Security enhancement of quantum noise stream cipher system based on optical temporal scrambling

•The proposed optical temporal scrambling scheme can be excellent adaptability to improve the security of quantum noise stream cipher system (QNSC) system.•By using an cascade Fabry-Perot cavities architecture to implement the masking of time domain features.•This work provides a security enhancement method for QNSC system to implement the capability of anti-eavesdropping for optical fiber communication, which could be favorable for the deployment of optical network infrastructure.