Abstract

Enhanced security has often been cited as an important benefit of optical code-division multiple-access (O-CDMA) signaling but has seldom been analyzed in detail. This paper presents a theoretical analysis of the degree of confidentiality that can be provided by spectral-phase-encoded O-CDMA. Two eavesdropping detector structures are presented that can theoretically break the confidentiality of spectral-phase-encoded signals by detecting the code words in use by a specific user. One of them, an optical beat detector,is quantitatively analyzed to determine the probability of correctly detecting user code words. The confidentiality of user signals is shown to be vulnerable to such a detector if an eavesdropper can isolate a single user signal with a sufficiently high signal-to-noise ratio (SNR). At lower SNRs, combining multiple bits is shown to dramatically increase the probability of an eavesdropper correctly detecting user code words; even for codes long enough to strain implementation capabilities (e.g., 2048 code elements), the probability of correct detection is shown to rise from negligibly low values to virtually 100% by the combining of less than 100 transmitted bits at the eavesdropper's receiver.

© 2005 IEEE

PDF Article

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription