Bernard Wu

A method for secure communications over a public fiber-optical network

We develop a spread-spectrum based approach to secure communications over existing public fiber-optical networks. The secure channel is hidden under the noise floor of the network thus allowing cryptographic and steganographic security capabilities.

Secure transmission over an existing public WDM lightwave network

We develop a spread-spectrum-based approach to security-enhanced transmission over an existing public wavelength-division-multiplexing (WDM) lightwave network. Secure transmission for a dedicated user is achieved by overlaying a covert channel onto a multichannel WDM network. The covert channel is spectrally encoded using the technique of frequency hopping and then temporally spread by a dispersive element, with the resulting average power below the noise floor in the fiber. The presence of the WDM channels provides an ad hoc security expansion and increases the difficulty for an eavesdropper to intercept and decode the secure signal

Stealth Transmission over a WDM Network with Detection Based on an All-Optical Thresholder

An experimental demonstration of stealth transmission over a public WDM network is presented. An all-optical thresholder is utilized to minimize the power in the stealth channel, enabling efficient channel hiding in both time and spectral domains.

Steganographic fiber-optic transmission using coherent spectral-phase-encoded optical CDMA

Stealth communication using coherent SPE-OCDMA is demonstrated. The coherent approach can provide higher spectral efficiency than incoherent optical CDMA.

Advanced coding techniques for asynchronous fiber-optical CDMA

We develop new coding methods for asynchronous optical CDMA systems with increased spectral efficiency and better BER performance. Furthermore, our approach allows random variations of the transmission rate, thus improving the physical level security.

Experimental Evaluation of Near-Far Effect in Optically-Thresholded OCDMA Network Transporting Gigabit Ethernet Traffic

The near-far effect in a two-user OCDMA network carrying GbE traffic and employing all-optical thresholding is experimentally evaluated. A packet loss of <1.6% is observed with interfering to desired channel power ratio of 1 dB.

Security Analysis of Stealth Transmission over a public Fiber-Optical Network

We analyze the security performance of stealth communications over a public fiber-optical network. We examine systems vulnerability against various eavesdropping strategies and construct a metric to evaluate the level of security in the stealth transmission.

Achieving Physical Layer Security / Privacy with Self-Wrapped OCDM Transmission

We present a novel transmission system using self-wrapped WHTS OCDM signals to achieve enhanced transmission security. Distributed key is encoded and time-spread to hide under noise in the network. BER of 10-4 is demonstrated experimentally.

Secure communications over a public fiber-optical network

We develop a spread-spectrum based approach to secure communications over existing public fiber-optical networks. The secure channel is hidden under the noise floor of the network thus allowing cryptographic and steganographic security capabilities.

Secure stealth transmission over an existing public fiber-optical network

We develop a spread-spectrum based approach to secure communications over existing public fiber-optical networks. The secure channel is hidden under the noise floor of the network thus allowing cryptographic and steganographic security capabilities.