Photonic-layer secure 56 Gb/s PAM4 optical communication based on common noise driven synchronous private temporal...

Area of Science:

• Optical Communications
• Network Security
• Cryptography

Background:

• Fiber-optic networks require robust security measures at the physical (photonic) layer to complement existing digital cryptography.
• Implementing effective photonic-layer security presents significant technical challenges, especially for high-speed data transmission.

Purpose of the Study:

• To propose and experimentally validate a novel, high-speed photonic-layer secure optical communication system.
• To enhance security in fiber-optic networks by supplementing upper-layer digital encryption methods.

Main Methods:

• Development of a common noise-driven synchronous private temporal phase en/decryption scheme.
• Experimental demonstration of the scheme supporting high-order modulation formats, specifically 4-level pulse amplitude modulation (PAM4).
• Transmission of encrypted signals over 20 km of optical fiber.

Main Results:

• Achieved a record bit rate of 56 Gb/s for a confidential PAM4 signal.
• Successfully encrypted and decrypted the signal using remotely synchronized private noise-like signals.
• Maintained a bit-error-rate (BER) below the hard-decision forward error correction (HD-FEC) limit.

Conclusions:

• The demonstrated common noise-driven synchronous private temporal phase en/decryption scheme offers a promising solution for ultrahigh-speed photonic-layer security.
• This approach enhances optical communication security by integrating physical-layer encryption capabilities.