Security weaknesses of underwater wireless optical communication

Area of Science:

• Optical Engineering
• Information Security
• Underwater Communications

Background:

• Underwater wireless optical communication (UWOC) is increasingly vital for data transmission in aquatic environments.
• Traditional security assumptions for UWOC may be insufficient due to the physics of light propagation in water.
• Potential vulnerabilities could compromise sensitive information transmitted through UWOC links.

Purpose of the Study:

• To investigate the security vulnerabilities of UWOC systems.
• To numerically and experimentally assess the risk of information leakage in UWOC.
• To validate the potential for eavesdropping on UWOC transmissions.

Main Methods:

• Monte Carlo simulations were employed to model security weaknesses.
• Experiments utilized a high-sensitivity multi-pixel photon counter (MPPC) to detect leaked signals.
• A 2.5-Gb/s orthogonal frequency division multiplexing (OFDM) signal was transmitted through a 15-m underwater channel for eavesdropping tests.

Main Results:

• Numerical simulations indicated increased information leakage probability with greater link distance and water turbidity.
• Experimental verification confirmed signal tapping at distances up to 5 meters using an MPPC.
• Successful eavesdropping of an OFDM signal was demonstrated at 7.8 meters, with both receivers achieving below the forward error correction (FEC) limit.

Conclusions:

• UWOC systems are susceptible to information leakage and eavesdropping.
• Environmental factors like distance and turbidity significantly impact UWOC security.
• The findings highlight a critical safety hazard for secure underwater data transmission.