Optical Engineering • Open AccessIsolated user security enhancement in optical code division multiple access network against eavesdropping
A novel virtual user system is modeled for enhancing the security of an optical code division multiple access (OCDMA) network. Although the OCDMA system implementing code shift keying (CSK) is secure against a conventional power detector, it is susceptible to differential eavesdropping. An analytical framework is developed for the CSK-OCDMA system to show eavesdropper's code interception performance for a single transmitting user in the presence of a virtual user. It is shown that the eavesdropper's probability of correct bit interception decreases from 7.1×10-1 to 1.85×10-5 with the inclusion of the virtual user. Furthermore, the results confirm that the proposed virtual user scheme increases the confidentiality of the CSK-OCDMA system and outperforms the conventional OCDMA scheme in terms of security.