Novel encryption technique for security enhancement in optical code division multiple access

In this paper, a novel two dimensional (2D) wavelength/time (W/T) optical code division multiple access (OCDMA) code with zero cross-correlation property to minimize multiple access interface (MAI) is addressed. The code is constructed using various features of two different one-dimensional codes, i.e., multi-diagonal code and prime hop code referred as multi-diagonal prime hopping (MDPHC) code. The proposed 2D W/T MDPHC code is generated using java software version 8.1, which is found to be optimal. In this paper, the code complexity of the proposed 2D code is also derived. In addition to the novel 2D code design, security provision at the photonic layer of the OCDMA network is also addressed by transmitting the data through a novel encrypted circuit in order to prevent attacks by an eavesdropper. In this work, the proposed encryption circuit is integrated with the proposed 2D (W/T) MDPHC OCDMA encoder to enhance the overall security performance. The proposed model is validated using optisystem software version 14. Robustness of the proposed technique against different types of attacks such as ciphertext-only attack, known plain text attack, chosen plaintext attack, energy detection attack in on off keying optical code division multiple access, Brute-force search attack is investigated theoretically. Bit error rate is also estimated for different fiber distances.