key distribution.
• The training sequence accommodates up to 10 key position information, showing scalability.
• Safe transmission of 131.80 Gb/s Orthogonal Frequency Division Multiplexing (OFDM) signals over 2 km of 7-core fiber was achieved.

Conclusions:

• The developed scheme provides a promising solution for physical layer security in optical networks.
• It enables simultaneous flexible distribution and concealment of cryptographic keys.
• The method enhances network security by integrating encryption and key management at the physical layer.